Static IP guide

Making API requests with a static IP from a Node app on Google Cloud Run

A Cloud Run service reaches the internet through a dynamic IP pool by default, so the outbound address a request leaves from can change between revisions or scale-up events — which breaks allowlisting for any API partner that checks the caller's IP. Add your Fixie proxy URL as an environment variable and point axios at it, and every request leaves from the same fixed pair of addresses instead.

RuntimeNode.js and JavaScript
PlatformGoogle Cloud Run
DestinationAPI allowlisting
Fixie productFixie HTTP/S proxy

Recommended setup

Use Fixie HTTP/S proxy for HTTP and HTTPS requests to an API, webhook provider, or service that allowlists outbound IP addresses. Store the proxy value in FIXIE_URL, then configure Node.js to route outbound traffic through Fixie before connecting to API allowlisting.

Set up Fixie on Google Cloud Run

Create a Fixie HTTP/S proxy in the Fixie dashboard. Copy the proxy value into Cloud Run's Variables & Secrets section as FIXIE_URL, and copy the outbound IPs into the destination allowlist.

Implementation

The example below shows the core application-side change. Keep credentials in environment variables and avoid committing proxy, database, or API secrets.

Make an HTTP request through FIXIE_URL

const axios = require('axios');

const fixieUrl = new URL(process.env.FIXIE_URL);

axios.get('https://api.example.com/data', {
  proxy: {
    protocol: 'http',
    host: fixieUrl.hostname,
    // URL drops default ports, so fall back to 80 for Fixie's standard proxy port.
    port: Number(fixieUrl.port) || 80,
    auth: {
      username: fixieUrl.username,
      password: fixieUrl.password,
    },
  },
}).then((response) => {
  console.log(response.status);
});

Good to know

  • From the Console: open the service, click Edit & Deploy New Revision, then add the variable under the Containers tab's Variables & Secrets section.
  • From the terminal, gcloud run deploy <service-name> --set-env-vars FIXIE_URL="<proxy-url>" sets it and deploys in one step.

Allowlist and test the static IPs

  1. Open the Fixie dashboard and copy the outbound IP addresses for this proxy.
  2. Add both IPs to the API provider.
  3. Deploy the updated Node.js app on Google Cloud Run.
  4. Run a small connection test before sending production traffic.

Related guides

Related docs

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