PHP Class for HTTP Response Status Codes

HttpResponse.php

<?php
  /**
   * This Software is provided "as is" under the terms of the MIT license.
   * @link https://opensource.org/licenses/MIT
   */

  /**
   * Provides named constants for HTTP protocol status codes and their messages
   *
   * - Originally written for the Recess Framework http://www.recessframework.com
   * - Forked from https://gist.github.com/ewwink/f14474fd955801153c47
   * - Forked from https://gist.github.com/aryelgois/e577aa73ebbe1463532ab8a584e3d16c
   * - Adapted for general use
   * - Adapted for my use
   *
   * Code beauty upadrian@2023
   *
   * @author Kris Jordan
   * @author Aryel Mota Góis
   * @author upadrian
   * @license MIT
   * @link https://gist.github.com/upadrian/f6f642a86d2f0323ace0f64ab0bc24b0
   * @version 0.1.3
   */
  class Http {
    
    // Informational 1xx
    const HTTP_CONTINUE = 100;
    const HTTP_SWITCHING_PROTOCOLS = 101;
    const HTTP_PROCESSING = 102;
    const HTTP_CHECKPOINT = 103;
    
    // Successful 2xx
    const HTTP_OK = 200;
    const HTTP_CREATED = 201;
    const HTTP_ACCEPTED = 202;
    const HTTP_NONAUTHORITATIVE_INFORMATION = 203;
    const HTTP_NO_CONTENT = 204;
    const HTTP_RESET_CONTENT = 205;
    const HTTP_PARTIAL_CONTENT = 206;
    const HTTP_MULTI_STATUS = 207;
    const HTTP_ALREDY_REPORTED = 208;
    
    // Redirection 3xx
    const HTTP_MULTIPLE_CHOICES = 300;
    const HTTP_MOVED_PERMANENTLY = 301;
    const HTTP_FOUND = 302;
    const HTTP_SEE_OTHER = 303;
    const HTTP_NOT_MODIFIED = 304;
    const HTTP_USE_PROXY = 305;
    const HTTP_UNUSED = 306;
    const HTTP_TEMPORARY_REDIRECT = 307;
    const HTTP_PERMANENT_REDIRECT = 308;
    const ERROR_CODES_START = 400;
    
