(PHP Extension) curl with Variable Substitution in a GraphQL Request Body

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

Note: This example requires Chilkat v11.5.0 or greater.

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<?php

include("chilkat.php");

$success = false;

$success = false;

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

// curl -X POST https://api.example.com/graphql \
//   -H "Content-Type: application/graphql; charset=utf-8" \
//   -H "Accept: application/json" \
//   --data-binary "mutation {
//   createUser(
//     input: {
//       name: \"{{name}}\"
//       city: \"{{city}}\"
//       note: \"{{note}}\"
//       bio: \"{{bio}}\"
//     }
//   ) {
//     id
//     name
//   }
// }"

// Build the above curl command.
$sbCurl = new CkStringBuilder();
$sbCurl->AppendLn('curl -X POST https://api.example.com/graphql \\');
$sbCurl->AppendLn('  -H \'Content-Type: application/graphql; charset=utf-8\' \\');
$sbCurl->AppendLn('  -H \'Accept: application/json\' \\');
$sbCurl->AppendLn('  -d \'mutation {');
$sbCurl->AppendLn('  createUser(');
$sbCurl->AppendLn('    input: {');
$sbCurl->AppendLn('      name: \\\'{{name}}\\\'');
$sbCurl->AppendLn('      city: \\\'{{city}}\\\'');
$sbCurl->AppendLn('      note: \\\'{{note}}\\\'');
$sbCurl->AppendLn('      bio: \\\'{{bio}}\\\'');
$sbCurl->AppendLn('    }');
$sbCurl->AppendLn('  ) {');
$sbCurl->AppendLn('    id');
$sbCurl->AppendLn('    name');
$sbCurl->AppendLn('  }');
$sbCurl->AppendLn('}\'');

$curl = new CkHttpCurl();

// Provide values for variables
$curl->SetVar('name','José O'Connor');
$curl->SetVar('city','München');
$curl->SetVar('note','He said \'Hello, world!\' — and left…');
$curl->SetVar('bio','Loves sushi, café visits, and π ≈ 3.14159');

// 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 the quote chars around "Hello, world!" are properly escaped.

// POST /graphql HTTP/1.1
// Accept: application/json
// Host: api.example.com
// Content-Type: application/graphql; charset=utf-8
// Content-Length: 250
// 
// mutation {
//   createUser(
//     input: {
//       name: "José O'Connor"
//       city: "München"
//       note: "He said \"Hello, world!\" — and left…"
//       bio: "Loves sushi, café visits, and π ≈ 3.14159"
//     }
//   ) {
//     id
//     name
//   }
// }

?>