Build functions

You can build Cloud Run functions using Google Cloud's buildpacks.

This page shows you two ways to build your functions for deployment into Cloud Run:

Using pack CLI
Using Cloud Build as the remote build system

Function Entry Point

To build functions with buildpacks:

Include the Functions Framework library.
Set the GOOGLE_FUNCTION_TARGET environment variable to the name of the function that you use as the entrypoint. You can do this by including a project.toml in the same folder as your source code. The project.toml file must have the following configuration:

[[build.env]]
    name = "GOOGLE_FUNCTION_TARGET"
    value =  "ENTRY_POINT"

Replace ENTRY_POINT with the function method.

For details about how to use environment variables with Cloud Run functions, see Configure Cloud Run functions services.

Builders

Cloud Run functions are built on top of base images maintained and published under Google Cloud's buildpacks.

Builders are images that consist of buildpacks and operating system packages (also known as Stacks). Builders are used to convert your function's source code into a running container.

You can choose from the list of supported Google Cloud's buildpacks builders.

Building with `pack`

Pack is a CLI tool maintained by the CNB project to support the use of buildpacks. Use the pack CLI to locally build your functions into a container image.

Before you begin

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

Build a function locally

You use the pack build command and specify the default builder --builder=gcr.io/buildpacks/builder to build your container images locally.

pack build --builder=gcr.io/buildpacks/builder IMAGE_NAME

Replace IMAGE_NAME with the name of your container image.

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

Build a sample function locally

The following examples demonstrate how to build a sample locally.

Clone the sample repository to your local machine:

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

Change to the directory that contains the application sample code:

Go

cd buildpack-samples/sample-functions-framework-go

Java

cd buildpack-samples/sample-functions-framework-java-mvn

Node.js

cd buildpack-samples/sample-functions-framework-node

Python

cd buildpack-samples/sample-functions-framework-python

Ruby

cd buildpack-samples/sample-functions-framework-ruby

Use pack to build the sample function:

Go

pack build --builder=gcr.io/buildpacks/builder sample-functions-framework-go

Java

pack build --builder gcr.io/buildpacks/builder:v1 sample-functions-java-mvn

Node.js

pack build --builder=gcr.io/buildpacks/builder sample-functions-framework-node

Python

pack build --builder=gcr.io/buildpacks/builder sample-functions-framework-python

Ruby

pack build --builder=gcr.io/buildpacks/builder sample-functions-framework-ruby

Run the image using docker:

Go

docker run -p8080:8080 sample-functions-framework-go

Java

docker run -it -ePORT=8080 -p8080:8080 sample-functions-java-mvn

Node.js

docker run -it -ePORT=8080 -p8080:8080 sample-functions-framework-node

Python

docker run -it -ePORT=8080 -p8080:8080 sample-functions-framework-python

Ruby

docker run -it -ePORT=8080 -p8080:8080 sample-functions-framework-ruby

Visit the running function by browsing to localhost:8080.

Building with a remote build system

Use Cloud Build to build your function into a container image, and Artifact Registry as the container repository to store and deploy each image.

Before you begin

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.

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

Go to project selector

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

Enable the Cloud Build and Artifact Registry APIs.

Enable the APIs

Install the Google Cloud CLI.

To initialize the gcloud CLI, run the following command:

gcloud init

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

Go to project selector

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

Enable the Cloud Build and Artifact Registry APIs.

Enable the APIs

Install the Google Cloud CLI.

To initialize the gcloud CLI, run the following command:

gcloud init

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.

Build a function remotely

You use the gcloud builds submit command to build and upload your container image to your repository.

You can choose to specify your container image in the command itself or use a configuration file.

Build with command

To build without a configuration file, specify the image flag:

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, for example, us-west2
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.

Example:

gcloud builds submit --pack image=us-west2-docker.pkg.dev/my-project-id/my-buildpacks-docker-repo

Build with configuration files

You can use a configuration file to define your image repository configuration details to simply the build command. The configuration file uses the YAML file format and must include a build step that uses the pack CLI.

