pablo-rest-api-standard/src/index.ts

import { Request, Response } from "express";

interface PRASResponse extends Response {
  pras: {
    ok: (message: string, data: any, code: string, extra: any) => void;
    created: (message: string, data: any, code: string, extra: any) => void;
    badRequest: (message: string, data: any, code: string, extra: any) => void;
    unauthorized: (
      message: string,
      data: any,
      code: string,
      extra: any
    ) => void;
    forbidden: (message: string, data: any, code: string, extra: any) => void;
    notFound: (message: string, data: any, code: string, extra: any) => void;
    serverError: (message: string, data: any, code: string, extra: any) => void;
    customMessage: (
      statusCode: number,
      message: string,
      data: any,
      code: string,
      extra: any
    ) => void;
  };
}

export class PRAS {
  private getPRASResultObject(
    status: string,
    message: string,
    data: any,
    code: string,
    extra: any
  ) {
    return {
      status: status || "OK",
      message: message || "",
      data: data || null,
      code: code || "UNKNOWN_CODE",
      extra: extra || null,
    };
  }

  public responseMiddleware() {
    return (req: Request, res: PRASResponse, next: Function): void => {
      res.pras = {
        ok: (message, data, code, extra) => {
          res
            .status(200)
            .json(this.getPRASResultObject("OK", message, data, code, extra));
        },
        created: (message, data, code, extra) => {
          res
            .status(201)
            .json(this.getPRASResultObject("OK", message, data, code, extra));
        },
        badRequest: (message, data, code, extra) => {
          res
            .status(400)
            .json(this.getPRASResultObject("FAIL", message, data, code, extra));
        },
        unauthorized: (message, data, code, extra) => {
          res
            .status(401)
            .json(this.getPRASResultObject("FAIL", message, data, code, extra));
        },
        forbidden: (message, data, code, extra) => {
          res
            .status(403)
            .json(this.getPRASResultObject("FAIL", message, data, code, extra));
        },
        notFound: (message, data, code, extra) => {
          res
            .status(404)
            .json(this.getPRASResultObject("FAIL", message, data, code, extra));
        },
        serverError: (message, data, code, extra) => {
          res
            .status(500)
            .json(
              this.getPRASResultObject("ERROR", message, data, code, extra)
            );
        },
        customMessage: (statusCode, message, data, code, extra) => {
          let status;
          if (statusCode >= 500) {
            status = "ERROR";
          } else if (statusCode >= 400) {
            status = "FAIL";
          } else {
            status = "OK";
          }
          res
            .status(statusCode)
            .json(this.getPRASResultObject(status, message, data, code, extra));
        },
      };

      next();
    };
  }
}

export default new PRAS();