Puppeteer Proxy Setup

Why Puppeteer needs two steps

Chromium takes the proxy from a launch flag, and that flag has no place for credentials. Authentication happens afterwards, per page:

The proxy is set for the whole browser process, so one browser equals one address. Run several browsers when you need several identities in parallel.

One browser per address

Launch with the endpoint, then call page.authenticate before the first navigation:

Node: browser per identity

const puppeteer = require('puppeteer');

async function browserFor(sessionId) {
  const browser = await puppeteer.launch({
    args: ['--proxy-server=http://proxy.sotaproxy.com:10000'],
  });
  const page = await browser.newPage();
  await page.authenticate({
    username: `login_c_US_s_${sessionId}_ttl_1h`,
    password: 'password',
  });
  return { browser, page };
}

const { page } = await browserFor(7);
await page.goto('https://example.com', { timeout: 30000 });

• Call authenticate on every new page, not once per browser. A page opened later starts unauthenticated and the first request comes back 407.
• Use a separate user data directory per browser. Otherwise profiles share cookies and the address separation buys you nothing.
• Close browsers you are done with. Each one holds an open connection to our endpoint, and a leak here looks like a rate limit later.
• For many parallel identities, Playwright contexts are cheaper than Puppeteer browsers. Consider it when the count passes about ten.

Puppeteer specifics