Separate interface and implementation (#13)

* Separate interface and implementation for objects

* Remove extra line

mod.ts

@@ -1,10 +1,6 @@
 // Copyright 2021 Riki Singh Khorana. All rights reserved. MIT license.
 
-export { Kyuko } from "./kyuko.ts";
-export type {
-  KyukoMiddleware,
-  KyukoRequest,
-  KyukoRequestHandler,
-} from "./kyuko.ts";
-
-export { KyukoResponse } from "./KyukoResponse.ts";
+export { Kyuko } from "./src/Kyuko.ts";
+export type { KyukoMiddleware, KyukoRequestHandler } from "./src/Kyuko.ts";
+export type { KyukoRequest } from "./src/KyukoRequest.ts";
+export type { KyukoResponse } from "./src/KyukoResponse.ts";

kyuko.ts → src/Kyuko.ts

@@ -2,7 +2,8 @@
 
 /// <reference path='./deploy.d.ts' />
 
-import { KyukoResponse } from "./KyukoResponse.ts";
+import { KyukoRequest, KyukoRequestImpl } from "./KyukoRequest.ts";
+import { KyukoResponse, KyukoResponseImpl } from "./KyukoResponse.ts";
 import { RoutePathHandler } from "./RoutePathHandler.ts";
 
 /**
@@ -19,32 +20,13 @@ export type KyukoRequestHandler = (
  * and return early by calling `res.send()` when needed.
  * Hands over execution to the next middleware / request handler on return.
  *
- * Notice how a `next()` call is unneeded.
+ * Notice how a `next()` call is unneeded unlike middleware functions in Express.
  */
 export type KyukoMiddleware = (
   | ((req: KyukoRequest, res: KyukoResponse) => void)
   | ((req: KyukoRequest, res: KyukoResponse) => Promise<void>)
 );
 
-/**
- * Request that gets passed into a `KyukoRequestHandler`.
- * Can be extended further for middlewares to populate the original `Request`.
- */
-export interface KyukoRequest extends Request {
-  /**
-   * Stores path parameters and their values in an object.
-   */
-  params: {
-    [key: string]: string;
-  };
-
-  /**
-   * Stores query parameters and their values.
-   * Note that duplicate keys may map to different values.
-   */
-  query: URLSearchParams;
-}
-
 /**
  * An ultra-light framework for API servers hosted on [Deno Deploy](https://deno.com/deploy).
  * Aims to provide a similar experience to developing API servers with [Express](https://expressjs.com/).
@@ -57,7 +39,13 @@ export class Kyuko {
 
   /**
    * Initializes a new Kyuko app.
-   * Supports routing for GET, POST, PUT, DELETE methods as of now.
+   * Supports routing for the following methods as of now:
+   *   - GET
+   *   - POST
+   *   - PUT
+   *   - DELETE
+   *   - PATCH
+   *   - HEAD
    */
   constructor() {
     this.#routes = new RoutePathHandler();
@@ -195,10 +183,8 @@ export class Kyuko {
   }
 
   private handleFetchEvent(event: FetchEvent) {
-    const req = event.request as KyukoRequest;
-    req.params = {};
-    req.query = new URLSearchParams();
-    const res = new KyukoResponse(event);
+    const req = new KyukoRequestImpl(event);
+    const res = new KyukoResponseImpl(event);
     this.handleRequest(req, res);
   }
 

src/KyukoRequest.ts

@@ -0,0 +1,41 @@
+// Copyright 2021 Riki Singh Khorana. All rights reserved. MIT license.
+
+/// <reference path='./deploy.d.ts' />
+
+/**
+ * The request object that is handled in Kyuko applications.
+ * Can be extended further for middlewares to populate the original `Request`.
+ */
+export interface KyukoRequest extends Request {
+  /**
+   * Stores path parameters and their values in an object.
+   */
+  params: {
+    [key: string]: string;
+  };
+
+  /**
+   * Stores query parameters and their values.
+   * Note that a single key may map to multiple different values.
+   */
+  query: URLSearchParams;
+}
+
+/**
+ * This class is instantiated when a fetch request is captured by a Kyuko application.
+ * The instance is populated by the original request handed over from the event listener.
+ */
+export class KyukoRequestImpl extends Request implements KyukoRequest {
+  params: { [key: string]: string };
+  query: URLSearchParams;
+
+  /**
+   * Instantiates a `KyukoRequest` based on the original `fetchEvent` request.
+   * @param fetchEvent The event that this request originated from.
+   */
+  constructor(fetchEvent: FetchEvent) {
+    super(fetchEvent.request);
+    this.params = {};
+    this.query = new URLSearchParams();
+  }
+}

