API – My Projects & Live

Golang and Gin Restful API

Ref: https://santrikoding.com/tutorial-restful-api-golang-1-membuat-project-golang

Note: Make sure golang is already installed by checking with ‘go version’ on your linux terminal
[codesyntax lang=”bash”]

satria@teddy:~$ go version
go version go1.18.3 linux/amd64

1 2	satria@teddy:~$ go version go version go1.18.3 linux/amd64

[/codesyntax]
Note: it’ll be better to use the newest go version. I already installed go version 1.23.4
[codesyntax lang=”bash”]

satria@teddy:~/Downloads$ go version
go version go1.23.4 linux/amd64

1 2	satria@teddy:~/Downloads$ go version go version go1.23.4 linux/amd64

[/codesyntax]

Note: don’t forget to run ‘go mod tidy’ on your go project

1. Create a new directory for this project named ‘go-restful-api’ then go into the directory
[codesyntax lang=”bash”]

satria@teddy:~/Documents/projects$ mkdir go-restful-api
satria@teddy:~/Documents/projects$ cd go-restful-api/

1 2	satria@teddy:~/Documents/projects$ mkdir go-restful-api satria@teddy:~/Documents/projects$ cd go-restful-api/

[/codesyntax]

then type this to create a new module ‘advcha/backend-api’
[codesyntax lang=”bash”]

satria@teddy:~/Documents/projects/go-restful-api$ go mod init advcha/backend-api
go: creating new go.mod: module advcha/backend-api

1 2	satria@teddy:~/Documents/projects/go-restful-api$ go mod init advcha/backend-api go: creating new go.mod: module advcha/backend-api

[/codesyntax]

2. Install ‘Gin’ and the libraries. Gin is a go-based web framework
[codesyntax lang=”bash”]

satria@teddy:~/Documents/projects/go-restful-api$ go get -u github.com/gin-gonic/gin
go: downloading github.com/gin-gonic/gin v1.10.0
...
github.com/gin-gonic/gin imports
	github.com/gin-gonic/gin/binding imports
	github.com/pelletier/go-toml/v2 imports
	slices: package slices is not in GOROOT (/usr/local/go/src/slices)

satria@teddy:~/Documents/projects/go-restful-api$ go get -u github.com/gin-gonic/gin

go: downloading github.com/gin-gonic/gin v1.10.0

...

github.com/gin-gonic/gin imports

github.com/gin-gonic/gin/binding imports

github.com/pelletier/go-toml/v2 imports

slices: package slices is not in GOROOT (/usr/local/go/src/slices)

[/codesyntax]

3. Create a ‘Hello World’ with Gin
create a new file ‘main.go’ then here is the content
[codesyntax lang=”text”]

package main

import (
	"github.com/gin-gonic/gin"
)

func main() {
	// initialize Gin
	router := gin.Default()

	// create a GET route with an endpoint "/"
	router.GET("/", func(c *gin.Context) {
		// return JSON response
		c.JSON(200, gin.H{
			"message": "Hello World!",
		})
	})

	// start the server with port 3000
	router.Run(":3000") // listen and serve on
}

package main

import (

"github.com/gin-gonic/gin"

)

func main() {

// initialize Gin

router := gin.Default()

// create a GET route with an endpoint "/"

router.GET("/", func(c *gin.Context) {

// return JSON response

c.JSON(200, gin.H{

"message": "Hello World!",

})

// start the server with port 3000

router.Run(":3000") // listen and serve on

}

[/codesyntax]

4. Run it with ‘go run main.go’
[codesyntax lang=”bash”]

satria@teddy:~/Documents/projects/go-restful-api$ go run main.go
[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.

[GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.
 - using env:	export GIN_MODE=release
 - using code:	gin.SetMode(gin.ReleaseMode)

[GIN-debug] GET    /                         --&gt; main.main.func1 (3 handlers)
[GIN-debug] [WARNING] You trusted all proxies, this is NOT safe. We recommend you to set a value.
Please check https://pkg.go.dev/github.com/gin-gonic/gin#readme-don-t-trust-all-proxies for details.
[GIN-debug] Listening and serving HTTP on :3000

satria@teddy:~/Documents/projects/go-restful-api$ go run main.go

[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.

[GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.

- using env: export GIN_MODE=release

- using code: gin.SetMode(gin.ReleaseMode)

[GIN-debug] GET / --> main.main.func1 (3 handlers)

[GIN-debug] [WARNING] You trusted all proxies, this is NOT safe. We recommend you to set a value.

Please check https://pkg.go.dev/github.com/gin-gonic/gin#readme-don-t-trust-all-proxies for details.

[GIN-debug] Listening and serving HTTP on :3000

[/codesyntax]

5. open it on your browser with http://localhost:3000/
it should print

{"message":"Hello World!"}

1	{"message":"Hello World!"}

Install GORM (Go ORM). it’s a Object Relational Mapping (ORM) for Golang
1. Install GORM with MySQL driver
[codesyntax lang=”bash”]

satria@teddy:~/Documents/projects/go-restful-api$ go get -u gorm.io/gorm gorm.io/driver/mysql
go: downloading gorm.io/gorm v1.25.12
go: downloading gorm.io/driver/mysql v1.5.7
go: downloading github.com/go-sql-driver/mysql v1.7.0
go: downloading github.com/jinzhu/now v1.1.5
go: downloading github.com/jinzhu/inflection v1.0.0
go: downloading github.com/go-sql-driver/mysql v1.8.1
go: downloading filippo.io/edwards25519 v1.1.0
go: added filippo.io/edwards25519 v1.1.0
go: added github.com/go-sql-driver/mysql v1.8.1
go: added github.com/jinzhu/inflection v1.0.0
go: added github.com/jinzhu/now v1.1.5
go: upgraded golang.org/x/text v0.15.0 =&gt; v0.21.0
go: added gorm.io/driver/mysql v1.5.7
go: added gorm.io/gorm v1.25.12

satria@teddy:~/Documents/projects/go-restful-api$ go get -u gorm.io/gorm gorm.io/driver/mysql

go: downloading gorm.io/gorm v1.25.12

go: downloading gorm.io/driver/mysql v1.5.7

go: downloading github.com/go-sql-driver/mysql v1.7.0

go: downloading github.com/jinzhu/now v1.1.5

go: downloading github.com/jinzhu/inflection v1.0.0

go: downloading github.com/go-sql-driver/mysql v1.8.1

go: downloading filippo.io/edwards25519 v1.1.0

go: added filippo.io/edwards25519 v1.1.0

go: added github.com/go-sql-driver/mysql v1.8.1

go: added github.com/jinzhu/inflection v1.0.0

go: added github.com/jinzhu/now v1.1.5

go: upgraded golang.org/x/text v0.15.0 => v0.21.0

go: added gorm.io/driver/mysql v1.5.7

go: added gorm.io/gorm v1.25.12

[/codesyntax]

2. Create a new .env file to store the variables like the database name, password, etc.
[codesyntax lang=”text”]

export DB_USERNAME=your_mysql_username
export DB_PASSWORD=your_mysql_password
export DB_HOST=127.0.0.1
export DB_PORT=3306
export DB_NAME=db_go_restful_api

export DB_USERNAME=your_mysql_username

export DB_PASSWORD=your_mysql_password

export DB_HOST=127.0.0.1

export DB_PORT=3306

export DB_NAME=db_go_restful_api

[/codesyntax]
Note: rename ‘your_mysql_username’ and ‘your_mysql_password’ for your mysql account
‘db_go_restful_api’ is the database name we will create later

We need to install a package ‘github.com/joho/godotenv’ on the terminal ‘go get github.com/joho/godotenv’ to read the .env file
Note: run ‘go mod tidy’ to install any missing packages if exist

2. Create a Post model
create a new directory ‘models’ then create a new file ‘post.go’ in it. here is the file content
[codesyntax lang=”text”]

package models

type Post struct {
	// ID is the unique identifier of the post
	ID 	int 	`json:"id" gorm:"primary_key"`
	// Title is the title of the post
	Title 	string 	`json:"title"`
	// Content is the content of the post
	Content string 	`json:"content"`
}

package models

type Post struct {

// ID is the unique identifier of the post

ID int `json:"id" gorm:"primary_key"`

// Title is the title of the post

Title string `json:"title"`

// Content is the content of the post

Content string `json:"content"`

}

[/codesyntax]

3. create a database connection
create a new file ‘setup.go’ in the ‘models’ directory. here is the file content
[codesyntax lang=”text”]

package models

import (
	"fmt"
	"os"
	"gorm.io/driver/mysql"
	"gorm.io/gorm"
)

var DB *gorm.DB

func ConnectDatabase() {
	// create a database connection. The connection string is in the format:
	username := os.Getenv("DB_USERNAME")
	password := os.Getenv("DB_PASSWORD")
	host := os.Getenv("DB_HOST")
	port := os.Getenv("DB_PORT")
	dbname := os.Getenv("DB_NAME")

	dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?charset=utf8mb4&amp;parseTime=True&amp;loc=Local",
		username, password, host, port, dbname)
	
	database, err := gorm.Open(mysql.Open(dsn), &amp;gorm.Config{})

	// check if there is an error when connecting to the database
	if err != nil {
		panic("Failed to connect to database!")
	}

	// if there is no error, then create a table for the 'Post' model
	database.AutoMigrate(&amp;Post{})

	// assign the database connection to the global variable 'DB'
	DB = database
}

func GetDB() *gorm.DB {
	return DB
}

package models

import (

"fmt"

"os"

"gorm.io/driver/mysql"

"gorm.io/gorm"

)

var DB *gorm.DB

func ConnectDatabase() {

// create a database connection. The connection string is in the format:

username := os.Getenv("DB_USERNAME")

password := os.Getenv("DB_PASSWORD")

host := os.Getenv("DB_HOST")

port := os.Getenv("DB_PORT")

dbname := os.Getenv("DB_NAME")

dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?charset=utf8mb4&parseTime=True&loc=Local",

username, password, host, port, dbname)

database, err := gorm.Open(mysql.Open(dsn), &gorm.Config{})

// check if there is an error when connecting to the database

if err != nil {

panic("Failed to connect to database!")

}

// if there is no error, then create a table for the 'Post' model

database.AutoMigrate(&Post{})

// assign the database connection to the global variable 'DB'

DB = database

}

func GetDB() *gorm.DB {

return DB

}

[/codesyntax]

4. create a new mysql database ‘db_go_restful_api’

5. Create a new Post controller ‘postController.go’ in ‘controllers’ directory
[codesyntax lang=”text”]

package controllers

import (
	"advcha/backend-api/models"
	"github.com/gin-gonic/gin"
)

// get all posts
func FindPosts(c *gin.Context) {
	// get all posts from the database
	var posts []models.Post
	models.DB.Find(&amp;posts)

	// return JSON response
	c.JSON(200, gin.H{
		"status": "success",
		"message": "All posts retrieved successfully",
		"data": posts
	})
}

package controllers

import (

"advcha/backend-api/models"

"github.com/gin-gonic/gin"

)

// get all posts

func FindPosts(c *gin.Context) {

// get all posts from the database

var posts []models.Post

models.DB.Find(&posts)

// return JSON response

c.JSON(200, gin.H{

"status": "success",

"message": "All posts retrieved successfully",

"data": posts

})

}

[/codesyntax]

6. Create a route API Post
edit main.go to import the models and controllers. Also put the route in it. so it’ll be like this
[codesyntax lang=”text”]

package main

import (
	"advcha/backend-api/controllers"
	"advcha/backend-api/models"
	"github.com/joho/godotenv"
	"github.com/gin-gonic/gin"
	"log"
)

func main() {
	// load the .env file
	err := godotenv.Load()
	if err != nil {
		log.Fatal("Error loading .env file")
	}

	// initialize Gin
	router := gin.Default()

	// connect to the database
	models.ConnectDatabase()

	// create a GET route with an endpoint "/"
	router.GET("/", func(c *gin.Context) {
		// return JSON response
		c.JSON(200, gin.H{
			"message": "Hello World!",
		})
	})

	// create a GET route with an endpoint "/posts"
	router.GET("/api/posts", controllers.FindPosts)

	// start the server with port 3000
	router.Run(":3000") // listen and serve on
}

package main

import (

"advcha/backend-api/controllers"

"advcha/backend-api/models"

"github.com/joho/godotenv"

"github.com/gin-gonic/gin"

"log"

)

func main() {

// load the .env file

err := godotenv.Load()

if err != nil {

log.Fatal("Error loading .env file")

}

// initialize Gin

router := gin.Default()

// connect to the database

models.ConnectDatabase()

// create a GET route with an endpoint "/"

router.GET("/", func(c *gin.Context) {

// return JSON response

c.JSON(200, gin.H{

"message": "Hello World!",

})

// create a GET route with an endpoint "/posts"

router.GET("/api/posts", controllers.FindPosts)

// start the server with port 3000

router.Run(":3000") // listen and serve on

}

[/codesyntax]

