Add multi-platform function adapters and CI workflow

Introduces adapters for Vercel, Netlify Edge, Deno Deploy, and Cloudflare Pages, each with platform-specific entry points and configuration files. Adds a GitHub Actions CI workflow for linting, type checking, and testing. Updates lint scripts to include adapters, improves type annotations in src/index.js, and fixes a type assertion in security tests.

adapters/functions/api/index.js

@@ -0,0 +1,91 @@
+/**
+ * Xget - High-performance acceleration engine for developer resources
+ * Copyright (C) 2025 Xi Xu
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/* eslint-disable no-undef, no-unused-vars */
+
+import { handleRequest } from '../src/index.js';
+
+/**
+ * Edge Function handler.
+ *
+ * @param {Request} request - Standard Web API Request object
+ * @param {Object} [context] - Platform-specific context (Netlify only)
+ * @param {Object} [context.geo] - Geolocation data (Netlify)
+ * @param {string} [context.ip] - Client IP address (Netlify)
+ * @param {Object} [context.env] - Environment variables (Netlify)
+ * @param {Function} [context.waitUntil] - Background task extension (Netlify)
+ * @returns {Promise<Response>} Standard Web API Response
+ *
+ * @example
+ * // Netlify invokes with context
+ * handler(request, { geo: {...}, ip: '1.2.3.4', env: {...}, waitUntil: fn })
+ *
+ * @example
+ * // Vercel invokes without context
+ * handler(request)
+ */
+export default async function handler(request, context) {
+  // Detect runtime environment
+  const isNetlify = context && (context.geo !== undefined || context.ip !== undefined);
+
+  // Normalize environment variables
+  // Netlify provides context.env, Vercel Edge uses globalThis
+  let envSource;
+  if (isNetlify) {
+    envSource = context.env || {};
+  } else if (typeof process !== 'undefined' && process.env) {
+    // Vercel or Node.js environment
+    envSource = process.env;
+  } else {
+    // Fallback for other environments
+    envSource = {};
+  }
+
+  const env = {
+    TIMEOUT_SECONDS: envSource.TIMEOUT_SECONDS,
+    MAX_RETRIES: envSource.MAX_RETRIES,
+    RETRY_DELAY_MS: envSource.RETRY_DELAY_MS,
+    CACHE_DURATION: envSource.CACHE_DURATION,
+    ALLOWED_METHODS: envSource.ALLOWED_METHODS,
+    ALLOWED_ORIGINS: envSource.ALLOWED_ORIGINS,
+    MAX_PATH_LENGTH: envSource.MAX_PATH_LENGTH,
+  };
+
+  // Create normalized execution context
+  const ctx = {
+    waitUntil: isNetlify && context.waitUntil
+      ? (promise) => context.waitUntil(promise)
+      : (promise) => {
+          // No-op on Vercel: background tasks not supported
+          // Cache writes will run synchronously instead
+          console.warn('waitUntil is not supported in Vercel Edge Runtime');
+        },
+    passThroughOnException: () => {
+      // Not supported on either platform in this context
+      console.warn('passThroughOnException is not universally supported');
+    }
+  };
+
+  // Delegate to the main request handler
+  return handleRequest(request, env, ctx);
+}
+
+// Vercel Edge Runtime configuration (ignored by Netlify)
+export const config = {
+  runtime: 'edge',
+};

adapters/functions/deno.js

@@ -0,0 +1,65 @@
+/**
+ * Xget - High-performance acceleration engine for developer resources
+ * Copyright (C) 2025 Xi Xu
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/* eslint-disable no-undef, no-unused-vars */
+
+import { handleRequest } from './src/index.js';
+
+/**
+ * Deno Deploy handler.
+ *
+ * This is the entry point for Deno Deploy deployments. It uses the
+ * standard Deno.serve() API to handle incoming HTTP requests.
+ *
+ * @param {Request} request - Standard Web API Request object
+ * @returns {Promise<Response>} Standard Web API Response
+ *
+ * @example
+ * // Deno Deploy invokes automatically:
+ * // Deno.serve((request) => handler(request))
+ */
+async function handler(request) {
+  // Extract environment variables from Deno.env
+  const env = {
+    TIMEOUT_SECONDS: Deno.env.get('TIMEOUT_SECONDS'),
+    MAX_RETRIES: Deno.env.get('MAX_RETRIES'),
+    RETRY_DELAY_MS: Deno.env.get('RETRY_DELAY_MS'),
+    CACHE_DURATION: Deno.env.get('CACHE_DURATION'),
+    ALLOWED_METHODS: Deno.env.get('ALLOWED_METHODS'),
+    ALLOWED_ORIGINS: Deno.env.get('ALLOWED_ORIGINS'),
+    MAX_PATH_LENGTH: Deno.env.get('MAX_PATH_LENGTH'),
+  };
+
+  // Create minimal ExecutionContext-like object
+  // Deno Deploy doesn't support waitUntil, so cache writes are synchronous
+  const ctx = {
+    waitUntil: (promise) => {
+      // No-op on Deno: background tasks not supported
+      console.warn('waitUntil is not supported in Deno Deploy');
+    },
+    passThroughOnException: () => {
+      console.warn('passThroughOnException is not supported in Deno Deploy');
+    }
+  };
+
+  // Delegate to the main request handler
+  return handleRequest(request, env, ctx);
+}
+
+// Start the server
+Deno.serve(handler);

