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Node.js

Node.js is fully supported by Speedscale, but proxy behavior depends on the HTTP client library. Use this page for Node-specific proxy settings, TLS trust configuration, demo guidance, and the Proxymock local workflow.

Kubernetes Sidecar​

When Node.js runs with the Speedscale sidecar in forward or dual mode, sidecar injection alone is not enough for outbound capture. The Node runtime or client library must still use the sidecar's forward proxy on 127.0.0.1:4140.

For many apps this starts with:

export HTTP_PROXY=http://127.0.0.1:4140
export HTTPS_PROXY=http://127.0.0.1:4140

Some Node.js HTTP clients ignore those variables unless you also configure an agent or library-specific proxy setting. If tls-out is enabled, also trust the Speedscale CA with NODE_EXTRA_CA_CERTS.

See Proxy Modes and TLS Support for the shared sidecar behavior.

Demo App​

  • Public demo: speedscale/demo (node directory)
  • Stack: Express
  • Local run: npm install && npm start
  • Quick validation: curl http://localhost:3000/

This is the current public Node.js demo used for local Proxymock examples.

Proxymock​

Use this path for the fastest Node.js first success on a developer workstation.

  1. 1. Install and initialize Proxymock
    brew install speedscale/tap/proxymock
proxymock init

    Use browser sign-in by default. Use `proxymock init --api-key <your key>` only for CI or other headless environments.

  2. 2. Start recording
    git clone https://github.com/speedscale/demo
cd demo/node
proxymock record --app-port 3000 --out ./proxymock/recorded

    The app listens on port 3000 while proxymock records inbound traffic on 4143 and saves the capture in `./proxymock/recorded`.

  3. 3. Route traffic through the proxy and run the app
    cd demo/node
export HTTP_PROXY=http://127.0.0.1:4140
export HTTPS_PROXY=http://127.0.0.1:4140
npm install
npm start

    Many Node HTTP clients need explicit proxy support, so set the environment variables and client agent together when needed.

  4. 4. Generate one real workflow
    curl http://localhost:4143/
curl http://localhost:4143/nasa
curl http://localhost:4143/events
curl http://localhost:4143/bin

    Exercise the demo endpoints once so the recording reflects the real outbound calls.

  5. 5. Stop the recording, then run with mocks
    cd demo/node
proxymock mock --in ./proxymock/recorded
export HTTP_PROXY=http://127.0.0.1:4140
export HTTPS_PROXY=http://127.0.0.1:4140
npm start

    The mocked run should no longer need live downstream access.

  6. 6. Replay the same traffic against a change
    cd demo/node
proxymock replay --in ./proxymock/recorded --test-against http://localhost:3000

    Use replay as the regression check before shipping Node.js changes.

TLS Trust​

Node.js usually respects NODE_EXTRA_CA_CERTS. For the exact command and client-specific caveats, use the shared Language Configuration page.