docs(drash/v2.x): Add documentation for using prefixes

docs/drash/v2.x/2_tutorials/2_resources/3_using_dynamic_paths.md

@@ -144,4 +144,4 @@ This resource would not handle the following URIs because they do not match the
 * `GET /11`
 * `GET /12`
 * `GET /13`
-* `GET /99`
+* `GET /99`

docs/drash/v2.x/2_tutorials/2_resources/4_prefixing_paths.md

@@ -0,0 +1,167 @@
+# Prefixing Paths
+
+Sometimes you may want to prefix your paths with `/web`, `/api/v1`, or something else that meets your requirements. By default, Drash does not have any built-in, magic code that allows you to do this. However, since Drash is extensible, the implementation is quite simple.
+
+## Table of Contents
+
+* [Before You Get Started](#before-you-get-started)
+* [Folder Structure End State](#folder-structure-end-state)
+* [Steps](#steps)
+* [Verification](#verification)
+
+## Before You Get Started
+
+In this tutorial, we will go over one way to introduce path prefixing.
+
+Please note that the steps below outline just a single way of implementing path prefixes. You can take this tutorial as inspiration to create your own preferred implementation.
+
+## Folder Structure End State
+
+```text
+▾  website/
+  ▾  resources/api/
+    ▾  v1/
+         users_resource.ts
+    ▾  v2/
+         users_resource.ts
+       base_resource.ts
+     app.ts
+     deps.ts
+```
+
+## Steps
+
+1. Create your `app.ts` file.
+
+  ```typescript
+  // app.ts
+
+  import { Drash } from "./deps.ts";
+  import { UsersResource as v1UsersResource } from "./resources/api/v1/users_resource.ts";
+  import { UsersResource as v2UsersResource } from "./resources/api/v2/users_resource.ts";
+
+  const server = new Drash.Server({
+    hostname: "0.0.0.0",
+    port: 1447,
+    protocol: "http",
+    resources: [
+      v1UsersResource,
+      v2UsersResource,
+    ],
+  });
+
+  server.run();
+
+  console.log(`Server running at ${server.address}.`);
+  ```
+
+2. Create your `BaseResource` class. When resources extend this class, they can use the `prefixPaths()` method to prefix their paths.
+
+  ```ts
+  // resources/api/base_resource.ts
+
+  import { Drash } from "../../deps.ts";
+
+  export class BaseResource extends Drash.Resource {
+
+    /**
+     * Define a list of prefixes that can be used by resources that extend this class.
+     */
+    #prefixes: {[k: string]: string} = {
+      api_v1: "/api/v1",
+      api_v2: "/api/v2",
+    }
+
+    /**
+     * Returns the passed in array with each path being prefixed
+     *
+     * @param prefix - The prefix to use
+     * @param paths - The resource paths to prefix
+     *
+     * @returns The `paths` parameter, but with every item prefixed with `this.#prefix`
+     */
+    protected prefixPaths(prefix: string, paths: string[]) {
+      return paths.map(path => this.#prefixes[prefix] + path);
+    }
+  }
+  ```
+
+3. Add a v1 `UsersResource` by extending `BaseResource` and choosing the `/api/v1` prefix.
+
+  ```ts
+  // resources/api/v1/users_resource.ts
+
+  import { Drash } from "../../../deps.ts";
+  import { BaseResource } from "../base_resource.ts";
+
+  export class UsersResource extends BaseResource {
+
+    public paths = this.prefixPaths("api_v1", ["/users", "/users/:id"]);
+    // The above will be transformed to the following:
+    //
+    //   - /api/v1/users
+    //   - /api/v1/users/:id
+
+    public GET(request: Drash.Request, response: Drash.Response): void {
+      return response.text("Hello from v1!");
+    }
+  }
+  ```
+
+4. Add a v2 `UsersResource` by extending `BaseResource` and choosing the `/api/v2` prefix.
+
+  ```ts
+  // resources/api/v2/users_resource.ts
+
+  import { Drash } from "../../../deps.ts";
+  import { BaseResource } from "../base_resource.ts";
+
+  export class UsersResource extends BaseResource {
+
+    public paths = this.prefixPaths("api_v2", ["/users", "/users/:id"]);
+    // The above will be transformed to the following:
+    //
+    //   - /api/v2/users
+    //   - /api/v2/users/:id
+
+    public GET(request: Drash.Request, response: Drash.Response): void {
+      return response.text("Hello from v2!");
+    }
+  }
+  ```
+
+Note that you can take the above steps and apply them to all of your resources (assuming they all need a prefix). Just create a base resource once and for every resource that needs a prefix, just extend the base resource and define the paths like in the above steps.
+
+If only some of your resources need a prefix, they can still extend the base resource, but they do not need to call the `prefixPaths()` method.
+
+## Verification
+
+1. Run your app.
+
+  ```shell
+  $ deno run --allow-net app.ts
+  ```
+
+2. Using `curl` (or similar command), make a `GET` request to `http://localhost:1447/api/v1/users`.
+
+  ```text
+  $ curl http://localhost:1447/api/v1/users
+  ```
+
+  You should receive the following response:
+
+  ```text
+  Hello from v1!
+  ```
+
+3. Make another request, but to `http://localhost:1447/api/v2/users`.
+
+  ```text
+  $ curl http://localhost:1447/api/v2/users
+  ```
+
+  You should receive the following response:
+
+  ```text
+  Hello from v2!
+  ```