Add API prefix support for routes and middleware

- Introduced `--enable-api-prefix` option for CLI and programmatic usage
- Implemented `apiPrefixMiddleware` to handle `/api/*` routing
- Updated documentation to reflect new API prefix feature
- Modified relevant tests to include API prefix scenarios

Author: webmasterdevlin

README.md

@@ -11,6 +11,7 @@ A TypeScript implementation of json-server with additional features and comprehe
 - Full TypeScript support with type definitions
 - RESTful API endpoints from a JSON file or JavaScript object
 - Configurable routes
+- API prefix support (`/api/*` for all routes)
 - Support for multiple package managers (npm, yarn, pnpm, bun)
 - CORS support
 - Delay simulation for network latency testing
@@ -178,6 +179,7 @@ Options:
   --read-only, --ro  Allow only GET requests                  [default: false]
   --no-cors, --nc    Disable CORS                             [default: false]
   --no-gzip, --ng    Disable GZIP compression                 [default: false]
+  --enable-api-prefix, --api  Enable /api/* prefix            [default: false]
   --delay, -d        Add delay to responses (ms)                       [number]
   --id, -i           Set database id field                     [default: "id"]
   --foreignKeySuffix Set foreign key suffix               [default: "_id"]
@@ -203,6 +205,50 @@ GET /posts?_sort=title&_order=asc
 GET /posts?_sort=title&_order=desc
 ```
 
+## API Prefix
+
+The API prefix feature allows you to access all your resources with an `/api` prefix. This is useful when:
+
+- You want to make your mock API feel more like a real backend
+- You need to differentiate API routes from other routes in your application
+- You're working with frontend frameworks that expect API routes to start with `/api`
+
+### Using API Prefix with CLI
+
+Enable the API prefix feature using the `--enable-api-prefix` (or `-api` shorthand) flag:
+
+```bash
+json-server db.json --enable-api-prefix
+```
+
+This allows you to access resources through both standard and API-prefixed routes:
+
+```
+# Standard routes still work
+GET /posts
+GET /posts/1
+
+# API-prefixed routes also work
+GET /api/posts
+GET /api/posts/1
+```
+
+### Using API Prefix Programmatically
+
+```typescript
+import { create } from '@webmasterdevlin/json-server';
+
+const server = create({
+  port: 3000,
+  enableApiPrefix: true, // Enable the API prefix feature
+});
+
+server.loadDatabase('./db.json');
+server.start().then(() => {
+  console.log('Server running with API prefix support');
+});
+```
+
 ## Programmatic Usage
 
 ```typescript
@@ -220,6 +266,7 @@ const server = create({
   host: 'localhost',
   readOnly: false, // Allow all HTTP methods
   delay: 1000, // Add 1s delay to responses
+  enableApiPrefix: true, // Enable /api/* prefix for all routes
 });
 
 // Create a custom route

mod.ts

@@ -4,13 +4,19 @@
  * This module provides a Deno-compatible interface for json-server.
  * It can be used both as a CLI and as a programmatic API from Deno scripts.
  *
+ * Features include:
+ * - TypeScript-powered JSON Server with API prefix support
+ * - RESTful API with custom routes
+ * - Configurable settings for CORS, delay, read-only mode
+ * - API prefix (/api/*) routing via the enableApiPrefix option
+ *
  * @example
  * // Run from command line:
- * // deno run --allow-read --allow-write --allow-net --allow-run mod.ts db.json --port 3001
+ * // deno run --allow-read --allow-write --allow-net --allow-run mod.ts db.json --port 3001 --enable-api-prefix
  *
  * // Import programmatically:
  * // import { create } from "./mod.ts";
- * // const server = create({ port: 3000 });
+ * // const server = create({ port: 3000, enableApiPrefix: true });
  * // server.loadDatabase("./db.json");
  * // await server.start();
  *
@@ -43,6 +49,7 @@ Options:
   --id, -i           Set database id field                     [default: "id"]
   --read-only, --ro  Allow only GET requests                  [default: false]
   --no-cors, --nc    Disable CORS                             [default: false]
+  --enable-api-prefix, --api  Enable /api/* prefix            [default: false]
   --quiet, -q        Suppress log messages                    [default: false]
   --help, -h         Show help                                        [boolean]
   --version, -v      Show version                                     [boolean]
@@ -51,6 +58,7 @@ Examples:
   deno run --allow-read --allow-write --allow-net --allow-run mod.ts db.json
   deno run --allow-read --allow-write --allow-net --allow-run mod.ts db.json --port 3001
   deno run --allow-read --allow-write --allow-net --allow-run mod.ts db.json --delay 500
+  deno run --allow-read --allow-write --allow-net --allow-run mod.ts db.json --enable-api-prefix
   `);
 }
 