7. Run it and open it on your browser
If everything okay, the url http://localhost:3000/api/posts will show

{"data":[],"message":"All posts retrieved successfully","status":"success"}

1	{"data":[],"message":"All posts retrieved successfully","status":"success"}

Note: Also we can check it via Postman
create a new collection ‘Go Gin Restful API’ then create a new GET request ‘api_posts’ with url http://localhost:3000/api/posts

Insert data into the database
1. Create a new function ‘InsertPost’ in postController.go
note: first, we need to install a package ‘github.com/go-playground/validator/v10′[codesyntax lang=”bash”]

satria@teddy:~/Documents/projects/go-restful-api$ go get github.com/go-playground/validator/v10
go: upgraded github.com/gabriel-vasile/mimetype v1.4.3 =&gt; v1.4.8
go: upgraded github.com/go-playground/validator/v10 v10.20.0 =&gt; v10.24.0
go: upgraded golang.org/x/crypto v0.23.0 =&gt; v0.32.0
go: upgraded golang.org/x/net v0.25.0 =&gt; v0.34.0
go: upgraded golang.org/x/sys v0.20.0 =&gt; v0.29.0
satria@teddy:~/Documents/projects/go-restful-api$ go mod tidy

satria@teddy:~/Documents/projects/go-restful-api$ go get github.com/go-playground/validator/v10

go: upgraded github.com/gabriel-vasile/mimetype v1.4.3 => v1.4.8

go: upgraded github.com/go-playground/validator/v10 v10.20.0 => v10.24.0

go: upgraded golang.org/x/crypto v0.23.0 => v0.32.0

go: upgraded golang.org/x/net v0.25.0 => v0.34.0

go: upgraded golang.org/x/sys v0.20.0 => v0.29.0

satria@teddy:~/Documents/projects/go-restful-api$ go mod tidy

[/codesyntax]

[codesyntax lang=”text”]

package controllers

import (
	"errors"
	"net/http"
	"advcha/backend-api/models"
	"github.com/gin-gonic/gin"
	"github.com/go-playground/validator/v10"
)

// ValidatePostInput struct is used to validate the input of the post
type ValidatePostInput struct {
	Title string `json:"title" binding:"required"`
	Content string `json:"content" binding:"required"`
}

// ErrorMsg struct is used to return the error message
type ErrorMsg struct {
	Field   string `json:"field"`
	Message string `json:"message"`
}

// GetErrorMsg function is used to get the error message
func GetErrorMsg(fe validator.FieldError) string {
	switch fe.Tag() {
	case "required":
		return "This field is required"
	}
	return "Unknown error"
}

// get all posts
func FindPosts(c *gin.Context) {
	// get all posts from the database
	var posts []models.Post
	models.DB.Find(&amp;posts)

	// return JSON response
	c.JSON(200, gin.H{
		"status": "success",
		"message": "All posts retrieved successfully",
		"data": posts,
	})
}

func InsertPost(c *gin.Context) {
	// validate the input
	var input ValidatePostInput

	if err := c.ShouldBindJSON(&amp;input); err != nil {
		var ve validator.ValidationErrors
		if errors.As(err, &amp;ve) {
			out := make([]ErrorMsg, len(ve))
			for i, fe := range ve {
				out[i] = ErrorMsg{fe.Field(), GetErrorMsg(fe)}
			}
			c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": out})
		}
		return
	}

	// create a new post
	post := models.Post{Title: input.Title, Content: input.Content}

	// insert the new post into the database
	models.DB.Create(&amp;post)

	// return JSON response
	c.JSON(200, gin.H{
		"status": "success",
		"message": "Post created successfully",
		"data": post,
	})
}

package controllers

import (

"errors"

"net/http"

"advcha/backend-api/models"

"github.com/gin-gonic/gin"

"github.com/go-playground/validator/v10"

)

// ValidatePostInput struct is used to validate the input of the post

type ValidatePostInput struct {

Title string `json:"title" binding:"required"`

Content string `json:"content" binding:"required"`

}

// ErrorMsg struct is used to return the error message

type ErrorMsg struct {

Field string `json:"field"`

Message string `json:"message"`

}

// GetErrorMsg function is used to get the error message

func GetErrorMsg(fe validator.FieldError) string {

switch fe.Tag() {

case "required":

return "This field is required"

}

return "Unknown error"

}

// get all posts

func FindPosts(c *gin.Context) {

// get all posts from the database

var posts []models.Post

models.DB.Find(&posts)

// return JSON response

c.JSON(200, gin.H{

"status": "success",

"message": "All posts retrieved successfully",

"data": posts,

})

}

func InsertPost(c *gin.Context) {

// validate the input

var input ValidatePostInput

if err := c.ShouldBindJSON(&input); err != nil {

var ve validator.ValidationErrors

if errors.As(err, &ve) {

out := make([]ErrorMsg, len(ve))

for i, fe := range ve {

out[i] = ErrorMsg{fe.Field(), GetErrorMsg(fe)}

}

c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": out})

}

return

}

// create a new post

post := models.Post{Title: input.Title, Content: input.Content}

// insert the new post into the database

models.DB.Create(&post)

// return JSON response

c.JSON(200, gin.H{

"status": "success",

"message": "Post created successfully",

"data": post,

})

}

[/codesyntax]

2. Then add a route in main.go to insert the post like this
[codesyntax lang=”text”]

func main() {
	...

	// create a GET route with an endpoint "/posts"
	router.GET("/api/posts", controllers.FindPosts)

	// create a POST route with an endpoint "/posts"
	router.POST("/api/posts", controllers.InsertPost)

	// start the server with port 3000
	router.Run(":3000") // listen and serve on
}

func main() {

...

// create a GET route with an endpoint "/posts"

router.GET("/api/posts", controllers.FindPosts)

// create a POST route with an endpoint "/posts"

router.POST("/api/posts", controllers.InsertPost)

// start the server with port 3000

router.Run(":3000") // listen and serve on

}

[/codesyntax]

3. Run and test with Postman

Note: also need to test the validation with a json for empty title and content to make sure the validation is working.
the above screen showed the json with title and content and the success result
the output on http://localhost:3000/api/posts will be like this:

{"data":[{"id":1,"title":"My First Post","content":"Here is the content of my first post"}],"message":"All posts retrieved successfully","status":"success"}

1	{"data":[{"id":1,"title":"My First Post","content":"Here is the content of my first post"}],"message":"All posts retrieved successfully","status":"success"}

REST API OAuth PHP Client Best Practice and Dissection

WooCommerce REST API PHP Client Library
“A PHP wrapper for the WooCommerce REST API. Easily interact with the WooCommerce REST API using this library.”
PHP Client: https://github.com/kloon/WooCommerce-REST-API-Client-Library
It still supports the OAuth 1 one-legged (use consumer key and secret for the authentication), limited OOP, no test
Tutorial: https://www.skyverge.com/blog/using-woocommerce-rest-api-introduction/
https://www.skyverge.com/blog/using-woocommerce-rest-api-orders-endpoint/ (complete with curl and Http implementations and samples result)
Great tutorial to use/extend woocommerce: https://www.skyverge.com/blog/category/tutorials/woocommerce-tutorials/.

Salesforce REST API

Ref: Step One: Obtain a Salesforce Developer Edition Organization

Go to https://developer.salesforce.com/signup to register.SORRY, ONLY ADMIN CAN SHOW THIS!
Check your email if you got an email confirmation from salesforce has been arrived (‘Welcome to Force.com Developer Edition’). then click the link in the email to set/change your salesforce pasword
Done! Click ‘Setup’ and find ‘Add App’ to create a salesforce App.Click ‘Add App’
Fill the App entriesThen click ‘Create’
Here is my app (STILL DON’T HOW TO USE IT!!!!)Click ‘Go To My App’
Here is the app looks
Url: https://ap4.salesforce.com/a00/o?tsid=02u6F000000v1oN

Elance API on WordPress Without WP Plugin

Elance has gone now and merged with Odesk to establish a new company Upwork. Once I successfully used Elance API on my wordpress website without using wordpress plugin. I know it’s a bad practice but it’s work anyway. Here is how to do it:

Make sure you already registered on elance (https://elance.com) and have any elance key. If not go to https://developers.elance.com and get the keys (API Key, API secret, redirect URL, etc). Here is the keys:
SORRY, ONLY ADMIN CAN SHOW THIS!

I created a new wordpress template page with name ‘My Elance Jobs’ in a new file ‘my_elance_page.php’ in the active wordpress theme (currently the active theme is Sorbet). Based on some PHP example to use Elance API, Here is the complete content:

<?php
/*
Template Name: My Elance Jobs
*/
/*
 * The purpose of this page is to integrate my wordpress website with my elance credential through API provided by elance
 * so i can display the elance search result on my wp site. I can also filter the search result based on the keywords I like 
 * elance return json data if the API call is success then loop the json to display the result
 */
session_start();
require_once('elance-auth-lib.php');
error_reporting(E_ALL);
$api_key="my_api_key";
$consumer_secret_code="my_secret_code";
$keywords="php mysql";
$body="Nothing";

if (!isset($_GET["code"]) && empty($_SESSION['access_token'])) {
	$elance_auth = new ElanceAuthentication();
	$url = $elance_auth->RequestAccessCode($api_key, "http://www.advchaweb.com/elance");

	header("Location:".$url);
}else{				 
	//use elance library
	$elance_auth = new ElanceAuthentication();
	if(empty($_SESSION['access_token'])){
		//get the access token by feed api key and secret code
		$code = $_GET["code"];
		$json = $elance_auth->GetAccessToken($api_key, $consumer_secret_code, $code);
		 
		//Output code
		$access_token=$json->data->access_token;
		$_SESSION['access_token']=$access_token;
	}else{
		$access_token=$_SESSION['access_token'];
	}
	// What page of data are we displaying? Defaults to 1.
	$current_page = 1;
	if (isset($_GET["currentPage"])) { 
		is_numeric($_GET["currentPage"]) or die ("ERROR: currentPage parameter MUST be an integer!");
		intval($_GET["currentPage"]) > 0 or die ("ERROR: currentPage parameter MUST be greater than 0!");
		$current_page = $_GET["currentPage"];
	}
	 
	//elance api url to get the jobs application
	$getJobUrl = "https://api.elance.com/api2/jobs";
	$params=array(
		"access_token"=>$access_token,
		"keywords"=>$keywords,
		"sortCol"=>"numProposals",
		"sortOrder"=>"asc",
		"page"=>$current_page
	);
	$json_response = $elance_auth->ExecRequest($getJobUrl, $access_token, $params);
	if(isset($json_response->errors)){
		$error = $json_response->errors;
		$err_code = "";
		$err_desc = "";
		
		foreach($error as $key => $value){
			$err_code=$value->code;
			$err_desc=$value->description;
		}
		if($err_code=="invalid_token_expired"){
			$url = $elance_auth->RequestAccessCode($api_key, "http://www.advchaweb.com/elance");

			header("Location:".$url);
		}
	}
	if ($json_response == null) {
		die("Retrieved Elance API call, but the response was not valid JSON code.");
	}
	// Generate a success or error response depending on the value of rcode.
	if (isset($json_response->rcode)) { 
		$body = "Call did not complete. JSON error returned.";
	} else {
		if ($json_response->data->numResults == 0) {
			$body = "No records returned.";
		} else {
			$results_per_page = 25;
			$record_num=1+($current_page-1)*$results_per_page;
			// Display paging information. 
			$max_result_num = $json_response->data->page * $results_per_page;
			$first_rec_num = $max_result_num - ($results_per_page - 1);
			$body = "<p>Keywords : ".$keywords."</p><div style=\"width:100%;position:relative;\">\n";
			$body .= "<span style=\"width:37%;position:absolute;left:0;\">Displaying records " . $first_rec_num . " - " . (($json_response->data->page - 1)* $results_per_page + $json_response->data->numResults) . " out of " . $json_response->data->totalResults . " total results</span>\n";
	 
			// Display paging controls. 
			$body .= "<span style=\"width:37%;position:absolute; right:0; text-align:right;\">";
			$sep_text = "";
			if ($json_response->data->page > 1) {
				$body .= "<a href=\"?currentPage=" . ($json_response->data->page - 1) . "\">< Previous</a>&nbsp;";
				$sep_text = "|&nbsp;";
			}
			if ($json_response->data->page != $json_response->data->totalPages) {
				$body .= $sep_text;
				$body .= "<a href=\"?currentPage=" . ($json_response->data->page + 1) . "\">Next ></a>&nbsp;";
			}
			$body .= "</span>\n";
	 
			$body .= "</div>\n";
	 