    // Client Error 4xx
    const HTTP_BAD_REQUEST = 400;
    const HTTP_UNAUTHORIZED = 401;
    const HTTP_PAYMENT_REQUIRED = 402;
    const HTTP_FORBIDDEN = 403;
    const HTTP_NOT_FOUND = 404;
    const HTTP_METHOD_NOT_ALLOWED = 405;
    const HTTP_NOT_ACCEPTABLE = 406;
    const HTTP_PROXY_AUTHENTICATION_REQUIRED = 407;
    const HTTP_REQUEST_TIMEOUT = 408;
    const HTTP_CONFLICT = 409;
    const HTTP_GONE = 410;
    const HTTP_LENGTH_REQUIRED = 411;
    const HTTP_PRECONDITION_FAILED = 412;
    const HTTP_REQUEST_ENTITY_TOO_LARGE = 413;
    const HTTP_REQUEST_URI_TOO_LONG = 414;
    const HTTP_UNSUPPORTED_MEDIA_TYPE = 415;
    const HTTP_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
    const HTTP_EXPECTATION_FAILED = 417;
    const HTTP_I_M_A_TEAPOT = 418;
    const HTTP_UNPROCESSABLE_ENTITY = 422;
    const HTTP_LOCKED = 423;
    const HTTP_FAILED_DEPENDENCY = 424;
    const HTTP_UNASSIGNED = 425;
    const HTTP_UPGRADE_REQUIRED = 426;
    const HTTP_PRECONDITION_REQUIRED = 428;
    const HTTP_TOO_MANY_REQUESTS = 429;
    const HTTP_REQUEST_HEADER_FIELDS_TOO_LARGE = 431;
    const HTTP_UNAVAILABLE_FOR_LEGAL_REASONS = 451;
    // Server Error 5xx
    const HTTP_INTERNAL_SERVER_ERROR = 500;
    const HTTP_NOT_IMPLEMENTED = 501;
    const HTTP_BAD_GATEWAY = 502;
    const HTTP_SERVICE_UNAVAILABLE = 503;
    const HTTP_GATEWAY_TIMEOUT = 504;
    const HTTP_VERSION_NOT_SUPPORTED = 505;
    const HTTP_VARIANT_ALSO_NEGOTIATES = 506;
    const HTTP_INSUFFICIENT_STORAGE = 507;
    const HTTP_LOOP_DETECTED = 508;
    const HTTP_BANDWIDTH_LIMIT_EXCEEDED = 509;
    const HTTP_NOT_EXTENDED = 510;
    const HTTP_NETWORK_AUTHENTICATION_REQUIRED = 511;
    const HTTP_NOT_UPDATED = 512;
    /**
     * Maps status codes to standard messages
     * @var string[]
     */
    protected static array $messages = [
      // Informational 1xx
      100 => 'Continue',
      101 => 'Switching Protocols',
      102 => 'Processing',
      103 => 'Checkpoint',
      // Successful 2xx
      200 => 'OK',
      201 => 'Created',
      202 => 'Accepted',
      203 => 'Non-Authoritative Information',
      204 => 'No Content',
      205 => 'Reset Content',
      206 => 'Partial Content',
      207 => 'Multi-Status (Multi-Status, WebDAV)',
      208 => 'Already Reported (WebDAV)',
      // Redirection 3xx
      300 => 'Multiple Choices',
      301 => 'Moved Permanently',
      302 => 'Found',
      303 => 'See Other',
      304 => 'Not Modified',
      305 => 'Use Proxy',
      306 => '(Unused)',
      307 => 'Temporary Redirect',
      308 => 'Permanent Redirect',
      // Client Error 4xx
      400 => 'Bad Request',
      401 => 'Unauthorized',
      402 => 'Payment Required',
      403 => 'Forbidden',
      404 => 'Not Found',
      405 => 'Method Not Allowed',
      406 => 'Not Acceptable',
      407 => 'Proxy Authentication Required',
      408 => 'Request Timeout',
      409 => 'Conflict',
      410 => 'Gone',
      411 => 'Length Required',
      412 => 'Precondition Failed',
      413 => 'Request Entity Too Large',
      414 => 'Request-URI Too Long',
      415 => 'Unsupported Media Type',
      416 => 'Requested Range Not Satisfiable',
      417 => 'Expectation Failed',
      418 => 'I\'m a teapot',
      422 => 'Unprocessable Entity (WebDAV)',
      423 => 'Locked (WebDAV)',
      424 => 'Failed Dependency (WebDAV)',
      425 => 'Unassigned',
      426 => 'Upgrade Required',
      428 => 'Precondition Required',
      429 => 'Too Many Requests',
      431 => 'Request Header Fields Too Large',
      451 => 'Unavailable for Legal Reasons',
      // Server Error 5xx
      500 => 'Internal Server Error',
      501 => 'Not Implemented',
      502 => 'Bad Gateway',
      503 => 'Service Unavailable',
      504 => 'Gateway Timeout',
      505 => 'HTTP Version Not Supported',
      506 => 'Variant Also Negotiates',
      507 => 'Insufficient Storage (WebDAV)',
      508 => 'Loop Detected (WebDAV)',
      509 => 'Bandwidth Limit Exceeded',
      510 => 'Not Extended',
      511 => 'Network Authentication Required',
      512 => 'Not updated'
    ];

    /**
     * Returns HTTP header message from HTTP code
     * @param integer $code
     * @return string
     * @throws Exception
     */
    public static function getStatusCodeHeader(int $code): string {
      if (!self::checkStatusCode($code)) {
        throw new Exception("Http Status Code is invalid.");
      }
      return "HTTP/1.1 {$code} " . self::$messages[$code];
    }

    /**
     * Send header to the browser
     * @param integer $code HTTP status code
     * @throws Exception
     */
    public static function sendStatusCodeHeader(int $code) {
      if (headers_sent()) {
        throw new Exception("Headers or output already sent.");
      }
      header(self::getStatusCodeHeader($code));
    }

    /**
     * Tells if a status code is a error code
     * @param integer $code HTTP status code
     * @return boolean
     * @throws Exception
     */
    public static function isError(int $code): bool {
      if (!self::checkStatusCode($code)) {
        throw new Exception("Http Status Code is invalid.");
      }
      return $code >= self::ERROR_CODES_START;
    }

    /**
     * Checks if a HTTP response with given status code can have body
     * True if not in 100s and not 204 NO CONTENT and not 304 NOT MODIFIED
     * @param integer $code HTTP status code
     * @return boolean
     * @throws Exception
     */
    public static function statusCodeCanHaveBody(int $code): bool {
      if (!self::checkStatusCode($code)) {
        throw new Exception("Http Status Code is invalid.");
      }
      return ($code < self::HTTP_CONTINUE || $code >= self::HTTP_OK)
        && $code != self::HTTP_NO_CONTENT
        && $code != self::HTTP_NOT_MODIFIED;
    }

    /**
     * Send location header
     * @param string $location
     * @throws Exception
     * @throws Exception
     */
    public static function sendLocationHeader(string $location) {
      if (headers_sent()) {
        throw new Exception("Headers or output already sent.");
      }
      header("Location: {$location}");
    }

    /**
     * Return true if status code is valid and exists
     * @param integer $code
     * @return bool
     */
    private static function checkStatusCode(int $code): bool {
      return isset(self::$messages[$code]);
    }
  }