Proxy Fetch Server

by Nicholas C. Zakas

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Description

A Node.js server that uses a proxy agent to make fetch requests. Built with Hono, this server accepts POST requests with URLs to fetch through a configurable proxy.

The intended use is as a serverless function.

Installation

npm install @humanwhocodes/proxy-fetch-server

Usage

Starting the Server

You can start the server using npx:

npx @humanwhocodes/proxy-fetch-server

Configuration

The server is configured using environment variables:

• PROXY_URI (required) - The address of the proxy to use with the proxy agent
• PROXY_FETCH_KEY (optional) - The expected Bearer token in the Authorization header
• PORT (optional) - The port to start the server on (default: 8080)
• PROXY_TOKEN (optional) - The token that the proxy expects
• PROXY_TOKEN_TYPE (optional) - The token type prefix for the proxy (default: "Bearer")

Example:

PROXY_URI=http://proxy.example.com:8080 \
PROXY_FETCH_KEY=my-secret-key \
PORT=3000 \
PROXY_TOKEN=proxy-secret \
PROXY_TOKEN_TYPE=Bearer \
npx @humanwhocodes/proxy-fetch-server

Making Requests

Send a POST request to the root endpoint (/) with:

• Authorization header (optional): Bearer <PROXY_FETCH_KEY> - Required only if PROXY_FETCH_KEY is configured
• Request body: JSON object with a url property

Example using curl:

curl -X POST http://localhost:8080/ \
  -H "Authorization: Bearer my-secret-key" \
  -H "Content-Type: application/json" \
  -d '{"url": "https://example.com"}'

The server will:

1. Validate the Bearer token (if configured)
2. Fetch the specified URL through the configured proxy
3. Return the response with the same status code and content type

Programmatic Usage

You can also use this package programmatically:

import { createApp } from "@humanwhocodes/proxy-fetch-server";

const app = createApp({
	key: "my-secret-key",
	proxyUri: "http://proxy.example.com:8080",
	proxyToken: "proxy-secret",
	proxyTokenType: "Bearer",
});

// Use with your preferred Node.js server adapter

License

Copyright 2025 Nicholas C. Zakas

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.