Edits history of script submission #22277 for ' Lightweight Http Router Module (http)'

• deno

  Edit in Windmill

  Embed

  /**
   * Supported HTTP methods for routing.
   */
  export enum METHOD {
    GET = "GET",
    POST = "POST",
    PUT = "PUT",
    PATCH = "PATCH",
    DELETE = "DELETE",
  }
  
  /**
   * The standard request object passed to route handlers.
   * Contains parsed URL components, headers, and body.
   */
  type HttpRequest = {
    /** HTTP method (e.g., "GET", "POST") */
    method: string;
    /** The matched route pattern (e.g., "/users/:id") */
    route: string;
    /** The full URL path */
    path: string;
    /** Extracted path parameters (e.g., { id: "123" }) */
    params: Record<string, string>;
    /** Query string parameters (e.g., { sort: "asc" }) */
    query: Record<string, string>;
    /** Request headers */
    headers: Record<string, string>;
    /** Parsed request body */
    body: any;
    /** Raw request string (if applicable) */
    raw_string: string | null;
  };
  
  /**
   * Windmill HTTP event object, extending HttpRequest with trigger metadata.
   */
  type HttpEvent = HttpRequest & {
    /** Always "http" for HTTP triggers */
    kind: "http";
    /** The path used to trigger the script */
    trigger_path: string;
  };
  
  /**
   * A lightweight, chainable router for Windmill HTTP scripts.
   * Supports method chaining, custom error handling, and automatic response formatting.
   */
  export class Router {
    private routes: Record<string, Record<string, (req: HttpRequest) => any>> = {};
  
    /**
     * Preprocessor hook for Windmill.
     * Validates the event kind and prepares the request object.
     * @param event - The incoming Windmill event
     * @returns An object containing the normalized request
     */
    preprocessor = async function (event: HttpEvent) {
      if (event.kind === "http") {
        return { req: event };
      }
      throw new Error(`Unsupported trigger kind: ${event.kind}`);
    };
  
    /**
     * Normalizes HTTP method strings to uppercase for consistent routing.
     */
    private normalizeMethod(method: string): string {
      return method.toUpperCase();
    }
  
    /**
     * Registers a GET route.
     * @param route - The URL path pattern (e.g., "/users")
     * @param handler - The function to execute when the route is matched
     */
    get(route: string, handler: (req: HttpRequest) => any) {
      return this.addRoute(METHOD.GET, route, handler);
    }
  
    /**
     * Registers a POST route.
     * @param route - The URL path pattern
     * @param handler - The function to execute
     */
    post(route: string, handler: (req: HttpRequest) => any) {
      return this.addRoute(METHOD.POST, route, handler);
    }
  
    /**
     * Registers a PUT route.
     * @param route - The URL path pattern
     * @param handler - The function to execute
     */
    put(route: string, handler: (req: HttpRequest) => any) {
      return this.addRoute(METHOD.PUT, route, handler);
    }
  
    /**
     * Registers a PATCH route.
     * @param route - The URL path pattern
     * @param handler - The function to execute
     */
    patch(route: string, handler: (req: HttpRequest) => any) {
      return this.addRoute(METHOD.PATCH, route, handler);
    }
  
    /**
     * Registers a DELETE route.
     * @param route - The URL path pattern
     * @param handler - The function to execute
     */
    delete(route: string, handler: (req: HttpRequest) => any) {
      return this.addRoute(METHOD.DELETE, route, handler);
    }
  
    /**
     * Internal method to register a route.
     * @param method - The HTTP method
     * @param route - The path pattern
     * @param handler - The handler function
     * @returns The Router instance for chaining
     */
    private addRoute(method: METHOD, route: string, handler: (req: HttpRequest) => any) {
      if (!this.routes[method]) {
        this.routes[method] = {};
      }
      this.routes[method][route] = handler;
      return this;
    }
  