			$body .= "<div style=\"padding-top:30px;\"><table style=\"width:100%;table-layout:fixed;\">\n"; 
			$body .= "<tr style=\"background-color:#cccccc;font-weight:bold;\">
				<th style=\"width:5%;\">Job ID</th>
				<th style=\"width:18%;\">Job ID<br/>Category</th>
				<th style=\"width:27%;\">Job Title</th>
				<th style=\"width:15%;\">Budget<br/>Date</th>
				<th style=\"width:30%;\">Description</th>
				<th style=\"width:5%;\"># of Bids</th>
				</tr>";
			//displaying result
			foreach ($json_response->data->pageResults as $job_obj) {
				$body .= "<tr class=\"basicRow\">\n";
				$body .= "<td>" . $record_num . "</td>\n";
				$body .= "<td>" . $job_obj->jobId."<br/>".$job_obj->category . "</td>\n";
				$body .= "<td><a href=\"" . $job_obj->jobURL . "\" target=\"_blank\">" . $job_obj->name . "</a><br/>".subkeywordsMatch(strtolower($job_obj->description))."</td>\n";
				$body .= "<td>" . $job_obj->budget . "<br/>".date('d/m/Y', $job_obj->startDate)."<br/>".date('d/m/Y', $job_obj->endDate)."</td>\n";
				$body .= "<td style=\"word-wrap:break-word;\">" . word_trim($job_obj->description, 50, TRUE) . "...</td>\n";
				$body .= "<td style=\"text-align:center;\">" . $job_obj->numProposals . "<td>\n";
				$body .= "</tr>\n";
				$record_num++;
			}
	 
			$body .= "</table></div>";
		}
	}	
}

get_header(); ?>
	<div id="job_result" class="job_result" style="margin-top: -50px;">

		<?php 
			echo $body;

		?>

	</div><!-- #primary -->
<?php //get_sidebar(); ?>
<?php get_footer(); ?>
<?php 
// word_trim courtesy of Jeff Robbins @ Lullabot( http://www.lullabot.com/articles/trim-a-string-to-a-given-word-count)
function word_trim($string, $count, $ellipsis = FALSE){
  $words = explode(' ', $string);
  if (count($words) > $count){
	array_splice($words, $count);
	$string = implode(' ', $words);
	if (is_string($ellipsis)){
	  $string .= $ellipsis;
	}
	elseif ($ellipsis){
	  $string .= '&hellip;';
	}
  }
  return $string;
}

function subkeywordsMatch($string){
	$subkeywords=array("api","instagram","plugin","osclass","magento","symfony","jquery","wordpress","joomla","crm","mailchimp");
	$counter=0;
	$match=array();
	foreach($subkeywords as $sk){
		if(strpos($string,$sk)!==false){
			$counter++;
			$match[]=$sk;
		}
	}
	if($counter)
		return "Match ".$counter." keywords (".implode(",",$match).")";
	else
		return "";
}
?>

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<?php

Template Name: My Elance Jobs

* The purpose of this page is to integrate my wordpress website with my elance credential through API provided by elance

* so i can display the elance search result on my wp site. I can also filter the search result based on the keywords I like

* elance return json data if the API call is success then loop the json to display the result

session_start();

require_once('elance-auth-lib.php');

error_reporting(E_ALL);

$api_key="my_api_key";

$consumer_secret_code="my_secret_code";

$keywords="php mysql";

$body="Nothing";

if (!isset($_GET["code"]) && empty($_SESSION['access_token'])) {

$elance_auth = new ElanceAuthentication();

$url = $elance_auth->RequestAccessCode($api_key, "http://www.advchaweb.com/elance");

header("Location:".$url);

}else{

//use elance library

$elance_auth = new ElanceAuthentication();

if(empty($_SESSION['access_token'])){

//get the access token by feed api key and secret code

$code = $_GET["code"];

$json = $elance_auth->GetAccessToken($api_key, $consumer_secret_code, $code);

//Output code

$access_token=$json->data->access_token;

$_SESSION['access_token']=$access_token;

}else{

$access_token=$_SESSION['access_token'];

}

// What page of data are we displaying? Defaults to 1.

$current_page = 1;

if (isset($_GET["currentPage"])) {

is_numeric($_GET["currentPage"]) or die ("ERROR: currentPage parameter MUST be an integer!");

intval($_GET["currentPage"]) > 0 or die ("ERROR: currentPage parameter MUST be greater than 0!");

$current_page = $_GET["currentPage"];

}

//elance api url to get the jobs application

$getJobUrl = "https://api.elance.com/api2/jobs";

$params=array(

"access_token"=>$access_token,

"keywords"=>$keywords,

"sortCol"=>"numProposals",

"sortOrder"=>"asc",

"page"=>$current_page

);

$json_response = $elance_auth->ExecRequest($getJobUrl, $access_token, $params);

if(isset($json_response->errors)){

$error = $json_response->errors;

$err_code = "";

$err_desc = "";

foreach($error as $key => $value){

$err_code=$value->code;

$err_desc=$value->description;

}

if($err_code=="invalid_token_expired"){

$url = $elance_auth->RequestAccessCode($api_key, "http://www.advchaweb.com/elance");

header("Location:".$url);

}

if ($json_response == null) {

die("Retrieved Elance API call, but the response was not valid JSON code.");

}

// Generate a success or error response depending on the value of rcode.

if (isset($json_response->rcode)) {

$body = "Call did not complete. JSON error returned.";

} else {

if ($json_response->data->numResults == 0) {

$body = "No records returned.";

} else {

$results_per_page = 25;

$record_num=1+($current_page-1)*$results_per_page;

// Display paging information.

$max_result_num = $json_response->data->page * $results_per_page;

$first_rec_num = $max_result_num - ($results_per_page - 1);

$body = "<p>Keywords : ".$keywords."</p><div style=\"width:100%;position:relative;\">\n";

$body .= "<span style=\"width:37%;position:absolute;left:0;\">Displaying records " . $first_rec_num . " - " . (($json_response->data->page - 1)* $results_per_page + $json_response->data->numResults) . " out of " . $json_response->data->totalResults . " total results</span>\n";

// Display paging controls.

$body .= "<span style=\"width:37%;position:absolute; right:0; text-align:right;\">";

$sep_text = "";

if ($json_response->data->page > 1) {

$body .= "<a href=\"?currentPage=" . ($json_response->data->page - 1) . "\">< Previous</a> ";

$sep_text = "| ";

}

if ($json_response->data->page != $json_response->data->totalPages) {

$body .= $sep_text;

$body .= "<a href=\"?currentPage=" . ($json_response->data->page + 1) . "\">Next ></a> ";

}

$body .= "</span>\n";

$body .= "</div>\n";

$body .= "<div style=\"padding-top:30px;\"><table style=\"width:100%;table-layout:fixed;\">\n";

$body .= "<tr style=\"background-color:#cccccc;font-weight:bold;\">

<th style=\"width:18%;\">Job ID<br/>Category</th>

<th style=\"width:27%;\">Job Title</th>

<th style=\"width:15%;\">Budget<br/>Date</th>

<th style=\"width:30%;\">Description</th>

</tr>";

//displaying result

foreach ($json_response->data->pageResults as $job_obj) {

$body .= "<tr class=\"basicRow\">\n";

$body .= "<td>" . $record_num . "</td>\n";

$body .= "<td>" . $job_obj->jobId."<br/>".$job_obj->category . "</td>\n";

$body .= "<td><a href=\"" . $job_obj->jobURL . "\" target=\"_blank\">" . $job_obj->name . "</a><br/>".subkeywordsMatch(strtolower($job_obj->description))."</td>\n";

$body .= "<td>" . $job_obj->budget . "<br/>".date('d/m/Y', $job_obj->startDate)."<br/>".date('d/m/Y', $job_obj->endDate)."</td>\n";

$body .= "<td style=\"word-wrap:break-word;\">" . word_trim($job_obj->description, 50, TRUE) . "...</td>\n";

$body .= "<td style=\"text-align:center;\">" . $job_obj->numProposals . "<td>\n";

$body .= "</tr>\n";

$record_num++;

}

$body .= "</table></div>";

}

get_header(); ?>

<?php

echo $body;

</div>

<?php //get_sidebar(); ?>

<?php get_footer(); ?>

<?php

// word_trim courtesy of Jeff Robbins @ Lullabot( http://www.lullabot.com/articles/trim-a-string-to-a-given-word-count)

function word_trim($string, $count, $ellipsis = FALSE){

$words = explode(' ', $string);

if (count($words) > $count){

array_splice($words, $count);

$string = implode(' ', $words);

if (is_string($ellipsis)){

$string .= $ellipsis;

}

elseif ($ellipsis){

$string .= '…';

}

return $string;

}

function subkeywordsMatch($string){

$subkeywords=array("api","instagram","plugin","osclass","magento","symfony","jquery","wordpress","joomla","crm","mailchimp");

$counter=0;

$match=array();

foreach($subkeywords as $sk){

if(strpos($string,$sk)!==false){

$counter++;

$match[]=$sk;

}

if($counter)

return "Match ".$counter." keywords (".implode(",",$match).")";

else

return "";

}

Just read the code. Try to comprehend it by yourself :). I also need to add a new file ‘elance-auth-lib.php’ for the elance API PHP wrapper in the same directory. The class ‘ElanceAuthentication’ in the file would authenticate the access to the API.

<?php
 
class ElanceAuthentication {
    public $CurlHeaders;
    public $ResponseCode;
 
    private $_AuthorizeUrl = "https://api.elance.com/api2/oauth/authorize";
    private $_AccessTokenUrl = "https://api.elance.com/api2/oauth/token";
 
    public function __construct() {
        $this->CurlHeaders = array();
        $this->ResponseCode = 0;
    }
 
    public function RequestAccessCode ($client_id, $redirect_url) {
        return($this->_AuthorizeUrl . "?client_id=" . $client_id . "&response_type=code&redirect_uri=" . $redirect_url);
    }
 
    // Convert an authorization code from an Elance callback into an access token.
    public function GetAccessToken($client_id, $client_secret, $auth_code) {        
        // Init cUrl.
        $r = $this->InitCurl($this->_AccessTokenUrl);
 
        // Add client ID and client secret to the headers.
        curl_setopt($r, CURLOPT_HTTPHEADER, array (
            "Authorization: Basic " . base64_encode($client_id . ":" . $client_secret),
        ));        
 
        // Assemble POST parameters for the request.
        $post_fields = "code=" . urlencode($auth_code) . "&grant_type=authorization_code";
 
        // Obtain and return the access token from the response.
        curl_setopt($r, CURLOPT_POST, true);
        curl_setopt($r, CURLOPT_POSTFIELDS, $post_fields);
 
        $response = curl_exec($r);
        if ($response == false) {
            die("curl_exec() failed. Error: " . curl_error($r));
        }
 
        //Parse JSON return object.
        return json_decode($response);
    }
 
    private function InitCurl($url) {
        $r = null;
 
        if (($r = @curl_init($url)) == false) {
            header("HTTP/1.1 500", true, 500);
            die("Cannot initialize cUrl session. Is cUrl enabled for your PHP installation?");
        }
 
        curl_setopt($r, CURLOPT_RETURNTRANSFER, 1);
 
        // Decode compressed responses.
        curl_setopt($r, CURLOPT_ENCODING, 1);
 
        // NOTE: If testing locally, add the following lines to use a dummy certificate, and to prevent cUrl from attempting to verify
        // the certificate's authenticity. See http://richardwarrender.com/2007/05/the-secret-to-curl-in-php-on-windows/ for more
        // details on this workaround. If your server has a valid SSL certificate installed, comment out these lines.
        curl_setopt($r, CURLOPT_SSL_VERIFYPEER, false);
        //curl_setopt($r, CURLOPT_CAINFO, "C:\wamp\bin\apache\Apache2.2.21\cacert.crt");
 
        // NOTE: For Fiddler2 debugging.
        //curl_setopt($r, CURLOPT_PROXY, '127.0.0.1:8888');
 
        return($r);
    }
 
    // A generic function that executes an Elance API request. 
    public function ExecRequest($url, $access_token, $get_params) {
        // Create request string.
        //$full_url = http_build_query($url, $get_params);
        $full_url = $url."?".http_build_query($get_params);
 
        //$r = $this->InitCurl($url);
        $r = $this->InitCurl($full_url);
 
        /*curl_setopt($r, CURLOPT_HTTPHEADER, array (
            "Authorization: Basic " . base64_encode($access_token)
        ));
 
        $response = curl_exec($r);
        if ($response == false) {
            die("curl_exec() failed. Error: " . curl_error($r));
        }*/
        $curl_options = array (
			CURLOPT_FRESH_CONNECT => 1,
			CURLOPT_RETURNTRANSFER => 1
			);
		curl_setopt_array($r, $curl_options);
		 
		// Convert response to JSON.
		$json_txt = curl_exec($r);
		if ($json_txt == false) {
			die("Cannot retrieve Elance API URL using cUrl. URL: " . $url);
		}
		curl_close($r); 
		 
		$json_response = json_decode($json_txt);
 
        //Parse JSON return object.
        //return json_decode($response);        
        return $json_response;        
        //return $full_url;        
    }
}
 
?>

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<?php

class ElanceAuthentication {

public $CurlHeaders;

public $ResponseCode;

private $_AuthorizeUrl = "https://api.elance.com/api2/oauth/authorize";

private $_AccessTokenUrl = "https://api.elance.com/api2/oauth/token";

public function __construct() {

$this->CurlHeaders = array();

$this->ResponseCode = 0;

}

public function RequestAccessCode ($client_id, $redirect_url) {

return($this->_AuthorizeUrl . "?client_id=" . $client_id . "&response_type=code&redirect_uri=" . $redirect_url);

}

// Convert an authorization code from an Elance callback into an access token.

public function GetAccessToken($client_id, $client_secret, $auth_code) {

// Init cUrl.

