Using Google Cloud Deploy execution environments

A Google Cloud Deploy execution environment is the environment in which Google Cloud Deploy executes its render and deploy operations. The execution environment consists of the following:

The Cloud Build worker pool (default or private) in which Google Cloud Deploy executes render and deploy operations.
The service account (default or alternate) that calls Google Cloud Deploy to perform these actions.
The storage location (default or alternate) for rendered manifests in Cloud Storage.

This article describes the default execution environment, service accounts, and storage for Google Cloud Deploy, as well as why and how you can change these defaults.

Defaults

The following are the defaults that Google Cloud Deploy uses to run, to execute rendering and deployment, and to store assets such as rendered manifests:

Default worker pool

By default, Google Cloud Deploy runs in the default Cloud Build worker pool. However, you can configure Google Cloud Deploy to use a Cloud Build private worker pool.

For more details about worker pools, see the Cloud Build Overview of default pools and private pools.
Default execution service account

By default, Google Cloud Deploy uses the default Compute Engine service account.
Default Google Cloud Deploy storage location

This value is the Cloud Storage bucket where Google Cloud Deploy stores your rendered manifests. By default, Google Cloud Deploy creates a Cloud Storage bucket, in the same region as the Google Cloud Deploy resources, taking the following form:

<location>.deploy-artifacts.<project ID>.appspot.com

The sections that follow describe the circumstances under which you would change any of these values, and links to instructions for doing so.

About the default and private worker pools

The default execution environment is the Cloud Build default pool. This default worker pool is a secure, hosted environment with access to the public internet. Render and deploy operations are executed in that pool, isolated from other workloads.

Private worker pools are private, dedicated pools that can be customized more than the default worker pool. That customization can include the ability to access resources in a private network.

Like the default worker pool, private worker pools are hosted and fully managed by Cloud Build. These pools can scale up or scale down to zero, with no infrastructure to set up, upgrade, or scale.

The Cloud Build Private pools overview describes default worker pools and private worker pools more thoroughly, including a table comparing their features.

Changing the Google Cloud Deploy execution environment

You might change the Google Cloud Deploy execution environment under the following circumstances:

You want to deploy to a private Google Kubernetes Engine cluster
You want render or deploy operations, or both, to be performed in an environment that is isolated from other organizations.
You want these operations to be performed in an environment that is not connected to the public internet.
You want separate environments for render and deploy.
You want to use a dedicated service account with permissions that are more specific to your use than the permissions available in the default service account.
You want to store rendered manifests in a location different from the default Cloud Storage bucket.

Configuration of all three parts of the execution environment (worker pool, service account, and storage) is done per target, in each target's YAML configuration.

Changing from the default pool to a private pool

You configure worker pools per target, so that the pool is used for RENDER or DEPLOY (or both) for that target only.

To use the default worker pool for both render and deploy operations, you don't need to do anything.

The following is a sample target configuration that specifies a private worker pool for DEPLOY and the default worker pool for RENDER:

     executionConfigs:
     - privatePool:
       workerPool: "projects/p123/locations/us-central1/workerPools/wp123"
        usages:
        - DEPLOY
     - defaultPool:
        usages:
        - RENDER

For more information about how to configure private pools for targets, see Delivery pipeline configuration documentation.

Changing from the default to custom execution service account

As with the worker pool, you can specify an alternate service account to use for rendering or deploying (or both) per target. To do so, add the following line to the target configuration, after the workerPool element:

serviceAccount: "[name]@[project_name].iam.googleapis.com"

The specified service account must include the clouddeploy.jobRunner role, as described in the Google Cloud Deploy service accounts document.

See Target definitions for more details on this configuration.

Changing the storage location

To change the storage bucket from the Google Cloud Deploy default, add the following line to the target definition in the privatePool or defaultPool stanza:

artifactStorage: "gs://[bucket_name]/[dir]"

This configuration changes where the rendered manifests are stored, but does not affect where the rendering source is stored.

Deploying to a private cluster on a Virtual Private Cloud network

You can configure a target to deploy to a private GKE cluster connected to a Virtual Private Cloud network:

Create your private cluster

A private cluster is a VPC-native cluster whose nodes and Pods are isolated by default from the public internet.
In Cloud Build, create a private worker pool that you can use to deploy to this private cluster.
Configure the execution environment to use that private pool.

You must use this pool for RENDER. You can also use it for DEPLOY. Here's an example that uses both:
```
executionConfigs:
- privatePool:
workerPool: "projects/p123/locations/us-central1/workerPools/wp123"
 usages:
 - RENDER
 - DEPLOY
```

See Accessing private GKE clusters with Cloud Build private pools for more information.

Project and permissions considerations

It's simple to configure a target to use a private worker pool that can deploy to a private cluster. But there are some things to note if resources are in different projects.

When Google Cloud Deploy and the worker pool are in separate projects

To communicate with a private pool that has access to a VPC and that's in a different project from your target, the Google Cloud Deploy service agent needs sufficient permissions to talk to that project.

The execution service account also needs permissions to access the Cloud Storage bucket.

When the worker pool and the cluster are in separate projects

If the private GKE cluster is in a different project from the private worker pool, the execution service account requires sufficient permissions to talk to the project the cluster is in.

VPC-SC considerations

Google Cloud Deploy does not support VPC Service Controls. However, Google Cloud Deploy relies on Cloud Build for rendering and deploying. Using VPC-SC to protect resources or operations in Cloud Build can have implications for any worker pool you configure for your execution environment.

For example, the project that contains the worker pool and the project that contains your Google Cloud Deploy resources must be inside the same VPC Service Controls security perimeter.

What's next

Find out more about Google Cloud Deploy target configuration.
Read about Cloud Build private pools.
Learn about how Google Cloud Deploy uses service accounts.
Access private GKE clusters with Cloud Build private pools.