@northscaler/google-pubsub-test-support

Google PubSub Test Support Library

Usage no npm install needed!

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README

google-pubsub-test-support

Handy-dandy Google PubSub integration testing utility that starts a local Docker container running the Google PubSub emulator if you're not running in a CI/CD pipeline. This allows you to run integration tests locally in a manner similar to how they'd be run in the CI/CD pipeline. This module does nothing when running in a CI build pipeline, because Google PubSub should be configured as part of the build via something like .gitlab-ci.yml's services element.

This package is intended to be installed in your project in devDependencies.

Your application must install its desired version of Google PubSub.

NOTE: requires Docker & a Unix-y shell (/usr/bin/env sh) to be available. This is not designed to run on Windows; PRs/MRs welcome.

See [src/test/integration/google-pubsub/google-pubsub.spec.js] for usage, but it's basically

const googlePubSubConnect = require('google-pubsub-test-support')

// one PubSub instance per unique project name will be returned
const pubsubs = await googlePubSubConnect({ projects: ['project1', 'project2']})

// now you can use any of the PubSub instances
const pubsub1 = pubsubs.project1
const pubsub2 = pubsubs.project2

Configuration

The default configuration is pretty conventional, with the sole exception of the default port that Google PubSub will listen on for clients. Instead of 8661, which might already be in use on developers' machines when they run integration tests, the default configuration uses 18661. It is a TODO to search for an available port.

NOTE: This module detects when it's running in a CI/CD pipeline by seeing if the environment variable CI is of nonzero length.

Environment variables

The following environment variables can be set to configure it:

  • GOOGLE_PUBSUB_TEST_SUPPORT_TAG: The tag of the Google PubSub Emulator Docker image or custom image to use, default "latest"
  • GOOGLE_PUBSUB_TEST_SUPPORT_PORT: visible client port on localhost to map to container port, default is content of google-pubsub/default-google-pubsub-test-port
  • GOOGLE_PUBSUB_TEST_SUPPORT_CONTAINER: name of container, default is content of file google-pubsub/default-google-pubsub-test-container
  • GOOGLE_PUBSUB_TEST_SUPPORT_CONTAINER_PORT: Google PubSub emulator client port in container, default 8681
  • GOOGLE_PUBSUB_TEST_SUPPORT_IMAGE: docker image name, default messagebird/gcloud-pubsub-emulator