$r = $this->InitCurl($this->_AccessTokenUrl);

// Add client ID and client secret to the headers.

curl_setopt($r, CURLOPT_HTTPHEADER, array (

"Authorization: Basic " . base64_encode($client_id . ":" . $client_secret),

));

// Assemble POST parameters for the request.

$post_fields = "code=" . urlencode($auth_code) . "&grant_type=authorization_code";

// Obtain and return the access token from the response.

curl_setopt($r, CURLOPT_POST, true);

curl_setopt($r, CURLOPT_POSTFIELDS, $post_fields);

$response = curl_exec($r);

if ($response == false) {

die("curl_exec() failed. Error: " . curl_error($r));

}

//Parse JSON return object.

return json_decode($response);

}

private function InitCurl($url) {

$r = null;

if (($r = @curl_init($url)) == false) {

header("HTTP/1.1 500", true, 500);

die("Cannot initialize cUrl session. Is cUrl enabled for your PHP installation?");

}

curl_setopt($r, CURLOPT_RETURNTRANSFER, 1);

// Decode compressed responses.

curl_setopt($r, CURLOPT_ENCODING, 1);

// NOTE: If testing locally, add the following lines to use a dummy certificate, and to prevent cUrl from attempting to verify

// the certificate's authenticity. See http://richardwarrender.com/2007/05/the-secret-to-curl-in-php-on-windows/ for more

// details on this workaround. If your server has a valid SSL certificate installed, comment out these lines.

curl_setopt($r, CURLOPT_SSL_VERIFYPEER, false);

//curl_setopt($r, CURLOPT_CAINFO, "C:\wamp\bin\apache\Apache2.2.21\cacert.crt");

// NOTE: For Fiddler2 debugging.

//curl_setopt($r, CURLOPT_PROXY, '127.0.0.1:8888');

return($r);

}

// A generic function that executes an Elance API request.

public function ExecRequest($url, $access_token, $get_params) {

// Create request string.

//$full_url = http_build_query($url, $get_params);

$full_url = $url."?".http_build_query($get_params);

//$r = $this->InitCurl($url);

$r = $this->InitCurl($full_url);

/*curl_setopt($r, CURLOPT_HTTPHEADER, array (

"Authorization: Basic " . base64_encode($access_token)

));

$response = curl_exec($r);

if ($response == false) {

die("curl_exec() failed. Error: " . curl_error($r));

}*/

$curl_options = array (

CURLOPT_FRESH_CONNECT => 1,

CURLOPT_RETURNTRANSFER => 1

);

curl_setopt_array($r, $curl_options);

// Convert response to JSON.

$json_txt = curl_exec($r);

if ($json_txt == false) {

die("Cannot retrieve Elance API URL using cUrl. URL: " . $url);

}

curl_close($r);

$json_response = json_decode($json_txt);

//Parse JSON return object.

//return json_decode($response);

return $json_response;

//return $full_url;

}

On the wordpress admin, create a new page (not post) with title ‘Elance’ then use template ‘My Elance Jobs’ then Save! It would create a new url: http://www.advchaweb.com/elance/. The url is must be same with our redirect url above!
OK. Now we can use the API from our wordpress page.Just click the link ‘Elance’ or http://www.advchaweb.com/elance
First, It’d redirect us to elance page and please log in!SORRY, ONLY ADMIN CAN SHOW THIS!
After successful login, I supposed to get the authorization page but because it is already closed, I got this page instead 🙁SOMEHOW when I click the ‘Continue to Elance’ button, I still get the authorization page!!!
SORRY, ONLY ADMIN CAN SHOW THIS!OK. Click ‘Allow’ button
It would be redirected back to my wordpress page. Because there is no job anymore on elance, I got no data!SORRY, ONLY ADMIN CAN SHOW THIS!

WordPress Plugin to Connect to Upwork API

Ref: APIS, WORDPRESS TIPS AND TRICKS, USING OAUTH IN WORDPRESS PLUGINS, PART 1: THE BASICS
How to write a WordPress plugin

Make sure you already registered on Upwork (https://upwork.com) and have any Upwork key. If not go to https://developers.upwork.com and get the keys (API Key, API secret, redirect URL, etc). Apply for the API on https://www.upwork.com/services/api/apply
Go into the plugin directory (/wp-content/plugins/) then create a new directory ‘upwork’. then in the new directory, create a new file ‘upwork.php’

Here is our first content in upwork.php file

<?php
/*
 * Plugin Name: WP Upwork 
 * Version: 1 
 * Plugin URI: http://advchaweb.com/
 * Description: A plugin to connect to upwork API
 * Author: Satria Faestha
 * Author URI: http://advchaweb.com/
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * 
 */

<?php

* Plugin Name: WP Upwork

* Version: 1

* Plugin URI: http://advchaweb.com/

* Description: A plugin to connect to upwork API

* Author: Satria Faestha

* Author URI: http://advchaweb.com/

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

* You should have received a copy of the GNU General Public License

* along with this program. If not, see <http://www.gnu.org/licenses/>.

From here, we can see the plugin ‘Upwork’ in the wordpress admin -> plugin Then please ‘Activate’ it.

Create a class ‘WP_Upwork’ and instantiate it in upwork.php file

if ( ! defined( 'ABSPATH' ) ) exit;

if(!class_exists('WP_Upwork'))
{
    class WP_Upwork{
        /**
         * Construct the plugin object
         */
        public function __construct()
        {
            // register actions
        } // END public function __construct
    
        /**
         * Activate the plugin
         */
        public static function activate()
        {
            // Do nothing
        } // END public static function activate
    
        /**
         * Deactivate the plugin
         */     
        public static function deactivate()
        {
            // Do nothing
        } // END public static function deactivate
    } // END class WP_Upwork
} // END if(!class_exists('WP_Upwork'))

//Instantiate WP_Upwork class
if(class_exists('WP_Upwork')){
    // Installation and uninstallation hooks
    register_activation_hook(__FILE__, array('WP_Upwork', 'activate'));
    register_deactivation_hook(__FILE__, array('WP_Upwork', 'deactivate'));

    // instantiate the plugin class
    $wp_upwork = new WP_Upwork();
}

if ( ! defined( 'ABSPATH' ) ) exit;

if(!class_exists('WP_Upwork'))

{

class WP_Upwork{

/**

* Construct the plugin object

public function __construct()

{

// register actions

} // END public function __construct

/**

* Activate the plugin

public static function activate()

{

// Do nothing

} // END public static function activate

/**

* Deactivate the plugin

public static function deactivate()

{

// Do nothing

} // END public static function deactivate

} // END class WP_Upwork

} // END if(!class_exists('WP_Upwork'))

//Instantiate WP_Upwork class

if(class_exists('WP_Upwork')){

// Installation and uninstallation hooks

register_activation_hook(__FILE__, array('WP_Upwork', 'activate'));

register_deactivation_hook(__FILE__, array('WP_Upwork', 'deactivate'));

// instantiate the plugin class

$wp_upwork = new WP_Upwork();

}

Add the setting page
To add the setting page, we need to add actions and callback in constructor of WP_Upwork class.

if(!class_exists('WP_Upwork'))
{
    class WP_Upwork{
        /**
         * Construct the plugin object
         */
        public function __construct()
        {
            // register actions
            // Register plugin settings
            add_action('admin_init', array(&$this, 'admin_init'));
            // Add settings page to menu
            add_action('admin_menu', array(&$this, 'add_menu'));
        } // END public function __construct
    
        ...
    } // END class WP_Upwork
} // END if(!class_exists('WP_Upwork'))

if(!class_exists('WP_Upwork'))

{

class WP_Upwork{

/**

* Construct the plugin object

public function __construct()

{

// register actions

// Register plugin settings

add_action('admin_init', array(&$this, 'admin_init'));

// Add settings page to menu

add_action('admin_menu', array(&$this, 'add_menu'));

} // END public function __construct

...

} // END class WP_Upwork

} // END if(!class_exists('WP_Upwork'))

First we set and register the Upwork setting (API Key and Secret) in WP_Upwork class:

/**
 * hook into WP's admin_init action hook
 */
public function admin_init(){
    // register your plugin's settings
    register_setting( 'wp_upwork-group', 'wp_upwork_api_key' );
    register_setting( 'wp_upwork-group', 'wp_upwork_api_secret' );
    // add your settings section
    add_settings_section(
        'wp_upwork-section', 
        'Upwork API Settings', 
        array( &$this, 'settings_section_wp_upwork'), 
        'wp_upwork_settings'
    );
    // add your setting's fields
    add_settings_field(
        'wp_upwork-api_key', 
        'API Key', 
        array(&$this, 'settings_field_input_text'), 
        'wp_upwork_settings', 
        'wp_upwork-section',
        array(
            'field' => 'wp_upwork_api_key'
        )
    );
    // add your setting's fields
    add_settings_field(
        'wp_upwork-wp_upwork_api_secret', 
        'API Secret', 
        array(&$this, 'settings_field_input_text'), 
        'wp_upwork_settings', 
        'wp_upwork-section',
        array(
            'field' => 'wp_upwork_api_secret'
        )
    );
}

public function settings_section_wp_upwork()
{
    // Think of this as help text for the section.
    echo 'Upwork API Setting:';
}
/**
 * This function provides text inputs for settings fields
 */
public function settings_field_input_text($args)
{
    // Get the field name from the $args array
    $field = esc_attr($args['field']);
    // Get the value of this setting
    $value = get_option($field);
    // echo a proper input type="text"
    echo sprintf('<input type="text" name="%s" id="%s" value="%s" />', $field, $field, $value);
} // END public function settings_field_input_text($args)

/**

* hook into WP's admin_init action hook

public function admin_init(){

// register your plugin's settings

register_setting( 'wp_upwork-group', 'wp_upwork_api_key' );

register_setting( 'wp_upwork-group', 'wp_upwork_api_secret' );

// add your settings section

add_settings_section(

'wp_upwork-section',

'Upwork API Settings',

array( &$this, 'settings_section_wp_upwork'),

'wp_upwork_settings'

);

// add your setting's fields

add_settings_field(

'wp_upwork-api_key',

'API Key',

array(&$this, 'settings_field_input_text'),

'wp_upwork_settings',

'wp_upwork-section',

array(

'field' => 'wp_upwork_api_key'

)

);

// add your setting's fields

add_settings_field(

'wp_upwork-wp_upwork_api_secret',

'API Secret',

array(&$this, 'settings_field_input_text'),

'wp_upwork_settings',

'wp_upwork-section',

array(

'field' => 'wp_upwork_api_secret'

)

);

}

public function settings_section_wp_upwork()

{

// Think of this as help text for the section.

echo 'Upwork API Setting:';

}

/**

* This function provides text inputs for settings fields

public function settings_field_input_text($args)

{

// Get the field name from the $args array

$field = esc_attr($args['field']);

// Get the value of this setting

$value = get_option($field);

// echo a proper input type="text"

echo sprintf('<input type="text" name="%s" id="%s" value="%s" />', $field, $field, $value);

} // END public function settings_field_input_text($args)

Then we add the menu ‘WP Upwork Setting’ in the Settings menu. Let’s add some code in WP_Upwork class:

/**
 * add a menu
 */     
public function add_menu()
{
    // Add a page to manage this plugin's settings
    add_options_page(
        'WP Upwork Settings', 
        'WP Upwork Settings', 
        'manage_options', 
        'wp_upwork', 
        array(&$this, 'plugin_settings_page')
    );
} // END public function add_menu()

/**
 * Menu Callback
 */     
public function plugin_settings_page()
{
    if(!current_user_can('manage_options'))
    {
        wp_die(__('You do not have sufficient permissions to access this page.'));
    }

    // Render the settings template
    //include(sprintf("%s/templates/settings.php", dirname(__FILE__)));
    ?>
    <div class="wrap">
        <h2>Upwork API Settings</h2>
        <p>You'll need to go to the <a href="https://developers.upwork.com">Upwork Developer Page</a> to setup your project and setup the values below.</p>
        <form action="options.php" method="POST">
            <?php settings_fields( 'wp_upwork-group' ); ?>
            <?php do_settings_sections( 'wp_upwork_settings' ); ?>
            <?php submit_button(); ?>
        </form>
    </div>
    <?php
} // END public function plugin_settings_page()

/**

* add a menu

public function add_menu()

{

// Add a page to manage this plugin's settings

add_options_page(

'WP Upwork Settings',

'manage_options',

'wp_upwork',

array(&$this, 'plugin_settings_page')

);

} // END public function add_menu()

/**

* Menu Callback

public function plugin_settings_page()

{

if(!current_user_can('manage_options'))

{

wp_die(__('You do not have sufficient permissions to access this page.'));

}

// Render the settings template

//include(sprintf("%s/templates/settings.php", dirname(__FILE__)));

<h2>Upwork API Settings</h2>

<p>You'll need to go to the <a href="https://developers.upwork.com">Upwork Developer Page</a> to setup your project and setup the values below.</p>

<?php settings_fields( 'wp_upwork-group' ); ?>

<?php do_settings_sections( 'wp_upwork_settings' ); ?>

<?php submit_button(); ?>

</form>

</div>

<?php

} // END public function plugin_settings_page()

Okay. Here is the menu

And here is the ‘Upwork API Settings’ page (http://localhost/works/wordpress_local/wp-admin/options-general.php?page=wp_upwork)

Save the settings
Fill the API Key and API Secret data above given by upwork then click ‘Save Changes’The above values would be saved in the database at ‘wp_options’ table. You can see them in the table like this:Here is my Upwork API Settings:SORRY, ONLY ADMIN CAN SHOW THIS!