KyukoResponse.ts → src/KyukoResponse.ts

@@ -1,13 +1,55 @@
+// Copyright 2021 Riki Singh Khorana. All rights reserved. MIT license.
+
 /// <reference path='./deploy.d.ts' />
 
 /**
- * This class is instantiated when a fetch request is captured by a Kyuko application.
- * The instance is responsible for storing information about the response to the request.
- * The response built is finally sent out on a `send()` call.
+ * The response object that is handled in Kyuko applications.
+ * Responsible for storing information about the response to the request,
+ * as well as sending the response via the `send()` and `redirect()` methods.
  *
  * Note that `send()` or `redirect()` **must** be called or else the request will hang.
  */
-export class KyukoResponse {
+export interface KyukoResponse {
+  body: BodyInit | null;
+  statusCode: number | undefined;
+  statusText: string | undefined;
+  headers: Headers;
+
+  /**
+   * Sets the status code to `status`, and returns `this`.
+   */
+  status(status: number): KyukoResponse;
+
+  /**
+   * Redirects the request to a new `address`.
+   * The `address` can be either a relative url path, or a full url.
+   * The optional `status` parameter can be used to set a custom status code.
+   * Otherwise overrides the current `res.statusCode` with 302.
+   *
+   * @param address The address to redirect to.
+   * @param status The status code of the response. Defaults to 302.
+   */
+  redirect(address: string, status?: number): void;
+
+  /**
+   * Sends a response to the original request that instantiated this object.
+   * The response is built using the public attributes of this object,
+   * which should've been set by the user beforehand.
+   *
+   * @param body A response body that would supersede `this.body`
+   */
+  send(body?: BodyInit): void;
+
+  /**
+   * @returns Whether the response was sent (`send()` was called) or not.
+   */
+  wasSent(): boolean;
+}
+
+/**
+ * This class is instantiated when a fetch request is captured by a Kyuko application.
+ */
+export class KyukoResponseImpl implements KyukoResponse {
   body: BodyInit | null;
   statusCode: number | undefined;
   statusText: string | undefined;
@@ -28,42 +70,23 @@ export class KyukoResponse {
     this.#fetchEvent = fetchEvent;
   }
 
-  /**
-   * Sets the status code to `status`, and returns `this`.
-   */
-  status(status: number): this {
+  status(status: number) {
     this.statusCode = status;
-    const statusText = KyukoResponse.STATUSES.get(status);
+    const statusText = KyukoResponseImpl.STATUSES.get(status);
     if (statusText !== undefined) {
       this.statusText = statusText;
     }
 
     return this;
   }
 
-  /**
-   * Redirects the request to a new `address`.
-   * The `address` can be either a relative url path, or a full url.
-   * The optional `status` parameter can be used to set a custom status code.
-   * Otherwise overrides the current `res.statusCode` with 302.
-   *
-   * @param address The address to redirect to.
-   * @param status The status code of the response. Defaults to 302.
-   */
-  redirect(address: string, status = 302): void {
+  redirect(address: string, status = 302) {
     this.status(status);
     this.headers.append("Location", encodeURI(address));
     this.send();
   }
 
-  /**
-   * Sends a response to the original request that instantiated this object.
-   * The response is built using the public attributes of this object,
-   * which should've been set by the user beforehand.
-   *
-   * @param body A response body that would supersede `this.body`
-   */
-  send(body?: BodyInit): void {
+  send(body?: BodyInit) {
     if (!this.#sent) {
       const response = new Response(
         body || this.body,
@@ -79,10 +102,7 @@ export class KyukoResponse {
     }
   }
 
-  /**
-   * @returns Whether the response was sent (`send()` was called) or not.
-   */
-  wasSent(): boolean {
+  wasSent() {
     return this.#sent;
   }
 

RoutePathHandler.test.ts → src/RoutePathHandler.test.ts

@@ -1,3 +1,5 @@
+// Copyright 2021 Riki Singh Khorana. All rights reserved. MIT license.
+
 import { assertEquals } from "https://deno.land/[email protected]/testing/asserts.ts";
 import { RoutePathHandler } from "./RoutePathHandler.ts";