CURL is the library account is used to help to make the transfer data through many other protocol (as HTTP, FPT …).

1. How to use CURL in PHP:

A CURL application typically has three basic steps:

Step 1: Initialize CURL: $ch = curl_init().

Step 2: Configure parameters for CURL:

curl_setopt($ch, CURLOPT_URL, "https://soltuts.com");

Curl_setopt(1,2,3) has 3 input parameters:

    1 is a CURL object
    2 is the configuration name
    3 is the value Some common configuration names with CURL:

CURLOPT_URL: path to the URL to be processed

CURLOPT_RETURNTRANSFER: if true, the result will be returned to the curl_exec function, so we have to echo that result to print to the browser, if false, it will print the result to the browser.

CURLOPT_USERAGENT: Used to simulate which browser is sending (user agent)

CURLOPT_TIMEOUT: Set the lifetime of a CURL request

CURLOPT_FILE: Save results to file

CURLOPT_POSTFIELDS: its value is an array of keys => value, corresponding to its name and value in the input tags when submitting the FORM

Step 3: Execute CURL: curl_exec($ch);

Step 4: Break CURL, release data: curl_close($ch);

2. Example:

Post Data Using cURL:

<?php
$url = '{POST_REST_ENDPOINT}';
 
$curl = curl_init();
 
$fields = array(
    'field_name_1' => 'Value 1',
    'field_name_2' => 'Value 2',
    'field_name_3' => 'Value 3'
);
 
$fields_string = http_build_query($fields);
 
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_POST, TRUE);
curl_setopt($curl, CURLOPT_POSTFIELDS, $fields_string);
 
$data = curl_exec($curl);
 
curl_close($curl);

Post JSON Data Using cURL:

<?php
$url = '{POST_REST_ENDPOINT}';
 
$curl = curl_init();
 
$fields = array(
    'field_name_1' => 'Value 1',
    'field_name_2' => 'Value 2',
    'field_name_3' => 'Value 3'
);
 
$json_string = json_encode($fields);
 
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_POST, TRUE);
curl_setopt($curl, CURLOPT_POSTFIELDS, $json_string);
curl_setopt($curl, CURLOPT_HTTPHEADER, array('Content-Type:application/json'));
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true );
 
$data = curl_exec($curl);
 
curl_close($curl);

Upload Files Using cURL:

<?php
$url = '{POST_REST_ENDPOINT}';
 
$curl = curl_init();
 
if (function_exists('curl_file_create')) {
  $fileAttachment = curl_file_create('/absolute/path/to/file/');
} else {
  $fileAttachment = '@' . realpath('/absolute/path/to/file/');
}
 
$fields = array(
    'field_name_1' => 'Value 1',
    'field_name_2' => 'Value 2',
    'field_name_3' => 'Value 3',
    'uploaded_file' => $fileAttachment
);
 
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_POST, TRUE);
curl_setopt($curl, CURLOPT_POSTFIELDS, $fields);
curl_setopt($curl, CURLOPT_RETURNTRANSFER,1);
 
$data = curl_exec($curl);
 
curl_close($curl);