123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143
import type { Drash } from "../../mod.ts";/** * @param request - Contains the instance of the request. * @param server - Contains the instance of the server. * @param response - Contains the instance of the response. */export type MiddlewareFunction =  | ((    request: Drash.Http.Request,    response: Drash.Http.Response,  ) => Promise<void>)  | ((request: Drash.Http.Request, response: Drash.Http.Response) => void);
/** * @description *     before_request?: MiddlewareFunction[] * *         An array that contains all the functions that will be run before a Drash.Http.Request is handled. * *     after_request: MiddlewareFunction[] * *         An array that contains all the functions that will be run after a Drash.Http.Request is handled. * */export type MiddlewareType = {  before_request?: MiddlewareFunction[];  after_request?: MiddlewareFunction[];};
/** * Function associated to decorate the middleware decorators * * @param middlewares - Contains middlewares to be executed */export function Middleware(middlewares: MiddlewareType) {  return function (...args: unknown[]) {    switch (args.length) {      case 1:        // Class decorator        // @ts-ignore        return ClassMiddleware(middlewares).apply(this, args);      case 2:        // Property decorator        break;      case 3:        if (typeof args[2] == "number") {          // Parameter decorator          break;        }        // @ts-ignore        return MethodMiddleware(middlewares).apply(this, args);      default:        throw new Error("Not a valid decorator");    }  };}
/** * Executes the middleware function before or after the request at method level * * @param middlewares - Contains all middleware to be run */function MethodMiddleware(  middlewares: MiddlewareType,): (  target: Drash.Http.Resource,  propertyKey: string,  descriptor: PropertyDescriptor,) => any { // The return type should be `PropertyDescriptor` as that is what is returned, but as we modify `descriptor.value`, the actual returned type is slightly different  return function (    target: Drash.Http.Resource,    propertyKey: string,    descriptor: PropertyDescriptor,  ) {    const originalFunction = descriptor.value;    descriptor.value = async function (...args: unknown[]) { // `args` seems to always be `[]`      const { request, response } = Object.getOwnPropertyDescriptors(this);      // Execute before_request Middleware if exist      if (middlewares.before_request != null) {        for (const middleware of middlewares.before_request) {          await middleware(request.value, response.value);        }      }
      // Execute function      const result = originalFunction.apply(this, args);
      // Execute after_request Middleware if exist      if (middlewares.after_request != null) {        for (const middleware of middlewares.after_request) {          await middleware(request.value, result);        }      }      return result;    };
    return descriptor;  };}
/** * Executes the middleware function before or after the request at class level * * @param middlewares - Contains all middleware to be run */function ClassMiddleware(middlewares: MiddlewareType) {  return function <T extends { new (...args: unknown[]): {} }>(constr: T) { // `args` seems to always be `[]`    const classFunctions = Object.getOwnPropertyDescriptors(constr.prototype);
    for (const key in classFunctions) {      if (key == "constructor") {        continue;      }
      const originalFunction = classFunctions[key].value;      classFunctions[key].value = async function (...args: unknown[]) {        const { request, response } = Object.getOwnPropertyDescriptors(this);        // Execute before_request Middleware if exist        if (middlewares.before_request != null) {          for (const middleware of middlewares.before_request) {            await middleware(request.value, response.value);          }        }
        // Execute function        const result = originalFunction.apply(this, args);
        // Execute after_request Middleware if exist        if (middlewares.after_request != null) {          for (const middleware of middlewares.after_request) {            await middleware(request.value, result);          }        }        return result;      };
      Object.defineProperty(constr.prototype, key, classFunctions[key]);    }
    return constr;  };}