Google Cloud Pub/Sub Emulator Image

Cloud Pub/Sub is a global service for real-time and reliable messaging and streaming data

This image provides a dockerized version of the Google Cloud Pub/Sub Emulator. It is intended to be used as a service on development environments (it SHOULD NOT be used in production environments). You can check Cloud Pub/Sub documentation on Google Cloud Platform documentation website.

Usage

The following shell statement show the most simple execution of the provided image. It will execute the Pub/Sub Emulator that will listen on port 8538.

docker run --rm --tty --interactive --publish 8538:8538 bigtruedata/gcloud-pubsub-emulator

The image is much more useful when it is used in a CD/CI automated environment. The following example shows how to configure the Pub/Sub Emulator to be used in a Wercker development pipeline.

box: python:3.5

dev:
  services:
    - name: pubsub
      id: bigtruedata/gcloud-pubsub-emulator
      cmd: start --host-port 0.0.0.0:8538

  steps:
    - script:
      name: Define Pub/Sub environment variables
      code: |
        ADDR=$PUBSUB_PORT_8538_TCP_ADDR
        PORT=$PUBSUB_PORT_8538_TCP_PORT
        export PUBSUB_EMULATOR_HOST=$ADDR:$PORT

    - internal/shell:
      cmd: bash

Configuration

The most important configuration parameters of the Pub/Sub emulator image are the host/port value the server will listen on and the directory where data files will be placed. By default, the image is configured to listen on 127.0.0.1:8538 and store its files in the /data directory. This behavior can be changed by providing the correct command-line options.

The following example shows how to start the Pub/Sub emulator to listen on 192.168.1.3:12345 and to store its files in the /pubsub-data directory.

docker run --rm --tty --interactive bigtruedata/gcloud-pubsub-emulator start --host-port=192.168.1.3:12345 --data-dir=/pubsub-data

NOTE: Wercker's documentation can be checked online on Wercker Documentation Website