Add Setting link next to activate/deactivate link in the plugin management list.
In the WP_Upwork class constructor, add filter ‘plugin_action_links’ like this line:

public function __construct()
{
    ...
    // Add settings link to plugins page
    add_filter( 'plugin_action_links_' . plugin_basename(__FILE__) , array( &$this , 'add_settings_link' ) );
} // END public function __construct

public function __construct()

{

...

// Add settings link to plugins page

add_filter( 'plugin_action_links_' . plugin_basename(__FILE__) , array( &$this , 'add_settings_link' ) );

} // END public function __construct

Then define the function ‘add_settings_link’ in the WP_Upwork class:

// Add the settings link to the plugins page
function add_settings_link($links)
{ 
    $settings_link = '<a href="options-general.php?page=wp_upwork">Settings</a>'; 
    array_unshift($links, $settings_link); 
    return $links; 
}

// Add the settings link to the plugins page

function add_settings_link($links)

{

$settings_link = '<a href="options-general.php?page=wp_upwork">Settings</a>';

array_unshift($links, $settings_link);

return $links;

}

Here is the result looks like:

Refactor our plugin structure a bit. Create a new directory ‘includes’ and add a new file in it ‘settings.php’. I want to move the settings in to the file to make the plugin structure better (Please learn WordPress plugin boilerplate and read How to Build a WordPress Plugin (part 1)).
Here is the content of /includes/settings.php:

<?php
if ( ! defined( 'ABSPATH' ) ) exit;

if(!class_exists('WP_Upwork_Settings'))
{
    class WP_Upwork_Settings{
        /**
         * Construct the plugin object
         */
        public function __construct()
        {
            // register actions
            // Register plugin settings
            add_action('admin_init', array(&$this, 'admin_init'));
            // Add settings page to menu
            add_action('admin_menu', array(&$this, 'add_menu'));
        } // END public function __construct
        
        /**
         * hook into WP's admin_init action hook
         */
        public function admin_init(){
            // register your plugin's settings
            register_setting( 'wp_upwork-group', 'wp_upwork_api_key' );
            register_setting( 'wp_upwork-group', 'wp_upwork_api_secret' );
            // add your settings section
            add_settings_section(
                'wp_upwork-section', 
                __('Upwork API Settings'), 
                array( &$this, 'settings_section_wp_upwork'), 
                'wp_upwork_settings'
            );
            // add your setting's fields
            add_settings_field(
                'wp_upwork-api_key', 
                __('API Key'), 
                array(&$this, 'settings_field_input_text'), 
                'wp_upwork_settings', 
                'wp_upwork-section',
                array(
                    'field' => 'wp_upwork_api_key'
                )
            );
            // add your setting's fields
            add_settings_field(
                'wp_upwork-wp_upwork_api_secret', 
                __('API Secret'), 
                array(&$this, 'settings_field_input_text'), 
                'wp_upwork_settings', 
                'wp_upwork-section',
                array(
                    'field' => 'wp_upwork_api_secret'
                )
            );
        }

        public function settings_section_wp_upwork()
        {
            // Think of this as help text for the section.
            //echo 'Upwork API Setting:';
            _e('Upwork API Setting:','wp_upwork');
        }
        /**
         * This function provides text inputs for settings fields
         */
        public function settings_field_input_text($args)
        {
            // Get the field name from the $args array
            $field = esc_attr($args['field']);
            // Get the value of this setting
            $value = get_option($field);
            // echo a proper input type="text"
            echo sprintf('<input type="text" name="%s" id="%s" value="%s" />', $field, $field, $value);
        } // END public function settings_field_input_text($args)
        
        /**
         * add a menu
         */     
        public function add_menu()
        {
            // Add a page to manage this plugin's settings
            add_options_page(
                __('WP Upwork Settings'), 
                __('WP Upwork Settings'), 
                'manage_options', 
                'wp_upwork', 
                array(&$this, 'plugin_settings_page')
            );
        } // END public function add_menu()

        /**
         * Menu Callback
         */     
        public function plugin_settings_page()
        {
            if(!current_user_can('manage_options'))
            {
                wp_die(__('You do not have sufficient permissions to access this page.'));
            }

            // Render the settings template
            //include(sprintf("%s/templates/settings.php", dirname(__FILE__)));
            ?>
            <div class="wrap">
                <h2><?php _e('Upwork API Settings','wp_upwork'); ?></h2>
                <p><?php _e('You\'ll need to go to the <a href="https://developers.upwork.com">Upwork Developer Page</a> to setup your project and setup the values below.'); ?></p>
                <form action="options.php" method="POST">
                    <?php settings_fields( 'wp_upwork-group' ); ?>
                    <?php do_settings_sections( 'wp_upwork_settings' ); ?>
                    <?php submit_button(); ?>
                </form>
            </div>
            <?php
        } // END public function plugin_settings_page()
    } // END class WP_Upwork_Settings
} // END if(!class_exists('WP_Upwork_Settings'))

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<?php

if ( ! defined( 'ABSPATH' ) ) exit;

if(!class_exists('WP_Upwork_Settings'))

{

class WP_Upwork_Settings{

/**

* Construct the plugin object

public function __construct()

{

// register actions

// Register plugin settings

add_action('admin_init', array(&$this, 'admin_init'));

// Add settings page to menu

add_action('admin_menu', array(&$this, 'add_menu'));

} // END public function __construct

/**

* hook into WP's admin_init action hook

public function admin_init(){

// register your plugin's settings

register_setting( 'wp_upwork-group', 'wp_upwork_api_key' );

register_setting( 'wp_upwork-group', 'wp_upwork_api_secret' );

// add your settings section

add_settings_section(

'wp_upwork-section',

__('Upwork API Settings'),

array( &$this, 'settings_section_wp_upwork'),

'wp_upwork_settings'

);

// add your setting's fields

add_settings_field(

'wp_upwork-api_key',

__('API Key'),

array(&$this, 'settings_field_input_text'),

'wp_upwork_settings',

'wp_upwork-section',

array(

'field' => 'wp_upwork_api_key'

)

);

// add your setting's fields

add_settings_field(

'wp_upwork-wp_upwork_api_secret',

__('API Secret'),

array(&$this, 'settings_field_input_text'),

'wp_upwork_settings',

'wp_upwork-section',

array(

'field' => 'wp_upwork_api_secret'

)

);

}

public function settings_section_wp_upwork()

{

// Think of this as help text for the section.

//echo 'Upwork API Setting:';

_e('Upwork API Setting:','wp_upwork');

}

/**

* This function provides text inputs for settings fields

public function settings_field_input_text($args)

{

// Get the field name from the $args array

$field = esc_attr($args['field']);

// Get the value of this setting

$value = get_option($field);

// echo a proper input type="text"

echo sprintf('<input type="text" name="%s" id="%s" value="%s" />', $field, $field, $value);

} // END public function settings_field_input_text($args)

/**

* add a menu

public function add_menu()

{

// Add a page to manage this plugin's settings

add_options_page(

__('WP Upwork Settings'),

'manage_options',

'wp_upwork',

array(&$this, 'plugin_settings_page')

);

} // END public function add_menu()

/**

* Menu Callback

public function plugin_settings_page()

{

if(!current_user_can('manage_options'))

{

wp_die(__('You do not have sufficient permissions to access this page.'));

}

// Render the settings template

//include(sprintf("%s/templates/settings.php", dirname(__FILE__)));

<p><?php _e('You\'ll need to go to the <a href="https://developers.upwork.com">Upwork Developer Page</a> to setup your project and setup the values below.'); ?></p>

<?php settings_fields( 'wp_upwork-group' ); ?>

<?php do_settings_sections( 'wp_upwork_settings' ); ?>

<?php submit_button(); ?>

</form>

</div>

<?php

} // END public function plugin_settings_page()

} // END class WP_Upwork_Settings

} // END if(!class_exists('WP_Upwork_Settings'))

And here is our main plugin file ‘upwork.php’ content:

if ( ! defined( 'ABSPATH' ) ) exit;

if( ! defined('WP_UPWORK_PLUGIN_DIR' ) ) {
    define('WP_UPWORK_PLUGIN_DIR', dirname(__FILE__));
}

if(!class_exists('WP_Upwork'))
{
    class WP_Upwork{
        /**
         * Construct the plugin object
         */
        public function __construct()
        {
            //Initialize settings
            require_once(WP_UPWORK_PLUGIN_DIR . '/includes/settings.php');
            $WP_Upwork_Settings=new WP_Upwork_Settings();
            // Add settings link to plugins page
            add_filter( 'plugin_action_links_' . plugin_basename(__FILE__) , array( &$this , 'add_settings_link' ) );
        }
        /**
         * Activate the plugin
         */
        public static function activate()
        {
            // Do nothing
        } // END public static function activate
    
        /**
         * Deactivate the plugin
         */     
        public static function deactivate()
        {
            // Do nothing
        } // END public static function deactivate
        
        // Add the settings link to the plugins page
        function add_settings_link($links)
        { 
            $settings_link = '<a href="options-general.php?page=wp_upwork">Settings</a>'; 
            array_unshift($links, $settings_link); 
            return $links; 
        }
    } // END class WP_Upwork
} // END if(!class_exists('WP_Upwork'))

//Instantiate WP_Upwork class
if(class_exists('WP_Upwork')){
    // Installation and uninstallation hooks
    register_activation_hook(__FILE__, array('WP_Upwork', 'activate'));
    register_deactivation_hook(__FILE__, array('WP_Upwork', 'deactivate'));

    // instantiate the plugin class
    $wp_upwork = new WP_Upwork();
}

if ( ! defined( 'ABSPATH' ) ) exit;

if( ! defined('WP_UPWORK_PLUGIN_DIR' ) ) {

define('WP_UPWORK_PLUGIN_DIR', dirname(__FILE__));

}

if(!class_exists('WP_Upwork'))

{

class WP_Upwork{

/**

* Construct the plugin object

public function __construct()

{

//Initialize settings

require_once(WP_UPWORK_PLUGIN_DIR . '/includes/settings.php');

$WP_Upwork_Settings=new WP_Upwork_Settings();

// Add settings link to plugins page

add_filter( 'plugin_action_links_' . plugin_basename(__FILE__) , array( &$this , 'add_settings_link' ) );

}

/**

* Activate the plugin

public static function activate()

{

// Do nothing

} // END public static function activate

/**

* Deactivate the plugin

public static function deactivate()

{

// Do nothing

} // END public static function deactivate

// Add the settings link to the plugins page

function add_settings_link($links)

{

$settings_link = '<a href="options-general.php?page=wp_upwork">Settings</a>';

array_unshift($links, $settings_link);

return $links;

}

} // END class WP_Upwork

} // END if(!class_exists('WP_Upwork'))

//Instantiate WP_Upwork class

if(class_exists('WP_Upwork')){

// Installation and uninstallation hooks

register_activation_hook(__FILE__, array('WP_Upwork', 'activate'));

register_deactivation_hook(__FILE__, array('WP_Upwork', 'deactivate'));

// instantiate the plugin class

$wp_upwork = new WP_Upwork();

}

Somehow I can’t put the filter ‘plugin_action_links_’ . plugin_basename(__FILE__)’ in ‘WP_Upwork_Settings’ class! The setting link can’t be displayed in the plugin main list!

