Set environment variables to configure builds

You can configure environment variables that are set during the build of your container image.

You can also customize your container image by extending the build and run images.

Local builds

For local builds, you must have the Pack CLI and Docker installed.

Before you begin

1. Install Docker Community Edition (CE) on your workstation. Docker is used by pack as an OCI image builder.
2. Install Pack CLI.
3. Install the Git source control tool to fetch the sample application from GitHub.

Set environment variables

To set environment variables for local builds, you append the --env flag to the pack command for each environment variable.

You can use one or more of the environment variables that are supported by your runtime.

pack build SERVICE_NAME \
    --env ENVIRONMENT_VARIABLE

Replace:

• SERVICE_NAME with the name of the service for your application or function.
• ENVIRONMENT_VARIABLE with the environment variable that you want to set during build time.

Example

To set the GOOGLE_ENTRYPOINT="gunicorn -p :8080 main:app" environment variable in your container image, you run the following command:

pack build my-app \
    --builder gcr.io/buildpacks/builder:v1 \
    --env GOOGLE_ENTRYPOINT="gunicorn -p :8080 main:app"
    --env MY-LOCAL-ENV-VARIABLE

Remote builds

To set environment variables for remote builds, you use the project.toml project descriptor. The project.toml project descriptor is used by Cloud Build when your container image is built.

Before you begin

1. Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.

2. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

3. Make sure that billing is enabled for your Google Cloud project.

4. Enable the Cloud Build and Artifact Registry APIs.

   Enable the APIs

5. Install the Google Cloud CLI.

6. To initialize the gcloud CLI, run the following command:

   gcloud init

7. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

8. Make sure that billing is enabled for your Google Cloud project.

9. Enable the Cloud Build and Artifact Registry APIs.

   Enable the APIs

10. Install the Google Cloud CLI.

11. To initialize the gcloud CLI, run the following command:

    gcloud init

If you've already installed Google Cloud CLI previously, make sure you have the latest available version by running gcloud components update.

12. Ensure that your Google Cloud project has access to a container image repository.

    To configure access to a Docker repository in Artifact Registry:

    1. Create a new Docker repository in the same location of your Google Cloud project.

       gcloud artifacts repositories create REPO_NAME \
       --repository-format=docker \
       --location=REGION --description="DESCRIPTION"

       Replace:
       • REPO_NAME with the name that you choose for your Docker repository.
       • REGION with the location in or nearest to the location of your Google Cloud project.
       • DESCRIPTION with a description of your choice.

       For example, to create a docker repository in us-west2 with the description "Docker repository", you run:

       gcloud artifacts repositories create buildpacks-docker-repo --repository-format=docker \
       --location=us-west2 --description="Docker repository"

    2. Verify that your repository was created:

       gcloud artifacts repositories list

       You should see name that you choose for your Docker repository in the list.

Optional: Download a sample application

1. Clone the sample repository to your local machine:

   git clone https://github.com/GoogleCloudPlatform/buildpack-samples.git

2. Change to the directory that contains the application sample code:

   Go

   cd buildpack-samples/sample-go

   Java

   cd buildpack-samples/sample-java-gradle

   Node.js

   cd buildpack-samples/sample-node

   PHP

   cd buildpack-samples/sample-php

   Python

   cd buildpack-samples/sample-python

   Ruby

   cd buildpack-samples/sample-ruby

   .NET

   cd buildpack-samples/sample-dotnet

Build the application with environment variables

1. In the root directory of your service, create or update your project.toml project descriptor to include the [[build.env]] section and any of the supported environment variable:

   [[build.env]]
       name = "ENVIRONMENT_VARIABLE_NAME"
       value = "ENVIRONMENT_VARIABLE_VALUE"

   Replace:

   • ENVIRONMENT_VARIABLE_NAME with the name of a supported environment variable.
   • ENVIRONMENT_VARIABLE_VALUE with the corresponding value for the specified environment variable.

   Example

   [[build.env]]
       name = "GOOGLE_ENTRYPOINT"
       value = "gunicorn -p :8080 main:app"

2. Use gcloud to submit the application source code to Cloud Build:

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/IMAGE_NAME

   Replace:

   • LOCATION with the region name of your container repository. Example: us-west2-docker.pkg.dev
   • PROJECT_ID with the ID of your Google Cloud project.
   • REPO_NAME with the name of your Docker repository.
   • IMAGE_NAME with the name of your container image.

   Examples: If you downloaded a sample application, you run the corresponding command:

   Go

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-go

   Java

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-java-gradle

   Node.js

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-node

   PHP

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-php

   Python

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-python

   Ruby

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-ruby

   .NET

   gcloud builds submit --pack image=LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/sample-dotnet

3. Verify that the sample application was successfully published to REPO_NAME:

   gcloud artifacts docker images list LOCATION-docker.pkg.dev/project-id/REPO_NAME

   Replace:

   • LOCATION with the region name of your container repository. Example: us-west2-docker.pkg.dev
   • PROJECT_ID with the ID of your Google Cloud project.
   • REPO_NAME with the name of your Docker repository.