create fake pubsub

Dockerfile

@@ -0,0 +1,13 @@
+FROM google/cloud-sdk:alpine
+MAINTAINER contentdev
+
+RUN apk --update add openjdk8-jre
+RUN gcloud components install pubsub-emulator beta --quiet
+
+VOLUME /opt/data
+
+COPY start-pubsub.sh .
+
+EXPOSE 8432
+
+ENTRYPOINT ["./start-pubsub.sh"]

README.md

@@ -1,2 +1,52 @@
-# pubsub-emulator
-pub-sub emulator running in docker
+
+# Google Cloud Pub/Sub Emulator
+
+A [Google Cloud Pub/Sub Emulator](https://cloud.google.com/pubsub/docs/emulator) container image. The image is meant to be used for creating an standalone emulator for testing.
+Copied from: [pubsub-emulator-docker](https://github.com/SingularitiesCR/pubsub-emulator-docker) and updated the google sdk version since that repository has been archived
+
+## Environment
+
+The following environment variables must be set:
+
+- `PUBSUB_LISTEN_ADDRESS`: The address should refer to a listen address, meaning that `0.0.0.0` can be used. The address must use the syntax `HOST:PORT`, for example `0.0.0.0:8432`. The container must expose the port used by the Pub/Sub emulator.
+- `PUBSUB_PROJECT_ID`: The ID of the Google Cloud project for the emulator.
+
+## Connect application with the emulator
+
+The following environment variables need to be set so your application connects to the emulator instead of the production Cloud Pub/Sub environment:
+
+- `PUBSUB_EMULATOR_HOST`: The listen address used by the emulator.
+- `PUBSUB_PROJECT_ID`: The ID of the Google Cloud project used by the emulator.
+
+## Custom commands
+
+This image contains a script named `start-pubsub` (included in the PATH). This script is used to initialize the Pub/Sub emulator.
+
+### Starting an emulator
+
+By default, the following command is called:
+
+```sh
+start-pubsub
+```
+
+## Creating a Pub/Sub emulator with Docker Compose
+
+The easiest way to create an emulator with this image is by using [Docker Compose](https://docs.docker.com/compose). The following snippet can be used as a `docker-compose.yml` for a Pub/Sub emulator:
+
+```YAML
+version: "2"
+
+services:
+  pubsub:
+    image: singularities/pubsub-emulator
+    environment:
+      - PUBSUB_PROJECT_ID=project-test
+      - PUBSUB_LISTEN_ADDRESS=0.0.0.0:8432
+    ports:
+      - "8432:8432"
+```
+
+### Persistence
+
+The image has a volume mounted at `/opt/data`. To maintain states between restarts, mount a volume at this location.

start-pubsub.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+if [[ -z "${PUBSUB_PROJECT_ID}" ]]; then
+  echo "Missing PUBSUB_PROJECT_ID environment variable" >&2
+  exit 1
+fi
+
+if [[ -z "${PUBSUB_LISTEN_ADDRESS}" ]]; then
+  echo "Missing PUBSUB_LISTEN_ADDRESS environment variable" >&2
+  exit 1
+fi
+
+gcloud config set project ${PUBSUB_PROJECT_ID}
+
+gcloud beta emulators pubsub start \
+  --data-dir=/opt/data \
+  --host-port=${PUBSUB_LISTEN_ADDRESS}