Now I want to connect to Upwork API with My API key and API Secret provided by Upwork. When the connection is success, I would get the access token! I need to store the token to get more access from Upwork like searching the jobs and many more.
NOTE: I MADE A WRONG THING HERE! WHAT I THOUGHT AS ACCESS TOKEN ACTUALLY IS A REQUEST TOKEN! AND FINALLY IT’S NOT WORKING FROM HERE #9 UNTIL #13
Modify /includes/settings.php to show the token below the API Key and Secret (The token must be from Upwork so I dont have to type it manually). The screnario is every ‘Save’ button is pressed, beside the keys, the token would be updated as well. So in ‘WP_Upwork_Settings’ class constructor, add this:

class WP_Upwork_Settings{
    /**
     * Construct the plugin object
     */
    protected $action       = 'wp_upwork';
    protected $option_name  = 'wp_upwork';

    public function __construct()
    {
        ...
        // Get access token after saving data
        add_action('init', array(&$this, 'get_access_token'));
    } // END public function __construct

class WP_Upwork_Settings{

/**

* Construct the plugin object

protected $action = 'wp_upwork';

protected $option_name = 'wp_upwork';

public function __construct()

{

...

// Get access token after saving data

add_action('init', array(&$this, 'get_access_token'));

} // END public function __construct

Then show the label for the access token in ‘admin_init’ and ‘settings_field_label’ function:

public function admin_init(){
    // register your plugin's settings
    ...
    register_setting( 'wp_upwork-group', 'wp_upwork_access_token' );
    ...
    // add your setting's fields
    add_settings_field(
        'wp_upwork-wp_upwork_access_token', 
        __('Access Token'), 
        array(&$this, 'settings_field_label'), 
        'wp_upwork_settings', 
        'wp_upwork-section',
        array(
            'field' => 'wp_upwork_access_token'
        )
    );
}
...
/**
 * This function provides label for settings fields
 */
public function settings_field_label($args)
{
    // Get the field name from the $args array
    $field = esc_attr($args['field']);
    // Get the value of this setting
    $value = get_option($field);
    // echo a proper input type="text"
    echo sprintf('<label name="%s" id="%s">%s</label>', $field, $field, $value);
} // END public function settings_field_input_text($args)

public function admin_init(){

// register your plugin's settings

...

register_setting( 'wp_upwork-group', 'wp_upwork_access_token' );

...

// add your setting's fields

add_settings_field(

'wp_upwork-wp_upwork_access_token',

__('Access Token'),

array(&$this, 'settings_field_label'),

'wp_upwork_settings',

'wp_upwork-section',

array(

'field' => 'wp_upwork_access_token'

)

);

}

...

/**

* This function provides label for settings fields

public function settings_field_label($args)

{

// Get the field name from the $args array

$field = esc_attr($args['field']);

// Get the value of this setting

$value = get_option($field);

// echo a proper input type="text"

echo sprintf('<label name="%s" id="%s">%s</label>', $field, $field, $value);

} // END public function settings_field_input_text($args)

Modify ‘plugin_settings_page’ function to add a new hidden value ‘wp_nonce_field’ and change the button title to ‘Save and Get Access Token’.

public function plugin_settings_page()
{
    ...
    ?>
    <div class="wrap">
        <h2><?php _e('Upwork API Settings','wp_upwork'); ?></h2>
        <p><?php _e('You\'ll need to go to the <a href="https://developers.upwork.com">Upwork Developer Page</a> to setup your project and setup the values below.'); ?></p>
        <form action="options-general.php?page=wp_upwork" method="POST">
            <?php settings_fields( 'wp_upwork-group' ); ?>
            <?php wp_nonce_field( $this->action, $this->option_name . '_nonce', FALSE ); ?>
            <?php do_settings_sections( 'wp_upwork_settings' ); ?>
            <?php submit_button(__('Save and Get Access Token')); ?>
        </form>
    </div>
    <?php
} // END public function plugin_settings_page()

public function plugin_settings_page()

{

...

<p><?php _e('You\'ll need to go to the <a href="https://developers.upwork.com">Upwork Developer Page</a> to setup your project and setup the values below.'); ?></p>

<?php settings_fields( 'wp_upwork-group' ); ?>

<?php wp_nonce_field( $this->action, $this->option_name . '_nonce', FALSE ); ?>

<?php do_settings_sections( 'wp_upwork_settings' ); ?>

<?php submit_button(__('Save and Get Access Token')); ?>

</form>

</div>

<?php

} // END public function plugin_settings_page()

The hidden value would be submitted and be caught to inspect the keys and get the access token in ‘get_access_token’ function.

/**
 * Get access token after saving data
 */     
public function get_access_token()
{
    if(isset($_POST[ $this->option_name . '_nonce' ])){
        if ( wp_verify_nonce( $_POST[ $this->option_name . '_nonce' ], $this->action ) ){
            if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){
                /*require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Config.php');
                NO MORE INCLUDE.USE AUTOLOAD INSTEAD*/
                $api_key=$_POST[ 'wp_upwork_api_key' ];
                $api_secret=$_POST[ 'wp_upwork_api_secret' ];
                $my_config=array(
                    'consumerKey'       => $api_key,
                    'consumerSecret'    => $api_secret,
                    'accessToken'       => NULL,       // got access token
                    'accessSecret'      => NULL,      // got access secret
                    'requestToken'      => NULL,      // got request token
                    'requestSecret'     => NULL,     // got request secret
                    'verifySsl'         => false,
                    'mode'              => 'web',
                    'authType'          => 'OAuthPHPLib',
                    'debug'             => false
                );
                $config=new \Upwork\API\Config($my_config);
                //echo $config::get('consumerKey');
                $client=new \Upwork\API\Client($config);
                //$requestTokenInfo = $client->getRequestToken();
                var_dump($client->getRequestToken());
            }
            exit;
        }
    }
} // END public function admin_post()

/**

* Get access token after saving data

public function get_access_token()

{

if(isset($_POST[ $this->option_name . '_nonce' ])){

if ( wp_verify_nonce( $_POST[ $this->option_name . '_nonce' ], $this->action ) ){

if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){

/*require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Config.php');

NO MORE INCLUDE.USE AUTOLOAD INSTEAD*/

$api_key=$_POST[ 'wp_upwork_api_key' ];

$api_secret=$_POST[ 'wp_upwork_api_secret' ];

$my_config=array(

'consumerKey' => $api_key,

'consumerSecret' => $api_secret,

'accessToken' => NULL, // got access token

'accessSecret' => NULL, // got access secret

'requestToken' => NULL, // got request token

'requestSecret' => NULL, // got request secret

'verifySsl' => false,

'mode' => 'web',

'authType' => 'OAuthPHPLib',

'debug' => false

);

$config=new \Upwork\API\Config($my_config);

//echo $config::get('consumerKey');

$client=new \Upwork\API\Client($config);

//$requestTokenInfo = $client->getRequestToken();

var_dump($client->getRequestToken());

}

exit;

}

} // END public function admin_post()

There is an important setting to pass the configuration beside ‘consumer key’ and ‘consumer secret’, it’s ‘authType’. I tried ‘OAuth1’ but it didn’t work. the work is ‘OAuthPHPLib’.

Use composer to download the Upwork API for PHP (https://github.com/upwork/php-upwork). Create a new composer.json file in our main plugin directory. Here is the content:

{
    "name": "advcha/upwork",
    "require": {
        "upwork/php-upwork": "dev-master"
    }
}

{

"name": "advcha/upwork",

"require": {

"upwork/php-upwork": "dev-master"

}

Now use terminal and download the API PHP library

teddy@teddy-K43SJ:~$ cd Documents/works/wordpress_local/wp-content/plugins/upwork/
teddy@teddy-K43SJ:~/Documents/works/wordpress_local/wp-content/plugins/upwork$ composer update
Loading composer repositories with package information
Updating dependencies (including require-dev)
  - Installing upwork/php-upwork (dev-master b48b104)
    Downloading: 100%         

upwork/php-upwork suggests installing ext-oauth (This extension from PECL provides OAuth consumer and provider bindings. See more under http://www.php.net/oauth)
Writing lock file
Generating autoload files

teddy@teddy-K43SJ:~$ cd Documents/works/wordpress_local/wp-content/plugins/upwork/

teddy@teddy-K43SJ:~/Documents/works/wordpress_local/wp-content/plugins/upwork$ composer update

Loading composer repositories with package information

Updating dependencies (including require-dev)

- Installing upwork/php-upwork (dev-master b48b104)

Downloading: 100%

upwork/php-upwork suggests installing ext-oauth (This extension from PECL provides OAuth consumer and provider bindings. See more under http://www.php.net/oauth)

Writing lock file

Generating autoload files

This would create a new directory ‘vendor’ in the main our plugin directory. The API would be there!
Read how to use autoload and composer for developing wordpress plugin: Improving WordPress Development Workflow with Composer, Managing Your WordPress Site with Git and Composer Part 2 – Using Composer to Manage Themes and Plugins and How To Use Autoloading And A Plugin Container In WordPress Plugins.

We need to add the autoload in upwork.php file so we can use the API library:

require __DIR__ . '/vendor/autoload.php';

1	require __DIR__ . '/vendor/autoload.php';

With this only single line, we dont need to include/require the API library manually like this (/includes/settings.php at ‘admin_post’ function):

/*require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Config.php');
require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Client.php');
require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Debug.php');
require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Interfaces/Client.php');
require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/AuthTypes/AbstractOAuth.php');
require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/AuthTypes/OAuth1.php');*/

/*require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Config.php');

require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Client.php');

require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Debug.php');

require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/Interfaces/Client.php');

require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/AuthTypes/AbstractOAuth.php');

require_once(WP_UPWORK_PLUGIN_DIR . '/src/Upwork/API/AuthTypes/OAuth1.php');*/

Here is how it looksWhen the button is pressed, if nothing wrong the access token and the access token secret would be revealed like this:SORRY, ONLY ADMIN CAN SHOW THIS!

Now I want to store the tokens values in database so later we can get the values and use its for Upwork API functions.
Modify ‘get_access_token’ function in /includes/settings.php file to get the tokens and save its. I use ‘update_option’ function to do its (https://codex.wordpress.org/Function_Reference/update_option)

public function get_access_token()
{
    if(isset($_POST[ $this->option_name . '_nonce' ])){
        if ( wp_verify_nonce( $_POST[ $this->option_name . '_nonce' ], $this->action ) ){
            if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){
                ...
                $client=new \Upwork\API\Client($config);
                $requestTokenInfo = $client->getRequestToken();
                if(isset($requestTokenInfo['oauth_token']) && isset($requestTokenInfo['oauth_token_secret'])){
                    //save/update the tokens in database
                    update_option('wp_upwork_access_token', $requestTokenInfo['oauth_token']);
                    update_option('wp_upwork_access_token_secret', $requestTokenInfo['oauth_token_secret']);
                }else{
                    var_dump($client->getRequestToken());
                    exit;
                }
                
            }
            //exit;
        }
    }
} // END public function get_access_token()

public function get_access_token()

{

if(isset($_POST[ $this->option_name . '_nonce' ])){

if ( wp_verify_nonce( $_POST[ $this->option_name . '_nonce' ], $this->action ) ){

if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){

...

$client=new \Upwork\API\Client($config);

$requestTokenInfo = $client->getRequestToken();

if(isset($requestTokenInfo['oauth_token']) && isset($requestTokenInfo['oauth_token_secret'])){

//save/update the tokens in database

update_option('wp_upwork_access_token', $requestTokenInfo['oauth_token']);

update_option('wp_upwork_access_token_secret', $requestTokenInfo['oauth_token_secret']);

}else{

var_dump($client->getRequestToken());

exit;

}

//exit;

}

} // END public function get_access_token()

If everything right, here is how it would looks like

<OLD>
You can also check the tokens values. Not only the value for access token (‘wp_upwork_access_token’) but also for access token secret’s value (‘wp_upwork_access_token_secret’). No reason to display the secret’s value here.
</OLD>
<NEW>
Actually I GOT THE REQUEST TOKEN ABOVE NOT THE ACCESS TOKEN!! SO UPWORK GAVE REQUEST TOKEN FIRST THEN GIVE BACK THE ACCESS TOKEN IF SUCCESS!
READ THIS FOR THE WORKFLOW: https://developers.upwork.com/?lang=php#authentication_oauth-10
</NEW>

I tried to get the access token (actually I just realized I got the request token not the access token)
I MODIFY ‘get_access_token’ function

/**
 * Get access token after saving data
 */     
public function get_access_token()
{
    if( !session_id() )
        session_start();
        
    if(isset($_POST[ $this->option_name . '_nonce' ]) || (isset($_SESSION['oauth_token']) && isset($_SESSION['oauth_token_secret'])) || (isset($_GET['oauth_token']) && isset($_SESSION['oauth_verifier']))){
        //first
        $api_key=get_option('wp_upwork_api_key');
        $api_secret=get_option('wp_upwork_api_secret');
        /*if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){
            $api_key=$_POST[ 'wp_upwork_api_key' ];
            $api_secret=$_POST[ 'wp_upwork_api_secret' ];
        }*/
        $request_token=$_SESSION['oauth_token'];
        $request_token_secret=$_SESSION['oauth_token_secret'];
        $verifier=$_GET['oauth_verifier'];

        $access_token=$_SESSION['access_token'];
        $access_secret=$_SESSION['access_secret'];
                