@@ -71,6 +79,7 @@ if (import.meta.main) {
       q: 'quiet',
       nc: 'no-cors',
       ro: 'read-only',
+      api: 'enable-api-prefix',
     },
   });
 
@@ -129,6 +138,7 @@ if (import.meta.main) {
     delay: args.delay || 0,
     quiet: args.quiet || false,
     readOnly: args['read-only'] || false,
+    enableApiPrefix: args['enable-api-prefix'] || false,
   };
 
   try {

src/bin/index.ts

@@ -7,6 +7,13 @@
  * It parses command line arguments and starts a server instance
  * with the specified configuration.
  *
+ * The CLI supports several features including:
+ * - Database loading from local or remote files
+ * - Custom routes and middleware
+ * - API prefix support (/api/* routes)
+ * - Delay simulation for network latency testing
+ * - Read-only mode for safe demonstrations
+ *
  * @author webmasterdevlin
  * @copyright MIT License
  */
@@ -44,6 +51,7 @@ function parseArgs(): CliArgs {
     ro: 'read-only',
     nc: 'no-cors',
     ng: 'no-gzip',
+    api: 'enable-api-prefix', // Short alias for enabling API prefix
   };
 
   // Parse command line arguments with minimist
@@ -106,6 +114,7 @@ Options:
   --read-only, --ro  Allow only GET requests                  [default: false]
   --no-cors, --nc    Disable CORS                             [default: false]
   --no-gzip, --ng    Disable GZIP compression                 [default: false]
+  --enable-api-prefix, --api  Enable /api/* prefix            [default: false]
   --delay, -d        Add delay to responses (ms)                       [number]
   --id, -i           Set database id field                     [default: "id"]
   --foreignKeySuffix Set foreign key suffix               [default: "_id"]
@@ -121,6 +130,7 @@ Examples:
   json-server db.json --routes routes.js
   json-server db.json --delay 1000
   json-server db.json --id _id
+  json-server db.json --enable-api-prefix     # Enable /api/* routes
   json-server http://example.com/db.json
 
 For more information, visit:
@@ -177,6 +187,7 @@ async function main(): Promise<void> {
       delay: cliArgs.delay || 0,
       quiet: cliArgs.quiet || false,
       readOnly: cliArgs['read-only'] || false,
+      enableApiPrefix: cliArgs['enable-api-prefix'] || false, // Enable API prefix feature if specified
     };
 
     // Create and configure the server

src/index.ts

@@ -5,6 +5,12 @@
  * It provides factory functions, classes, types, and utilities
  * for creating and managing JSON API servers.
  *
+ * The package includes features such as:
+ * - RESTful API with TypeScript support
+ * - Custom route configuration
+ * - API prefix support (/api/* for all routes)
+ * - CORS, read-only mode, and delay simulation
+ *
  * @author webmasterdevlin
  * @copyright MIT License
  */
@@ -19,7 +25,13 @@ import {
   HttpMethod,
   RouteHandler,
 } from './types';
-import { delayMiddleware, corsMiddleware, readOnlyMiddleware, CorsConfig } from './middleware';
+import {
+  delayMiddleware,
+  corsMiddleware,
+  readOnlyMiddleware,
+  apiPrefixMiddleware,
+  CorsConfig,
+} from './middleware';
 import * as utils from './utils/utils';
 
 /**
@@ -34,7 +46,8 @@ import * as utils from './utils/utils';
  * const server = create({
  *   port: 3001,
  *   delay: 500,
- *   readOnly: true
+ *   readOnly: true,
+ *   enableApiPrefix: true // Enable /api/* prefix for all routes
  * });
  *
  * // Load database and start server
@@ -58,6 +71,7 @@ export function create(options: Partial<ServerOptions> = {}): JsonServer {
     delay: options.delay || 0,
     quiet: options.quiet || false,
     readOnly: options.readOnly || false,
+    enableApiPrefix: options.enableApiPrefix || false,
   };
 
   return createServer(serverOptions);
@@ -82,6 +96,7 @@ export {
   delayMiddleware,
   corsMiddleware,
   readOnlyMiddleware,
+  apiPrefixMiddleware,
   CorsConfig,
 
