PHP Extension Requires Chilkat v11.5.0+

curl with Variable Substitution in a JSON Request Body

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This example shows how to use variables inside a JSON request body using the {{variable_name}} syntax. When the HTTP request’s Content-Type indicates JSON, Chilkat automatically applies proper JSON escaping to each substituted value, ensuring the resulting JSON remains valid. PHP Extension

<?php

include("chilkat.php");

$success = false;

//  Variable names are enclosed between {{ and }}
//  Important: The variable {{var_name}} should be placed inside the quotes.

//  This is correct:
//  curl -X POST https://api.example.com/messages \
//    -H "Content-Type: application/json" \
//    -d '{"text":"{{message}}"}'

//  This is incorrect:
//    -d '{"text":{{message}}}'

$sbCurl = new CkStringBuilder();
$sbCurl->AppendLn('curl -X POST https://api.example.com/messages \\');
$sbCurl->AppendLn('  -H \'Content-Type: application/json\' \\');
$sbCurl->AppendLn('  -d '{\'text\':\'{{message}}\'}'');

$curl = new CkHttpCurl();

//  In this example, the value we'll provide for the "message" variable
//  will contain chars that require JSON escaping.
$curl->SetVar('message','He said \'Hello, world!\'');

//  To demonstrate how the variables are replaced, this example does not execute the curl command. 
//  Instead, it generates the raw HTTP request that would be sent if the curl command were run.
$sbRawRequest = new CkStringBuilder();
$success = $curl->ToRawRequest($sbCurl->getAsString(),$sbRawRequest);
if ($success == false) {
    print $curl->lastErrorText() . "\n";
    exit;
}

print $sbRawRequest->getAsString() . "\n";

//  The output is shown below.
//  Notice that the quote chars around "Hello World!" are properly JSON escaped.

//  POST /messages HTTP/1.1
//  Host: api.example.com
//  Content-Type: application/json
//  Content-Length: 36
//  
//  {"text":"He said \"Hello, world!\""}

?>