Create a YAML file name cloudbuild.yaml that includes the URI of your container image repository.

  options:
    logging: CLOUD_LOGGING_ONLY
    pool: {}
  projectId: PROJECT_ID
  steps:
  - name: gcr.io/k8s-skaffold/pack
    entrypoint: pack
    args:
    - build
    - LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/IMAGE_NAME
    - --builder
    - gcr.io/buildpacks/builder:latest
    - --network
    - cloudbuild
  images:
  - LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/IMAGE_NAME

Replace:

LOCATION with the region name of your container repository, for example, us-west2.
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.

Build the application.

If you named your configuration file cloudbuild.yaml, you can run the following command:
```
gcloud builds submit .
```
Tip: If you use a unique name for your configuration file, you can use the --config flag.

Example: Build a sample function remotely

The following examples demonstrate how to build a sample remotely, and verify that the container image was pushed to your repository in Artifact Registry.

Clone the sample repository to your local machine:

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

Change to the directory that contains the application sample code:

Go

cd buildpack-samples/sample-functions-framework-go

Java

cd buildpack-samples/sample-functions-framework-java-mvn

Node.js

cd buildpack-samples/sample-functions-framework-node

Python

cd buildpack-samples/sample-functions-framework-python

Ruby

cd buildpack-samples/sample-functions-framework-ruby

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

Go

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

Java

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

Node.js

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

Python

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

Ruby

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

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.

Verify that the sample function was successfully published into 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, for example, us-west2.
- PROJECT_ID with the ID of your Google Cloud project.
- REPO_NAME with the name of your Docker repository.

Building a function for automatic base image updates

Function containers can also be built on scratch, allowing them to be used in combination with Cloud Run automatic security updates.

`pack` CLI

pack build IMAGE_NAME \
  --builder LOCATION.pkg.dev/serverless-runtimes/google-22-full/builder/LANGUAGE:latest
  --run-image LOCATION-docker.pkg.dev/serverless-runtimes/google-22/scratch/RUNTIME_ID:latest

Replace:

LOCATION with the region name of your container repository, for example, us-west2.
IMAGE_NAME with the name of your container image.
LANGUAGE with the language of your function, for example nodejs.
RUNTIME_ID with the runtime ID, for example nodejs22.

Cloud Build

options:
  logging: CLOUD_LOGGING_ONLY
  pool: {}
projectId: PROJECT_ID
steps:
- name: gcr.io/k8s-skaffold/pack
  entrypoint: pack
  args:
  - build
  - LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/IMAGE_NAME
  - --builder
  - LOCATION-docker.pkg.dev/serverless-runtimes/google-22-full/builder/LANGUAGE:latest
  - --run-image
  - LOCATION-docker.pkg.dev/serverless-runtimes/google-22/scratch/RUNTIME_ID:latest
  - --network
  - cloudbuild
images:
- LOCATION-docker.pkg.dev/PROJECT_ID/REPO_NAME/IMAGE_NAME

Replace:

LOCATION with the region name of your container repository, for example, us-west2.
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.
LANGUAGE with the language of your function, for example nodejs.
RUNTIME_ID with the runtime ID, for example nodejs22.

What's next?

After you build your container, test it locally before deploying to Cloud Run. See Testing a Cloud Run service locally to learn more.
To understand key requirements and behaviors of containers in Cloud Run, see Container contract.
To deploy your built containers to Cloud Run, follow Deploying services.
To automate the builds and deployments of your Cloud Run services using Cloud Build triggers, see set up continuous deployment.
To perform optimal container builds for Java application, see Building Java containers with Jib.

Build functions

Function Entry Point

Builders

Building with pack

Before you begin

Build a function locally

Build a sample function locally

Go

Java

Node.js

Python

Ruby

Go

Java

Node.js

Python

Ruby

Go

Java

Node.js

Python

Ruby

Building with a remote build system

Before you begin

Build a function remotely

Build with command

Build with configuration files

Example: Build a sample function remotely

Go

Java

Node.js

Python

Ruby

Go

Java

Node.js

Python

Ruby

Building a function for automatic base image updates

pack CLI

Cloud Build

What's next?

Building with `pack`

`pack` CLI