Google Cloud Run Java Samples

This directory contains samples for Google Cloud Run. Cloud Run runs stateless containers on a fully managed environment or in your own GKE cluster.

Samples

Sample	Description	Deploy
Hello World ➥	Quickstart
Cloud Pub/Sub	Handling Pub/Sub push messages

For more Cloud Run samples beyond Java, see the main list in the Cloud Run Samples repository.

Setup

1. Set up for Cloud Run development

2. Clone this repository:

   git clone https://github.com/GoogleCloudPlatform/java-docs-samples.git
   

   Note: Some samples in the list above are hosted in other repositories. They are noted with the symbol "➥".

How to run a sample locally

1. Install docker locally

2. Build the sample container:

   export SAMPLE=<SAMPLE_NAME>
   cd $SAMPLE
   docker build --tag $SAMPLE .
   

3. Run containers locally

   With the built container:

   PORT=8080 && docker run --rm -p 8080:${PORT} -e PORT=${PORT} $SAMPLE
   

   Overriding the built container with local code:

   PORT=8080 && docker run --rm \
       -p 8080:${PORT} -e PORT=${PORT} \
       -v $PWD:/app $SAMPLE
   

   Injecting your service account key for access to GCP services:

   # Set the name of the service account key within the container
   export SA_KEY_NAME=my-key-name-123
   
   PORT=8080 && docker run --rm \
       -p 8080:${PORT} \
       -e PORT=${PORT} \
       -e GOOGLE_APPLICATION_CREDENTIALS=/tmp/keys/${SA_KEY_NAME}.json \
       -v $GOOGLE_APPLICATION_CREDENTIALS:/tmp/keys/${SA_KEY_NAME}.json:ro \
       -v $PWD:/app $SAMPLE
   

   • Use the --volume (-v) flag to inject the credential file into the container (assumes you have already set your GOOGLE_APPLICATION_CREDENTIALS environment variable on your machine)

   • Use the --environment (-e) flag to set the GOOGLE_APPLICATION_CREDENTIALS variable inside the container

Learn more about testing your container image locally.

Deploying

1. Set your GCP Project ID as an environment variable:

export GOOGLE_CLOUD_PROJECT=<PROJECT_ID>

2. Choose to push your image to Google Container Registry or submit a build to Cloud Build:

• Push the docker build to Google Container Registry:

docker tag $SAMPLE gcr.io/${GOOGLE_CLOUD_PROJECT}/${SAMPLE}
docker push gcr.io/${GOOGLE_CLOUD_PROJECT}/${SAMPLE}

Learn more about pushing and pulling images.

• Submit a build using Google Cloud Build:

gcloud builds submit --tag gcr.io/${GOOGLE_CLOUD_PROJECT}/${SAMPLE}

3. Deploy to Cloud Run:

gcloud beta run deploy $SAMPLE \
  --set-env-vars GOOGLE_CLOUD_PROJECT=${GOOGLE_CLOUD_PROJECT}  \
  --image gcr.io/${GOOGLE_CLOUD_PROJECT}/${SAMPLE}

Next Steps

• See building containers and deploying container images for more information.

• Dockerize a Spring Boot app without a Dockerfile using Jib.

• To improve Tomcat startup time, add -Djava.security.egd=file:/dev/./urandom to the Dockerfile's CMD instructions. This is acceptable for many applications. However, if your application does it's own key generation, such as for SSL, and you require greater security, you may prefer to not set java.security.egd.