    /**
     * Executes the matched handler or throws an appropriate HttpError.
     * @param req - The request object
     * @returns The handler's return value
     * @throws HttpError if route or method is not found
     */
    private executeHandler(req: HttpRequest): any {
      const method = this.normalizeMethod(req.method);
      const route = req.route;
  
      if (!this.routes[method]) {
        throw HttpError.MethodNotAllowed(`Method ${method} not allowed`);
      }
  
      const handler = this.routes[method][route];
  
      if (!handler) {
        throw HttpError.NotFound(`Route ${route} not found`);
      }
  
      return handler(req);
    }
  
    /**
     * Main entry point for handling requests.
     * Wraps execution in try-catch to standardize error responses.
     * @param req - The request object
     * @returns A formatted WindmillResponse object
     */
    handle(req: HttpRequest): any {
      try {
        return this.executeHandler(req);
      } catch (error) {
        console.error("Router Error:", error);
  
        if (!(error instanceof HttpError)) {
          // Wrap unexpected errors in a 500 HttpError
          throw HttpError.InternalError(undefined, error);
        }
  
        // Format HttpError for Windmill
        return {
          windmill_status_code: error.status,
          result: {
            statusCode: error.status,
            error: error.message
          }
        };
      }
    }
  }
  
  /**
   * Custom error class for HTTP status codes.
   * Extends the native Error class with a status code and optional cause.
   */
  export class HttpError extends Error {
    status: number;
  
    /**
     * Creates a new HttpError.
     * @param status - HTTP status code (e.g., 404, 500)
     * @param message - Error message
     * @param cause - The original error that caused this one (preserves stack trace)
     */
    constructor(status: number, message: string, cause?: any) {
      super(message);
      this.status = status;
      this.name = 'HttpError';
      // Manual assignment for runtime compatibility in serverless environments
      if (cause) {
        (this as any).cause = cause;
      }
    }
  
    static BadRequest(message = 'Bad Request', cause?: any) {
      return new HttpError(400, message, cause);
    }
  
    static Unauthorized(message = 'Unauthorized', cause?: any) {
      return new HttpError(401, message, cause);
    }
  
    static Forbidden(message = 'Forbidden', cause?: any) {
      return new HttpError(403, message, cause);
    }
  
    static NotFound(message = 'Not found', cause?: any) {
      return new HttpError(404, message, cause);
    }
  
    static MethodNotAllowed(message = 'Method not allowed', cause?: any) {
      return new HttpError(405, message, cause);
    }
  
    static UnprocessableContent(message = 'Unprocessable Content', cause?: any) {
      return new HttpError(422, message, cause);
    }
  
    static InternalError(message = 'Internal server error', cause?: any) {
      return new HttpError(500, message, cause);
    }
  }
  
  /**
   * Standard Windmill HTTP response structure.
   */
  type WindmillResponse = {
    windmill_status_code: number;
    windmill_headers?: Record<string, string>;
    result: any;
  };
  
  /**
   * Helper class to construct HTTP responses with convenient status codes.
   * Automatically formats output for Windmill.
   */
  export class HttpResponse {
    public status: number;
    public data: any;
    public headers?: Record<string, string>;
  
    constructor(data: any, status: number = 200, headers?: Record<string, string>) {
      this.data = data;
      this.status = status;
      this.headers = headers;
    }
  
    /**
     * Returns a 200 OK response.
     */
    static Ok(data: any, headers?: Record<string, string>) {
      return new HttpResponse(data, 200, headers).toWindmillResponse();
    }
  
    /**
     * Returns a 201 Created response.
     */
    static Created(data: any, headers?: Record<string, string>) {
      return new HttpResponse(data, 201, headers).toWindmillResponse();
    }
  
    /**
     * Returns a 202 Accepted response.
     */
    static Accepted(data: any, headers?: Record<string, string>) {
      return new HttpResponse(data, 202, headers).toWindmillResponse();
    }
  
    /**
     * Returns a 204 No Content response.
     */
    static NoContent(headers?: Record<string, string>) {
      return new HttpResponse(null, 204, headers).toWindmillResponse();
    }
  
    private toWindmillResponse(): WindmillResponse {
      return {
        windmill_status_code: this.status,
        windmill_headers: this.headers,
        result: this.data
      };
    }
  }
  
  // --- Usage Example ---
  
  const router = new Router();
  
  router
    .get("router-test", (req) => {
      return HttpResponse.Ok({ message: "GET TEST" });
    })
    .post("router-test", (req) => {
      if (true) {
        throw HttpError.Forbidden();
      }
  
      return HttpResponse.NoContent();
    });
  
  // # REQUEST MIDDLEWARE
  export async function preprocessor(event: HttpEvent) {
    return await router.preprocessor(event);
  }
  
  // # MAIN ENTRY POINT
  export async function main(req: HttpRequest) {
    return router.handle(req);
  }

  Submitted by as900 60 days ago