purge.php

<?php
/**
 * This file is executed from Nginx using fastcgi.
 *
 * The file must be compatible with PHP 5.4 and later.
 *
 * See also jquery::wp::jquery in jquery/infrastructure [private].
 *
 * Test Plan:
 *
 *     $ REQUEST_URI="/example" php purge.php
 */

$configFile = __DIR__ . '/config.json';

if ( !isset( $_SERVER[ 'REQUEST_URI' ] )
	|| !is_readable( $configFile )
	|| !function_exists( 'curl_init' )
) {
	http_response_code( 500 );
	echo "Context error.\n";
	exit;
}

$config = json_decode( file_get_contents( $configFile ) );
$hwConfig = $config->highwinds;
if ( !$hwConfig
	|| !$hwConfig->api_url
	|| !$hwConfig->api_token
	|| !$hwConfig->account_hash
	|| !$hwConfig->file_hostname
) {
	http_response_code( 500 );
	echo "Configuration error.\n";
	exit;
}

// The StrikeTracker Purge API is protocol-sensitive.
// HTTP and HTTPS need to be purged separately, or
// we can use a protocol-relative file url, which Highwinds
// supports as short-cut for purging both.
$file = "//{$hwConfig->file_hostname}/" . ltrim( $_SERVER[ 'REQUEST_URI' ], '/' );

/**
 * Make an HTTP POST request, submitting JSON data, and receiving JSON data.
 *
 * @param string $url
 * @param array $headers
 * @param array $postData Data to be serialised using JSON as post body
 * @return array|false HTTP response body decoded as JSON, or boolean false
 */
function jq_request_post_json( $url, array $headers, array $postData ) {
	$ch = curl_init( $url );
	curl_setopt_array( $ch, array(
		CURLOPT_HTTPHEADER => $headers,
		CURLOPT_POSTFIELDS =>  json_encode( $postData ),
		CURLOPT_RETURNTRANSFER => true,
	) );
	$response = curl_exec( $ch );
	curl_close( $ch );
	return $response ? json_decode( $response ) : false;
}

header( 'Content-Type: text/plain' );
header( 'X-Content-Type-Options: nosniff' );
echo "Attempting to purge:\n{$file}\n\n";

$result = jq_request_post_json(
	// url
	"{$hwConfig->api_url}/api/accounts/{$hwConfig->account_hash}/purge",
	// headers
	array(
		"Authorization: Bearer {$hwConfig->api_token}",
		"Content-Type: application/json",
	),
	// post body (will be encoded as JSON)
	array(
		'list' => array(
			array( 'url' => $file, 'purgeAllDynamic' => true ),
		),
	)
);

// Successful responses contain an 'id' that identifies the purge.
// Errors should contain an 'error' string and 'code' number.
if ( !$result || !isset( $result->id ) || isset( $result->error ) || isset( $result->code ) ) {
	echo "Purge may have failed.\n\n";
	if ( isset( $result->code ) ) {
		echo "Error code: " . $result->code . "\n";
	}
	if ( isset( $result->error ) ) {
		echo "Error message: " . $result->error . "\n";
	}
} else {
	echo "Done!\n";
}