   // Utilities

src/lib/server.ts

@@ -5,7 +5,12 @@ import bodyParser from 'body-parser';
 import morgan from 'morgan';
 import serveStatic from 'serve-static';
 import { ServerOptions, Database, RoutesConfig, HttpMethod } from '../types';
-import { corsMiddleware, delayMiddleware, readOnlyMiddleware } from '../middleware';
+import {
+  corsMiddleware,
+  delayMiddleware,
+  readOnlyMiddleware,
+  apiPrefixMiddleware,
+} from '../middleware';
 import { fileExists, loadJsonFile, saveJsonFile, parseRoutesFile } from '../utils/utils';
 
 /**
@@ -68,6 +73,15 @@ export class JsonServer {
       this.app.use(bodyParser.urlencoded({ extended: false, limit: '10mb' }));
     }
 
+    // API Prefix middleware - allows accessing routes with /api/* prefix
+    // This enables both standard routes (/users) and prefixed routes (/api/users)
+    if (this.options.enableApiPrefix) {
+      this.app.use(apiPrefixMiddleware(this.options.enableApiPrefix));
+      if (!this.options.quiet) {
+        console.log('API prefix middleware enabled. Routes can be accessed with /api/* prefix.');
+      }
+    }
+
     // Delay middleware for simulating network latency
     if (this.options.delay > 0) {
       this.app.use(delayMiddleware(this.options.delay));

src/middleware/apiPrefix.ts

@@ -0,0 +1,46 @@
+import { Request, Response, NextFunction, RequestHandler } from 'express';
+
+/**
+ * Creates middleware to handle API prefix routing
+ *
+ * This middleware allows requests to be made with an /api prefix,
+ * automatically stripping the prefix before processing the request.
+ * For example, a request to /api/users will be treated as /users internally.
+ *
+ * This feature is useful when:
+ * - You want to make your mock API feel more like a real backend
+ * - You need to differentiate API routes from other routes in your application
+ * - You're working with frontend frameworks that expect API routes to start with /api
+ *
+ * Both standard routes (/users) and API-prefixed routes (/api/users) will work
+ * simultaneously when this middleware is enabled.
+ *
+ * @param enableApiPrefix - Whether to enable API prefix routing (default: true)
+ * @returns Express middleware function
+ *
+ * @example
+ * // Usage in Express application
+ * app.use(apiPrefixMiddleware(true));
+ *
+ * // This will allow both these requests to work:
+ * // GET /users
+ * // GET /api/users
+ */
+export function apiPrefixMiddleware(enableApiPrefix: boolean = true): RequestHandler {
+  // If API prefix is disabled, return a pass-through middleware
+  if (!enableApiPrefix) {
+    return (_req: Request, _res: Response, next: NextFunction): void => {
+      next();
+    };
+  }
+
+  return (req: Request, _res: Response, next: NextFunction): void => {
+    // Check if the request path starts with /api/
+    if (req.path.startsWith('/api/')) {
+      // Rewrite the URL by removing the /api prefix
+      req.url = req.url.replace(/^\/api/, '');
+    }
+
+    next();
+  };
+}

src/middleware/index.ts

@@ -3,11 +3,12 @@
  *
  * This file exports all middleware components for the json-server package.
  * These middlewares handle common HTTP server functionality such as CORS,
- * response delays, and read-only mode.
+ * response delays, read-only mode, and API prefix routing.
  */
 
 import { corsMiddleware, CorsConfig } from './cors';
 import { delayMiddleware } from './delay';
 import { readOnlyMiddleware } from './readOnly';
+import { apiPrefixMiddleware } from './apiPrefix';
 
-export { corsMiddleware, delayMiddleware, readOnlyMiddleware, CorsConfig };
+export { corsMiddleware, delayMiddleware, readOnlyMiddleware, apiPrefixMiddleware, CorsConfig };

src/types/index.ts

@@ -37,6 +37,13 @@ export interface ServerOptions {
 
   /** Whether to make the server read-only (no POST, PUT, PATCH, DELETE) */
   readOnly: boolean;
+
+  /**
+   * Whether to enable API prefix (/api/*) for all routes
+   * When enabled, all routes can be accessed both directly (/users)
+   * and with an /api prefix (/api/users)
+   */
+  enableApiPrefix: boolean;
 }
 
 /**
@@ -92,6 +99,12 @@ export interface CliArgs {
   /** Path to file for database snapshots */
   snapshot?: string;
 
+  /**
+   * Whether to enable API prefix feature
+   * When enabled, all routes can be accessed with /api/* prefix
+   */
+  'enable-api-prefix'?: boolean;
+
   /** Additional, unknown command line arguments */
   [key: string]: any;
 }