        $my_config=array(
            'consumerKey'       => $api_key,
            'consumerSecret'    => $api_secret,
            'accessToken'       => $access_token,             // got access token
            'accessSecret'      => $access_secret,            // got access secret
            'requestToken'      => $request_token,            // got request token
            'requestSecret'     => $request_token_secret,     // got request secret
            'verifier'          => $verifier,
            'verifySsl'         => false,
            'mode'              => 'web',
            'authType'          => 'OAuthPHPLib',
            'debug'             => false
        );
        $config=new \Upwork\API\Config($my_config);
        $client=new \Upwork\API\Client($config);
                
        if ( wp_verify_nonce( $_POST[ $this->option_name . '_nonce' ], $this->action ) && (empty($_SESSION['oauth_token']) && empty($_SESSION['access_token'])) ){
            if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){
                $requestTokenInfo = $client->getRequestToken();
                if(isset($requestTokenInfo['oauth_token']) && isset($requestTokenInfo['oauth_token_secret'])){
                    
                    $_SESSION['oauth_token']=$requestTokenInfo['oauth_token'];
                    $_SESSION['oauth_token_secret']=$requestTokenInfo['oauth_token_secret'];
                    // request authorization
                    $client->auth();
                    //var_dump($accessTokenInfo);
                    //exit;
                }else{
                    var_dump($client->getRequestToken());
                    exit;
                }
                
            }
            //exit;
        }elseif(empty($_SESSION['access_token'])){
            //get authorization
            $accessTokenInfo = $client->auth();
            var_dump($accessTokenInfo);
            if($accessTokenInfo){
                $_SESSION['access_token']   = $accessTokenInfo['access_token'];
                $_SESSION['access_secret']  = $accessTokenInfo['access_secret'];
                
                //save/update the tokens in database
                update_option('wp_upwork_access_token',$accessTokenInfo['access_token']);
                update_option('wp_upwork_access_token_secret',$accessTokenInfo['access_secret']);
            }
            //exit;
        }
        
        if ($_SESSION['access_token']) {
            // clean up session data
            unset($_SESSION['request_token']);
            unset($_SESSION['request_secret']);
            // gets info of the authenticated user
            $auth = new \Upwork\API\Routers\Auth($client);
            $info = $auth->getUserInfo();
            print_r($info);
        }
    }
    
    
} // END public function get_access_token()

/**

* Get access token after saving data

public function get_access_token()

{

if( !session_id() )

session_start();

if(isset($_POST[ $this->option_name . '_nonce' ]) || (isset($_SESSION['oauth_token']) && isset($_SESSION['oauth_token_secret'])) || (isset($_GET['oauth_token']) && isset($_SESSION['oauth_verifier']))){

//first

$api_key=get_option('wp_upwork_api_key');

$api_secret=get_option('wp_upwork_api_secret');

/*if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){

$api_key=$_POST[ 'wp_upwork_api_key' ];

$api_secret=$_POST[ 'wp_upwork_api_secret' ];

}*/

$request_token=$_SESSION['oauth_token'];

$request_token_secret=$_SESSION['oauth_token_secret'];

$verifier=$_GET['oauth_verifier'];

$access_token=$_SESSION['access_token'];

$access_secret=$_SESSION['access_secret'];

$my_config=array(

'consumerKey' => $api_key,

'consumerSecret' => $api_secret,

'accessToken' => $access_token, // got access token

'accessSecret' => $access_secret, // got access secret

'requestToken' => $request_token, // got request token

'requestSecret' => $request_token_secret, // got request secret

'verifier' => $verifier,

'verifySsl' => false,

'mode' => 'web',

'authType' => 'OAuthPHPLib',

'debug' => false

);

$config=new \Upwork\API\Config($my_config);

$client=new \Upwork\API\Client($config);

if ( wp_verify_nonce( $_POST[ $this->option_name . '_nonce' ], $this->action ) && (empty($_SESSION['oauth_token']) && empty($_SESSION['access_token'])) ){

if ( isset ( $_POST[ 'wp_upwork_api_key' ] ) && isset ( $_POST[ 'wp_upwork_api_secret' ] )){

$requestTokenInfo = $client->getRequestToken();

if(isset($requestTokenInfo['oauth_token']) && isset($requestTokenInfo['oauth_token_secret'])){

$_SESSION['oauth_token']=$requestTokenInfo['oauth_token'];

$_SESSION['oauth_token_secret']=$requestTokenInfo['oauth_token_secret'];

// request authorization

$client->auth();

//var_dump($accessTokenInfo);

//exit;

}else{

var_dump($client->getRequestToken());

exit;

}

//exit;

}elseif(empty($_SESSION['access_token'])){

//get authorization

$accessTokenInfo = $client->auth();

var_dump($accessTokenInfo);

if($accessTokenInfo){

$_SESSION['access_token'] = $accessTokenInfo['access_token'];

$_SESSION['access_secret'] = $accessTokenInfo['access_secret'];

//save/update the tokens in database

update_option('wp_upwork_access_token',$accessTokenInfo['access_token']);

update_option('wp_upwork_access_token_secret',$accessTokenInfo['access_secret']);

}

//exit;

}

if ($_SESSION['access_token']) {

// clean up session data

unset($_SESSION['request_token']);

unset($_SESSION['request_secret']);

// gets info of the authenticated user

$auth = new \Upwork\API\Routers\Auth($client);

$info = $auth->getUserInfo();

print_r($info);

}

} // END public function get_access_token()

LIKE I SAID ABOVE, IT DIDN’T WORK

https://www.upwork.com/services/api/www.advchaweb.com/upwork?oauth_token=708638d60eee72f4c7c133a2617b15ef&oauth_verifier=b57428447a10ef831db125a1c9f6e648
IT SHOULD BE LIKE:
http://localhost/works/wordpress_local/wp-admin/options-general.php?page=wp_upwork&oauth_token=63c1ab57d81ef2a120dc122255f252fd&oauth_verifier=4601823dab3c049d2d71be0f76a48a7cUNTIL HERE, IT’S NOT WORKING AS EXPECTED. I NEED TO TRY THIS SAMPLE https://github.com/upwork/php-upwork/blob/master/example/web.php
I MAKE THE SAMPLE LOCALLY: http://localhost/works/upwork_api/ AND IT’S WORKING FOR THE FIRST TIME (NOT WORKING AFTER THAT. MEANS NO DATA CAN I GET FROM UPWORK!!!)
SORRY, ONLY ADMIN CAN SHOW THIS!
After a few hours I tried again to call the Upwork API via http://localhost/works/upwork_api AND it’s working again. Actually to get the access token and call a function (like User), it takes four web call.
SORRY, ONLY ADMIN CAN SHOW THIS!

Because I failed to get the access token from ‘get_access_token’ function, I tried to use Custom Page Template (Please read Add Page Templates to WordPress with a Plugin) like I used to use it for Elance API. But it different here. I dont have to inject the php file in the active theme. I can use it from my plugin!
Okay. I need to clean my code and remove the previous changes above (from #9 and #14) about the tokens field and the ‘get_access_token’ function.
SORRY, ONLY ADMIN CAN SHOW THIS!
SO I BACK TO THE PREVIOUS CODE WHERE THE WP_Upwork plugin in the admin page only to store API Key and API Secret!
Back to our custom page template, create a new file ‘template.php’ in /includes/ directory. this file would consist of a class ‘WP_Upwork_Template’. This class would get the template file, show it on the page/post page dropdown template and render/view it.

<?php
if ( ! defined( 'ABSPATH' ) ) exit;

if(!class_exists('WP_Upwork_Template'))
{
    class WP_Upwork_Template{
        
        /**
         * A reference to an instance of this class.
         */
        private static $instance;
        /**
         * The array of templates that this plugin tracks.
         */
        protected $templates;
        /**
         * Returns an instance of this class. 
         */
        public static function get_instance() {
            if ( null == self::$instance ) {
                self::$instance = new WP_Upwork_Template();
            } 
            return self::$instance;
        } 
        /**
         * Construct the plugin object
         */
        public function __construct()
        {
            $this->templates = array();
            
            // Add a filter to the attributes metabox to inject template into the cache.
            if ( version_compare( floatval( get_bloginfo( 'version' ) ), '4.7', '<' ) ) { // 4.6 and older
                add_filter(
                    'page_attributes_dropdown_pages_args',
                    array( &$this, 'register_upwork_templates' )
                );
            } else { // Add a filter to the wp 4.7 version attributes metabox
                add_filter(
                    'theme_page_templates', array( &$this, 'add_upwork_template' )
                );
            }
            // Add a filter to the save post to inject out template into the page cache
            add_filter(
                'wp_insert_post_data', 
                array( &$this, 'register_upwork_templates' ) 
            );
            // Add a filter to the template include to determine if the page has our 
            // template assigned and return it's path
            add_filter(
                'template_include', 
                array( &$this, 'view_upwork_template') 
            );
            // Add your templates to this array.
            $this->templates = array(
                'upwork-template.php' => 'Upwork Template',
            );
        } // END public function __construct
        
        /**
         * Adds our template to the page dropdown for v4.7+
         *
         */
        public function add_upwork_template( $posts_templates ) {
            $posts_templates = array_merge( $posts_templates, $this->templates );
            return $posts_templates;
        }
        /**
         * Adds our template to the pages cache in order to trick WordPress
         * into thinking the template file exists where it doens't really exist.
         *
         */
        public function register_upwork_templates( $atts ) {
            // Create the key used for the themes cache
            $cache_key = 'page_templates-' . md5( get_theme_root() . '/' . get_stylesheet() );
            // Retrieve the cache list. 
            // If it doesn't exist, or it's empty prepare an array
            $templates = wp_get_theme()->get_page_templates();
            if ( empty( $templates ) ) {
                $templates = array();
            } 
            // New cache, therefore remove the old one
            wp_cache_delete( $cache_key , 'themes');
            // Now add our template to the list of templates by merging our templates
            // with the existing templates array from the cache.
            $templates = array_merge( $templates, $this->templates );
            // Add the modified cache to allow WordPress to pick it up for listing
            // available templates
            wp_cache_add( $cache_key, $templates, 'themes', 1800 );
            return $atts;
        } 
        /**
         * Checks if the template is assigned to the page
         */
        public function view_upwork_template( $template ) {
            
            // Get global post
            global $post;
            // Return template if post is empty
            if ( ! $post ) {
                return $template;
            }
            // Return default template if we don't have a custom one defined
            if ( !isset( $this->templates[get_post_meta( 
                $post->ID, '_wp_page_template', true 
            )] ) ) {
                return $template;
            } 
            $file = plugin_dir_path(__FILE__). get_post_meta( 
                $post->ID, '_wp_page_template', true
            );
            // Just to be safe, we check if the file exist first
            if ( file_exists( $file ) ) {
                echo "File exist:";
                return $file;
            } else {
                echo "File NOT exist:".$file;
            }
            // Return template
            return $template;
        }
        
    } // END class WP_Upwork_Template
} // END if(!class_exists('WP_Upwork_Template'))

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

<?php

if ( ! defined( 'ABSPATH' ) ) exit;

if(!class_exists('WP_Upwork_Template'))

{

class WP_Upwork_Template{

/**

* A reference to an instance of this class.

private static $instance;

/**

* The array of templates that this plugin tracks.

protected $templates;

/**

* Returns an instance of this class.

public static function get_instance() {

if ( null == self::$instance ) {

self::$instance = new WP_Upwork_Template();

}

return self::$instance;

}

/**

* Construct the plugin object

public function __construct()

{

$this->templates = array();

// Add a filter to the attributes metabox to inject template into the cache.

if ( version_compare( floatval( get_bloginfo( 'version' ) ), '4.7', '<' ) ) { // 4.6 and older

add_filter(

'page_attributes_dropdown_pages_args',

array( &$this, 'register_upwork_templates' )

);

} else { // Add a filter to the wp 4.7 version attributes metabox

add_filter(

'theme_page_templates', array( &$this, 'add_upwork_template' )

);

}

// Add a filter to the save post to inject out template into the page cache

add_filter(

'wp_insert_post_data',

array( &$this, 'register_upwork_templates' )

);

// Add a filter to the template include to determine if the page has our

// template assigned and return it's path

add_filter(

'template_include',

array( &$this, 'view_upwork_template')

);

// Add your templates to this array.

$this->templates = array(

'upwork-template.php' => 'Upwork Template',

);

} // END public function __construct

/**

* Adds our template to the page dropdown for v4.7+

public function add_upwork_template( $posts_templates ) {

$posts_templates = array_merge( $posts_templates, $this->templates );

return $posts_templates;

}

/**

* Adds our template to the pages cache in order to trick WordPress

* into thinking the template file exists where it doens't really exist.

public function register_upwork_templates( $atts ) {

// Create the key used for the themes cache

$cache_key = 'page_templates-' . md5( get_theme_root() . '/' . get_stylesheet() );

// Retrieve the cache list.

// If it doesn't exist, or it's empty prepare an array

$templates = wp_get_theme()->get_page_templates();

if ( empty( $templates ) ) {

$templates = array();

}

// New cache, therefore remove the old one

wp_cache_delete( $cache_key , 'themes');

// Now add our template to the list of templates by merging our templates

// with the existing templates array from the cache.

