Prerequisites:

• Message broker (Google PubSub)
  • Run PubSub Emulator locally
• MySQL database
  • Run MySQL locally
  • Import sample data to the DB

Run PubSub Emulator locally

You may inspect local/pubsub/Dockerfile file to get some information regarding the docker image which provides PubSub emulator. To run PubSub in a container execute the following commands:

# Go to the folder containing Dockerfile
cd local/pubsub

# Build an image with PubSub emulator: 
docker build -t pubsub-local .

# Run the PubSub emulator in a container: 
docker run -p "8085:8085" --name pubsub_emulator -d pubsub-local

This will give you a PubSub service available on the 8085 port, so you are able to connect to it using localhost:8085 address.

Configure SpringBoot to use PubSub emulator

To use PubSub emulator with your application you should provide the following application property via application.yml

spring:
  cloud:
    gcp:
      pubsub:
        emulator-host: localhost:8085

or application.properties

spring.cloud.gcp.pubsub.emulator-host=localhost:8085

For any other application types (non Spring Boot) you should provide PUBSUB_EMULATOR_HOST environment variable. Example:

export PUBSUB_EMULATOR_HOST=localhost:8085

Configure PubSub service account to use GCP service

In case if you want to use cloud provider (GCP) service then please perform the following steps:

• In the https://console.cloud.google.com/ setup PubSub
  • there is a useful documentation https://cloud.google.com/pubsub/docs/spring
• Download a private key file with credentials as JSON file
• Add environment variable to execute microservices with GCP credentials: GOOGLE_APPLICATION_CREDENTIALS=<path-to-credentials-file>.json
• Remove emulator reference from the application properties: spring.cloud.gcp.pubsub.emulator-host=localhost:8085

Run MySQL in docker container

Execute the following script to launch MySQL in Docker and to create required databases:

local/db/run-local-mysql.sh

The MySQL server will be launched at the default 3306 port, and the root user password will be root.

Import sample data to the DB

You may use sample data from the local/db/data/*.csv files for import into your DB, so you will have something to start with.