adapters/functions/netlify.toml

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+[[edge_functions]]
+function = "edge-handler"
+path = "/*"
+
+[build]
+publish = "."

adapters/functions/netlify/edge-functions/edge-handler.js

@@ -0,0 +1,13 @@
+/**
+ * Netlify Edge Function entry point.
+ *
+ * This file serves as a redirect to the edge function handler
+ * located at /api/index.js. Both Netlify and Vercel can use the same
+ * handler code, with platform detection handling the differences.
+ *
+ * Netlify requires edge functions to be in netlify/edge-functions/,
+ * while Vercel uses /api/ directory. This approach maintains a single
+ * source of truth at /api/index.js.
+ */
+export { config, default } from '../../api/index.js';
+

adapters/functions/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "xget",
+  "version": "1.0.0",
+  "type": "module",
+  "private": false,
+  "scripts": {
+    "dev": "vercel dev",
+    "deploy": "vercel --prod",
+    "vercel-build": "echo 'No build step required'"
+  },
+  "dependencies": {
+    "express": "^4.19.2"
+  },
+  "devDependencies": {
+    "@vercel/node": "^3.0.0"
+  }
+}

adapters/functions/vercel.json

@@ -0,0 +1,22 @@
+{
+  "$schema": "https://openapi.vercel.sh/vercel.json",
+  "name": "xget",
+  "version": 2,
+  "rewrites": [
+    {
+      "source": "/(.*)",
+      "destination": "/api/index.js"
+    }
+  ],
+  "headers": [
+    {
+      "source": "/(.*)",
+      "headers": [
+        {
+          "key": "X-Powered-By",
+          "value": "Xget/Vercel"
+        }
+      ]
+    }
+  ]
+}

adapters/pages/functions/[[path]].js

@@ -0,0 +1,70 @@
+/**
+ * Xget - High-performance acceleration engine for developer resources
+ * Copyright (C) 2025 Xi Xu
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/* eslint-disable no-undef */
+
+import { handleRequest } from '../src/index.js';
+
+/**
+ * Pages Function handler for all routes.
+ *
+ * This catch-all route handler processes all incoming requests to the Xget
+ * acceleration engine. It delegates request processing to the main handleRequest
+ * function from the Workers code, maintaining full compatibility with the
+ * existing implementation.
+ *
+ * The [[path]] syntax in the filename creates a catch-all route that matches
+ * any path, allowing this single function to handle all requests to the Pages
+ * application.
+ *
+ * @param {Object} context - Pages Function context
+ * @param {Request} context.request - The incoming HTTP request
+ * @param {Object} context.env - Environment variables and bindings (KV, secrets, etc.)
+ * @param {Object} context.params - Route parameters (path segments from [[path]])
+ * @param {Function} context.waitUntil - Extend function execution for background tasks
+ * @param {Function} context.next - Call next middleware in chain (not used here)
+ * @param {Object} context.data - Shared data between functions
+ * @returns {Promise<Response>} The HTTP response to return to the client
+ *
+ * @example
+ * // This is called automatically by Pages
+ * // Runtime invokes: onRequest(context)
+ * // Returns: Response with package data
+ *
+ * @example
+ * // Environment variables usage
+ * // wrangler.toml: [vars] TIMEOUT_SECONDS = "60"
+ * // context.env contains: { TIMEOUT_SECONDS: "60" }
+ * // handleRequest uses createConfig(env) to override defaults
+ */
+export async function onRequest(context) {
+  // Extract request, env, and create an execution context compatible with Workers
+  const { request, env, waitUntil } = context;
+
+  // Create a minimal ExecutionContext-like object for compatibility
+  const ctx = {
+    waitUntil: waitUntil,
+    passThroughOnException: () => {
+      // Pages doesn't support passThroughOnException, so this is a no-op
+      console.warn('passThroughOnException is not supported in Pages Functions');
+    }
+  };
+
+  // Delegate to the main request handler
+  return handleRequest(request, env, ctx);
+}

adapters/pages/wrangler.toml

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+#:schema node_modules/wrangler/config-schema.json
+name = "xget"
+pages_build_output_dir = "."
+compatibility_date = "2024-10-22"
+compatibility_flags = ["nodejs_compat"]