Status Code Constants

/**
 * Enumerated HTTP status code constants
 * Contains all standard status codes from multiple RFCs
 */
enum StatusCodes {
  // 1xx Informational Responses
  /** Continue - client should continue with request */
  CONTINUE = 100,
  /** Switching Protocols - server switching to different protocol */
  SWITCHING_PROTOCOLS = 101,
  /** Processing - server has received and is processing request */
  PROCESSING = 102,
  /** Early Hints - server likely to send final response with included headers */
  EARLY_HINTS = 103,

  // 2xx Success
  /** OK - request has succeeded */
  OK = 200,
  /** Created - request succeeded and new resource created */
  CREATED = 201,
  /** Accepted - request received but not yet acted upon */
  ACCEPTED = 202,
  /** Non-Authoritative Information - meta-information not from origin server */
  NON_AUTHORITATIVE_INFORMATION = 203,
  /** No Content - no content to send but headers may be useful */
  NO_CONTENT = 204,
  /** Reset Content - tells user agent to reset document view */
  RESET_CONTENT = 205,
  /** Partial Content - response to range header for partial download */
  PARTIAL_CONTENT = 206,
  /** Multi-Status - conveys information about multiple resources */
  MULTI_STATUS = 207,

  // 3xx Redirection
  /** Multiple Choices - request has more than one possible response */
  MULTIPLE_CHOICES = 300,
  /** Moved Permanently - URI of requested resource changed permanently */
  MOVED_PERMANENTLY = 301,
  /** Moved Temporarily - URI changed temporarily */
  MOVED_TEMPORARILY = 302,
  /** See Other - direct client to get resource with GET request */
  SEE_OTHER = 303,
  /** Not Modified - response has not been modified (caching) */
  NOT_MODIFIED = 304,
  /** Use Proxy - must be accessed by proxy (deprecated) */
  USE_PROXY = 305,
  /** Temporary Redirect - resource moved temporarily, same method required */
  TEMPORARY_REDIRECT = 307,
  /** Permanent Redirect - resource moved permanently, same method required */
  PERMANENT_REDIRECT = 308,

  // 4xx Client Errors
  /** Bad Request - server cannot understand request due to invalid syntax */
  BAD_REQUEST = 400,
  /** Unauthorized - client must authenticate to get requested response */
  UNAUTHORIZED = 401,
  /** Payment Required - reserved for future use */
  PAYMENT_REQUIRED = 402,
  /** Forbidden - client does not have access rights to content */
  FORBIDDEN = 403,
  /** Not Found - server cannot find requested resource */
  NOT_FOUND = 404,
  /** Method Not Allowed - request method disabled and cannot be used */
  METHOD_NOT_ALLOWED = 405,
  /** Not Acceptable - no content following user agent criteria */
  NOT_ACCEPTABLE = 406,
  /** Proxy Authentication Required - authentication needed by proxy */
  PROXY_AUTHENTICATION_REQUIRED = 407,
  /** Request Timeout - server would like to shut down unused connection */
  REQUEST_TIMEOUT = 408,
  /** Conflict - request conflicts with current server state */
  CONFLICT = 409,
  /** Gone - requested content permanently deleted from server */
  GONE = 410,
  /** Length Required - Content-Length header field required */
  LENGTH_REQUIRED = 411,
  /** Precondition Failed - client indicated preconditions not met */
  PRECONDITION_FAILED = 412,
  /** Request Entity Too Large - request entity larger than server limits */
  REQUEST_TOO_LONG = 413,
  /** Request-URI Too Long - URI longer than server willing to interpret */
  REQUEST_URI_TOO_LONG = 414,
  /** Unsupported Media Type - media format of requested data not supported */
  UNSUPPORTED_MEDIA_TYPE = 415,
  /** Requested Range Not Satisfiable - range in Range header cannot be fulfilled */
  REQUESTED_RANGE_NOT_SATISFIABLE = 416,
  /** Expectation Failed - expectation in Expect header cannot be met */
  EXPECTATION_FAILED = 417,
  /** I'm a teapot - attempt to brew coffee with a teapot */
  IM_A_TEAPOT = 418,
  /** Insufficient Space on Resource - insufficient storage to complete request */
  INSUFFICIENT_SPACE_ON_RESOURCE = 419,
  /** Method Failure - method failed (deprecated Spring Framework response) */
  METHOD_FAILURE = 420,
  /** Misdirected Request - server cannot produce response for scheme/authority combination */
  MISDIRECTED_REQUEST = 421,
  /** Unprocessable Entity - request well-formed but unable to follow due to semantic errors */
  UNPROCESSABLE_ENTITY = 422,
  /** Locked - resource being accessed is locked */
  LOCKED = 423,
  /** Failed Dependency - request failed due to failure of previous request */
  FAILED_DEPENDENCY = 424,
  /** Upgrade Required - server refuses current protocol but may accept after upgrade */
  UPGRADE_REQUIRED = 426,
  /** Precondition Required - origin server requires request to be conditional */
  PRECONDITION_REQUIRED = 428,
  /** Too Many Requests - user sent too many requests in given time */
  TOO_MANY_REQUESTS = 429,
  /** Request Header Fields Too Large - server unwilling to process due to large header fields */
  REQUEST_HEADER_FIELDS_TOO_LARGE = 431,
  /** Unavailable For Legal Reasons - resource cannot legally be provided */
  UNAVAILABLE_FOR_LEGAL_REASONS = 451,

  // 5xx Server Errors
  /** Internal Server Error - server encountered unexpected condition */
  INTERNAL_SERVER_ERROR = 500,
  /** Not Implemented - request method not supported by server */
  NOT_IMPLEMENTED = 501,
  /** Bad Gateway - server got invalid response while acting as gateway */
  BAD_GATEWAY = 502,
  /** Service Unavailable - server not ready to handle request */
  SERVICE_UNAVAILABLE = 503,
  /** Gateway Timeout - server acting as gateway cannot get response in time */
  GATEWAY_TIMEOUT = 504,
  /** HTTP Version Not Supported - HTTP version in request not supported */
  HTTP_VERSION_NOT_SUPPORTED = 505,
  /** Insufficient Storage - server unable to store representation needed */
  INSUFFICIENT_STORAGE = 507,
  /** Network Authentication Required - client needs to authenticate to gain network access */
  NETWORK_AUTHENTICATION_REQUIRED = 511
}

import { StatusCodes } from "http-status-codes";

// Express.js response
app.get("/users", (req, res) => {
  res.status(StatusCodes.OK).json(users);
});

// Error handling
if (user === null) {
  return res.status(StatusCodes.NOT_FOUND).json({
    error: "User not found"
  });
}

// Conditional logic based on status codes
switch (response.status) {
  case StatusCodes.OK:
    return response.data;
  case StatusCodes.NOT_FOUND:
    throw new Error("Resource not found");
  case StatusCodes.INTERNAL_SERVER_ERROR:
    throw new Error("Server error");
}

// Type-safe status code checking
const isSuccessStatus = (status: number): boolean => {
  return status >= StatusCodes.OK && status < StatusCodes.MULTIPLE_CHOICES;
};