import { Compiler } from "./compiler.ts";import { Context } from "./context.ts";import { Handler, HTMLRewriter, Server, toFileUrl } from "./deps.ts";import { Router } from "./router.ts";import { ApplicationOptions, Middleware, Mode, Register, RequestHandler, ResponseTransformer,} from "../types.ts";import { ApplicationEvents, ListeningEvent } from "./events.ts";
export class Application extends ApplicationEvents { #server: Server | undefined; #router: Router<this>; #middleware: Middleware<this>[] = []; #requestMiddleware: Middleware<this>[] = []; #responseTransformers: ResponseTransformer[] = []; #process?: Promise<void>;
readonly rootUrl: URL; readonly compiler: Compiler; readonly mode: Mode;
constructor(options: ApplicationOptions) { super();
const { rootUrl, mode } = options;
this.#router = new Router(); this.rootUrl = typeof rootUrl === "string" ? toFileUrl(rootUrl) : rootUrl; this.mode = mode;
this.compiler = new Compiler({ mode, }); }
start(listenOptions: Deno.ListenOptions): void { this.dispatchEvent(new ListeningEvent(listenOptions)); this.#process = this.#start(Deno.listen(listenOptions)); }
async close(): Promise<void> { if (this.#server) { this.#server.close(); } await this.#process; }
async #start(listener: Deno.Listener): Promise<void> { const handler: Handler = (request) => { const context = new Context({ app: this, request, });
let requestHandler: RequestHandler<this>;
if (this.#requestMiddleware.length === 0) { requestHandler = this.#router.find(request.method, context); requestHandler = this.#applyMiddleware( requestHandler, ...this.#middleware, ); } else { requestHandler = (context) => { requestHandler = this.#router.find(request.method, context); requestHandler = this.#applyMiddleware( requestHandler, ...this.#middleware, ); return requestHandler(context); }; requestHandler = this.#applyMiddleware( requestHandler, ...this.#requestMiddleware, ); }
return this.#transformResult(context, requestHandler).then(() => context.response ); };
const server = this.#server = new Server({ handler, onError: this.#handleError, });
await server.serve(listener); }
#handleError(error: unknown) { console.error(error); return new Response("Internal server error", { status: 500 }); }
#applyMiddleware = ( handler: RequestHandler<this>, ...middleware: Middleware<this>[] ): RequestHandler<this> => { for (let i = middleware.length - 1; i >= 0; --i) { handler = middleware[i](handler); }
return handler; };
before(...middlewares: Middleware<this>[]): this { this.#requestMiddleware.push(...middlewares); return this; }
use(...middlewares: Middleware<this>[]): this { this.#middleware.push(...middlewares); return this; }
connect( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("CONNECT", path, requestHandler, ...middleware); }
delete( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("DELETE", path, requestHandler, ...middleware); }
get( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("GET", path, requestHandler, ...middleware); }
head( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("HEAD", path, requestHandler, ...middleware); }
options( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("OPTIONS", path, requestHandler, ...middleware); }
patch( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("PATCH", path, requestHandler, ...middleware); }
post( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("POST", path, requestHandler, ...middleware); }
put( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("PUT", path, requestHandler, ...middleware); }
trace( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { return this.add("TRACE", path, requestHandler, ...middleware); }
any( path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { const methods = [ "CONNECT", "DELETE", "GET", "HEAD", "OPTIONS", "PATCH", "POST", "PUT", "TRACE", ];
return this.match(methods, path, requestHandler, ...middleware); }
match( methods: string[], path: string, requestHandler: RequestHandler<this>, ...middleware: Middleware<this>[] ): Application { for (const method of methods) { this.add(method, path, requestHandler, ...middleware); } return this; }
add( method: string, path: string, requestHandler: RequestHandler<this>, ...middlewares: Middleware<this>[] ): Application { this.#router.add( method, path, (context: Context<this>): Promise<unknown> | unknown => { let routeHandler = requestHandler; for (const middleware of middlewares) { routeHandler = middleware(routeHandler); } return routeHandler(context); }, );
return this; }
register: Register<Application> = (plugin, options) => { const promise = plugin(this, options || {} as any);
if (promise) { promise.then(() => ({})); }
return this; };
addResponseTransformer(responseTransformer: ResponseTransformer) { this.#responseTransformers.push(responseTransformer); }
async #applyResponseTransformers( response: Response, context: Context<this>, ...responseTransformers: ResponseTransformer[] ): Promise<Response> { const rewriter = new HTMLRewriter();
for (let i = responseTransformers.length - 1; i >= 0; --i) { await responseTransformers[i](response, context, rewriter); }
response = rewriter.transform(response);
return response; }
async #transformResult( context: Context<this>, requestHandler: RequestHandler<this>, ): Promise<void> { const result = await requestHandler(context);
if (result instanceof Response) { context.response = await this.#applyResponseTransformers( result, context, ...this.#responseTransformers.reverse(), ); } }}