Build and test Go applications

This page explains how to use Cloud Build to build and test your Go applications, upload your artifacts to Artifact Registry, generate provenance information, and save your test logs in Cloud Storage.

Before you begin

The instructions on this page assume that you are familiar with Go. In addition:

  • Enable the Cloud Build, Cloud Run, and Artifact Registry APIs.

    Roles required to enable APIs

    To enable APIs, you need the Service Usage Admin IAM role (roles/serviceusage.serviceUsageAdmin), which contains the serviceusage.services.enable permission. Learn how to grant roles.

    Enable the APIs

  • To run the gcloud commands on this page, install Google Cloud CLI.
  • Have your Go project ready.
  • Have a Go repository in Artifact Registry. If you don't have one, then create a new repository.
  • If you want to store test logs in Cloud Storage, then create a bucket in Cloud Storage.
  • Ensure that you know the ID of the runtime service account for Cloud Run.

Create a custom Cloud Build service account

Create a custom Cloud Build service account by running the following command in Google Cloud CLI:

  gcloud iam service-accounts create cloud-build-go \
  --description="Build and test Go applications" \
  --display-name="Cloud Build Go" \
  --project="PROJECT_NAME"

You will use this service account to build and test your Go application.

Configure IAM permissions

To configure your new service account with the permissions required to build and deploy Go applications, do the following:

  1. In the Google Cloud console, go to the Cloud Build Permissions page:

    Go to Permissions

  2. Go to the Service account menu and select your cloud-build-go service account.

  3. Set the status of the following roles to Enabled:

    • Cloud Run Admin (roles/run.admin): Lets Cloud Build deploy new services to Cloud Run.
    • Storage Admin (roles/storage.admin): Enables reading and writing from Cloud Storage.
    • Artifact Registry Writer (roles/artifactregistry.writer): Allows pulling images from and writing to Artifact Registry.
    • Logs Writer (roles/logging.logWriter): Allows log entries to be written to Cloud Logging.
    • Cloud Build Editor (roles/cloudbuild.builds.editor): Allows your service account to run builds.

Configure Go builds

The public golang image from Docker Hub supports building using Go modules. Using this image as a build step in your Cloud Build config file lets you invoke go commands within the image. Arguments passed to this build step are passed to the golang tool directly, allowing you to run any go command in this image.

This section shows how to create an example build config file for a Go app from the cloud-build-samples Git repository. The build config file has steps to build the app, add unit tests, and after the tests pass, to deploy the app.

To build the example Go application:

  1. Configure unit tests: If you've defined unit tests in your application, you can configure Cloud Build to run the tests by adding the following fields in a build step:

    • name: Set the value of this field to golang to use the golang image from Docker Hub for your task.
    • entrypoint: Set the value of this field to /bin/bash. This lets you run multi-line bash commands directly from the build step.

    • args: The args field of a build step takes a list of arguments and passes them to the image referenced by the name field. In the following example, the args field takes the arguments for:

      • Running the test log formatter to download the test log output.
      • Printing the log output.
      • Saving test results in sponge.log.

      • Outputting the results in sponge.log to a JUNIT XML file. The name of the JUNIT XML file is constructed using the short version of the commit ID associated with your build. A subsequent build step will save the logs in this file to Cloud Storage.

        steps:
  # Run tests and save to file
  - name: golang:1.23
    entrypoint: /bin/bash
    args:
      - -c
      - |
        go install github.com/jstemmer/go-junit-report/v2@latest
        2>&1 go test -timeout 1m -v ./... | /go/bin/go-junit-report -set-exit-code -iocopy -out ${SHORT_SHA}_test_log.xml

  2. Upload to Artifact Registry: In your config file, use the goModules field to specify your application path and your Go repository in Artifact Registry:

    # Upload Go module to artifact registry
artifacts:
  goModules:
    - repositoryName: 'repositoryName'
      repositoryLocation: 'location'
      repositoryProjectId: 'projectId'
      sourcePath: 'sourcePath'
      modulePath: 'appPath'
      moduleVersion: 'version'

    Replace the following values:

    • repositoryName: the name of your Go repository in Artifact Registry.
    • location: the location for your repository in Artifact Registry.
    • projectId: the ID of the Google Cloud project that contains your Artifact Registry repository.
    • sourcePath: the path to the go.mod file in the build's workspace.
    • appPath: the path to your packaged application.
    • version: the version number for your application, formatted in numbers and dots like v1.0.1.

  3. Optional: Enable provenance generation

    Cloud Build can generate verifiable Supply chain Levels for Software Artifacts (SLSA) build provenance metadata to help secure your continuous integration pipeline.

    To enable provenance generation, add requestedVerifyOption: VERIFIED to the options section in your config file.

    Once your build completes, you can view repository details in Artifact Registry.

    You can also view build provenance metadata and validate provenance.

  4. Save test logs to Cloud Storage: You can configure Cloud Build to store any test logs in Cloud Storage by specifying an existing bucket location and path to the test logs.

    The following build step stores the test logs that you saved in the JUNIT XML file to a Cloud Storage bucket:

    # Save test logs to Google Cloud Storage
artifacts:
  objects:
    location: gs://$_BUCKET_NAME/
    paths:
      - ${SHORT_SHA}_test_log.xml

    The following snippet shows the complete build config file for the preceding steps:

      steps:
    # Run tests and save to file
    - name: golang:1.23
      entrypoint: /bin/bash
      args:
        - -c
        - |
          go install github.com/jstemmer/go-junit-report/v2@latest
          2>&1 go test -timeout 1m -v ./... | /go/bin/go-junit-report -set-exit-code -iocopy -out ${SHORT_SHA}_test_log.xml

  # Store golang modules in Google Artifact Registry
  artifacts:
    goModules:
      - repositoryName: 'repositoryName'
        repositoryLocation: 'location'
        repositoryProjectId: 'projectId'
        sourcePath: 'sourcePath'
        modulePath: 'appPath'
        moduleVersion: 'version'

  5. Start the build using the gcloud CLI or create a build trigger:

Google Cloud CLI 

 gcloud builds submit --region=us-west2 --config=cloudbuild.yaml \
     --substitutions=_AR_REPO_NAME="AR_REPO_NAME"

Build Triggers

Follow the steps in Create a build trigger. In the Substitution variables field, you must also provide the name of your Artifact Registry repository and the name of your Cloud Storage bucket for test logs.

What's next