$templates = array_merge( $templates, $this->templates );

// Add the modified cache to allow WordPress to pick it up for listing

// available templates

wp_cache_add( $cache_key, $templates, 'themes', 1800 );

return $atts;

}

/**

* Checks if the template is assigned to the page

public function view_upwork_template( $template ) {

// Get global post

global $post;

// Return template if post is empty

if ( ! $post ) {

return $template;

}

// Return default template if we don't have a custom one defined

if ( !isset( $this->templates[get_post_meta(

$post->ID, '_wp_page_template', true

)] ) ) {

return $template;

}

$file = plugin_dir_path(__FILE__). get_post_meta(

$post->ID, '_wp_page_template', true

);

// Just to be safe, we check if the file exist first

if ( file_exists( $file ) ) {

echo "File exist:";

return $file;

} else {

echo "File NOT exist:".$file;

}

// Return template

return $template;

}

} // END class WP_Upwork_Template

} // END if(!class_exists('WP_Upwork_Template'))

The template name is in a file ‘upwork-template.php’ in the same directory (/includes/). this file is the main page to connect to Upwork API (authenticate, authorize/get access token and call the Upwork API functions). This content looks like same with https://github.com/upwork/php-upwork/blob/master/example/web.php. Only API key and API secret I got from database. For a test only and to prove it can work as expected, here is the file content:

<?php
/*
 * Template Name: Upwork Template
 * Description: A Page Template for displaying Upwork API capability.
 */

session_start();
require WP_UPWORK_PLUGIN_DIR . '/vendor/autoload.php';
$config = new \Upwork\API\Config(
    array(
        'consumerKey'       => get_option('wp_upwork_api_key'),  // SETUP YOUR CONSUMER KEY
        'consumerSecret'    => get_option('wp_upwork_api_secret'),                  // SETUP YOUR KEY SECRET
        'accessToken'       => $_SESSION['access_token'],       // got access token
        'accessSecret'      => $_SESSION['access_secret'],      // got access secret
        'requestToken'      => $_SESSION['request_token'],      // got request token
        'requestSecret'     => $_SESSION['request_secret'],     // got request secret
        'verifier'          => $_GET['oauth_verifier'],         // got oauth verifier after authorization
        'mode'              => 'web',                           // can be 'nonweb' for console apps (default),
                                                                // and 'web' for web-based apps
        'debug'             => true, // enables debug mode. Note that enabling debug in web-based applications can block redirects
        'authType'          => 'OAuthPHPLib' // your own authentication type, see AuthTypes directory
    )
);
$client = new \Upwork\API\Client($config);
//var_dump($_SESSION);exit;
if (empty($_SESSION['request_token']) && empty($_SESSION['access_token'])) {
    // we need to get and save the request token. It will be used again
    // after the redirect from the Upwork site
    $requestTokenInfo = $client->getRequestToken();
    $_SESSION['request_token']  = $requestTokenInfo['oauth_token'];
    $_SESSION['request_secret'] = $requestTokenInfo['oauth_token_secret'];
    // request authorization
    $client->auth();
} elseif (empty($_SESSION['access_token'])) {
    // the callback request should be pointed to this script as well as
    // the request access token after the callback
    $accessTokenInfo = $client->auth();
    $_SESSION['access_token']   = $accessTokenInfo['access_token'];
    $_SESSION['access_secret']  = $accessTokenInfo['access_secret'];
}
// $accessTokenInfo has the following structure
// array('access_token' => ..., 'access_secret' => ...);
// keeps the access token in a secure place
// if authenticated
if ($_SESSION['access_token']) {
    //var_dump($_SESSION);
    // clean up session data
    unset($_SESSION['request_token']);
    unset($_SESSION['request_secret']);
    // gets info of the authenticated user
    $auth = new \Upwork\API\Routers\Auth($client);
    $info = $auth->getUserInfo();
    
    //$roles = new \Upwork\API\Routers\Hr\Roles($client);
    //$info = $roles->getAll();
    echo "<BR/>PROFILE:<BR/>".print_r($info);
}

<?php

* Template Name: Upwork Template

* Description: A Page Template for displaying Upwork API capability.

session_start();

require WP_UPWORK_PLUGIN_DIR . '/vendor/autoload.php';

$config = new \Upwork\API\Config(

array(

'consumerKey' => get_option('wp_upwork_api_key'), // SETUP YOUR CONSUMER KEY

'consumerSecret' => get_option('wp_upwork_api_secret'), // SETUP YOUR KEY SECRET

'accessToken' => $_SESSION['access_token'], // got access token

'accessSecret' => $_SESSION['access_secret'], // got access secret

'requestToken' => $_SESSION['request_token'], // got request token

'requestSecret' => $_SESSION['request_secret'], // got request secret

'verifier' => $_GET['oauth_verifier'], // got oauth verifier after authorization

'mode' => 'web', // can be 'nonweb' for console apps (default),

// and 'web' for web-based apps

'debug' => true, // enables debug mode. Note that enabling debug in web-based applications can block redirects

'authType' => 'OAuthPHPLib' // your own authentication type, see AuthTypes directory

)

);

$client = new \Upwork\API\Client($config);

//var_dump($_SESSION);exit;

if (empty($_SESSION['request_token']) && empty($_SESSION['access_token'])) {

// we need to get and save the request token. It will be used again

// after the redirect from the Upwork site

$requestTokenInfo = $client->getRequestToken();

$_SESSION['request_token'] = $requestTokenInfo['oauth_token'];

$_SESSION['request_secret'] = $requestTokenInfo['oauth_token_secret'];

// request authorization

$client->auth();

} elseif (empty($_SESSION['access_token'])) {

// the callback request should be pointed to this script as well as

// the request access token after the callback

$accessTokenInfo = $client->auth();

$_SESSION['access_token'] = $accessTokenInfo['access_token'];

$_SESSION['access_secret'] = $accessTokenInfo['access_secret'];

}

// $accessTokenInfo has the following structure

// array('access_token' => ..., 'access_secret' => ...);

// keeps the access token in a secure place

// if authenticated

if ($_SESSION['access_token']) {

//var_dump($_SESSION);

// clean up session data

unset($_SESSION['request_token']);

unset($_SESSION['request_secret']);

// gets info of the authenticated user

$auth = new \Upwork\API\Routers\Auth($client);

$info = $auth->getUserInfo();

//$roles = new \Upwork\API\Routers\Hr\Roles($client);

//$info = $roles->getAll();

echo "<BR/>PROFILE:<BR/>".print_r($info);

}

The template name is ‘Upwork Template’

Then create a new page ‘Upwork’ and select the template ‘Upwork Template’

Okay. One more thing. It’s better to change the permalink of our page url to http://localhost/works/wordpress_local/upwork/ instead of http://localhost/works/wordpress_local/?p=123. To do this, please go to Settings -> Permalinks -> Select ‘Post name’ Then Click ‘Save Changes’. It’d change the page url like above. BUT if you open the link and show 404 error, it means something wrong on your .htaccess or the permission or the apache2 setting. I tried many thing from

teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo chmod 777 .htaccess 
teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo service apache2 restart

1 2	teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo chmod 777 .htaccess teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo service apache2 restart

teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo a2enmod rewrite
Module rewrite already enabled

1 2	teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo a2enmod rewrite Module rewrite already enabled

BUT NOTHING IS WORKING. IT’S FINALLY WORKING IS FROM http://askubuntu.com/questions/48362/how-to-enable-mod-rewrite-in-apache. I need to put ‘AllowOverride All’ in the default apache2 configuration file:

teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo gedit /etc/apache2/sites-available/000-default.conf

1	teddy@teddy-K43SJ:~/Documents/works/wordpress_local$ sudo gedit /etc/apache2/sites-available/000-default.conf

Then add these lines:

<VirtualHost *:80>
	...
	DocumentRoot /var/www/html
	
	<Directory "/var/www/html">
		AllowOverride All
	</Directory>

	...
</VirtualHost>

...

DocumentRoot /var/www/html

AllowOverride All

</Directory>

...

</VirtualHost>

Then restart apache2 server.
Okay. It’s working now. It can open http://localhost/works/wordpress_local/upwork correctly. ALSO DON’T FORGET TO CHANGE AND SAVE Callback URL IN UPWORK API PAGE (https://www.upwork.com/services/api/keys).
SORRY, ONLY ADMIN CAN SHOW THIS!

Modify ‘upwork-template.php’ so we can save the access token and no need to get new token each API call. I tried like this:

<?php
/*
 * Template Name: Upwork Template
 * Description: A Page Template for displaying Upwork API capability.
 */

session_start();
require WP_UPWORK_PLUGIN_DIR . '/vendor/autoload.php';
$access_token=get_option('wp_upwork_access_token');
$access_token_secret=get_option('wp_upwork_access_token_secret');
if($access_token && $access_token_secret){
    $config = new \Upwork\API\Config(
        array(
            'consumerKey'       => get_option('wp_upwork_api_key'),  // SETUP YOUR CONSUMER KEY
            'consumerSecret'    => get_option('wp_upwork_api_secret'),                  // SETUP YOUR KEY SECRET
            'accessToken'       => $access_token,                   // got access token
            'accessSecret'      => $access_token_secret,            // got access secret
            'mode'              => 'web',                           // can be 'nonweb' for console apps (default),
                                                                    // and 'web' for web-based apps
            'debug'             => true, // enables debug mode. Note that enabling debug in web-based applications can block redirects
            'authType'          => 'OAuthPHPLib' // your own authentication type, see AuthTypes directory
        )
    );
    $client = new \Upwork\API\Client($config);
}else{
    $config = new \Upwork\API\Config(
        array(
            'consumerKey'       => get_option('wp_upwork_api_key'),  // SETUP YOUR CONSUMER KEY
            'consumerSecret'    => get_option('wp_upwork_api_secret'),                  // SETUP YOUR KEY SECRET
            'accessToken'       => $_SESSION['access_token'],                   // got access token
            'accessSecret'      => $_SESSION['access_secret'],            // got access secret
            'requestToken'      => $_SESSION['request_token'],      // got request token
            'requestSecret'     => $_SESSION['request_secret'],     // got request secret
            'verifier'          => $_GET['oauth_verifier'],         // got oauth verifier after authorization
            'mode'              => 'web',                           // can be 'nonweb' for console apps (default),
                                                                    // and 'web' for web-based apps
            'debug'             => true, // enables debug mode. Note that enabling debug in web-based applications can block redirects
            'authType'          => 'OAuthPHPLib' // your own authentication type, see AuthTypes directory
        )
    );
    $client = new \Upwork\API\Client($config);
    if (empty($_SESSION['request_token']) && empty($_SESSION['access_token'])) {
        // we need to get and save the request token. It will be used again
        // after the redirect from the Upwork site
        $requestTokenInfo = $client->getRequestToken();
        $_SESSION['request_token']  = $requestTokenInfo['oauth_token'];
        $_SESSION['request_secret'] = $requestTokenInfo['oauth_token_secret'];
        // request authorization
        $client->auth();
    } elseif (empty($_SESSION['access_token'])) {
        // the callback request should be pointed to this script as well as
        // the request access token after the callback
        $accessTokenInfo = $client->auth();
        $_SESSION['access_token']   = $accessTokenInfo['access_token'];
        $_SESSION['access_secret']  = $accessTokenInfo['access_secret'];
        
        update_option('wp_upwork_access_token',$accessTokenInfo['access_token']);
        update_option('wp_upwork_access_token_secret',$accessTokenInfo['access_secret']);
    }
}

// $accessTokenInfo has the following structure
// array('access_token' => ..., 'access_secret' => ...);
// keeps the access token in a secure place
// if authenticated
if ($access_token) {
//if ($_SESSION['access_token']) {
    //var_dump($_SESSION);
    // clean up session data
    unset($_SESSION['request_token']);
    unset($_SESSION['request_secret']);
    // gets info of the authenticated user
    $auth = new \Upwork\API\Routers\Auth($client);
    $info = $auth->getUserInfo();
    
    //$roles = new \Upwork\API\Routers\Hr\Roles($client);
    //$info = $roles->getAll();
    echo "<BR/>PROFILE:<BR/>".print_r($info);
}

<?php

* Template Name: Upwork Template

* Description: A Page Template for displaying Upwork API capability.

session_start();

require WP_UPWORK_PLUGIN_DIR . '/vendor/autoload.php';

$access_token=get_option('wp_upwork_access_token');

$access_token_secret=get_option('wp_upwork_access_token_secret');

if($access_token && $access_token_secret){

$config = new \Upwork\API\Config(

array(

'consumerKey' => get_option('wp_upwork_api_key'), // SETUP YOUR CONSUMER KEY

'consumerSecret' => get_option('wp_upwork_api_secret'), // SETUP YOUR KEY SECRET

'accessToken' => $access_token, // got access token

'accessSecret' => $access_token_secret, // got access secret