Http Status Code

const HTTP_CONTINUE = 100;
const HTTP_SWITCHING_PROTOCOLS = 101;
const HTTP_PROCESSING = 102;            // RFC2518
const HTTP_EARLY_HINTS = 103;           // RFC8297

const HTTP_OK = 200;
const HTTP_CREATED = 201;
const HTTP_ACCEPTED = 202;
const HTTP_NON_AUTHORITATIVE_INFORMATION = 203;
const HTTP_NO_CONTENT = 204;
const HTTP_RESET_CONTENT = 205;
const HTTP_PARTIAL_CONTENT = 206;
const HTTP_MULTI_STATUS = 207;          // RFC4918
const HTTP_ALREADY_REPORTED = 208;      // RFC5842
const HTTP_IM_USED = 226;               // RFC3229

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_RESERVED = 306;
const HTTP_TEMPORARY_REDIRECT = 307;
const HTTP_PERMANENTLY_REDIRECT = 308;  // RFC7238

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_AM_A_TEAPOT = 418;                        // RFC2324
const HTTP_MISDIRECTED_REQUEST = 421;                  // RFC7540
const HTTP_UNPROCESSABLE_ENTITY = 422;                 // RFC4918
const HTTP_LOCKED = 423;                               // RFC4918
const HTTP_FAILED_DEPENDENCY = 424;                    // RFC4918
const HTTP_TOO_EARLY = 425;                            // RFC-ietf-httpbis-replay-04
const HTTP_UPGRADE_REQUIRED = 426;                     // RFC2817
const HTTP_PRECONDITION_REQUIRED = 428;                // RFC6585
const HTTP_TOO_MANY_REQUESTS = 429;                    // RFC6585
const HTTP_REQUEST_HEADER_FIELDS_TOO_LARGE = 431;      // RFC6585
const HTTP_UNAVAILABLE_FOR_LEGAL_REASONS = 451;        // RFC7725

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_EXPERIMENTAL = 506; // RFC2295
const HTTP_INSUFFICIENT_STORAGE = 507;                 // RFC4918
const HTTP_LOOP_DETECTED = 508;                        // RFC5842
const HTTP_NOT_EXTENDED = 510;                         // RFC2774
const HTTP_NETWORK_AUTHENTICATION_REQUIRED = 511;      // RFC6585