cloud-foundation-fabric/modules/cloud-function-v2

Cloud Function Module (v2)

Cloud Function management, with support for IAM roles and optional bucket creation.

The GCS object used for deployment uses a hash of the bundle zip contents in its name, which ensures change tracking and avoids recreating the function if the GCS object is deleted and needs recreating.

• TODO
• Examples
  • HTTP trigger
  • PubSub and non-HTTP triggers
  • Controlling HTTP access
  • GCS bucket creation
  • Service account management
  • Custom bundle config
  • Private Cloud Build Pool
  • Multiple Cloud Functions within project
  • Mounting secrets from Secret Manager
• Variables
• Outputs

TODO

• add support for source_repository

Examples

HTTP trigger

This deploys a Cloud Function with an HTTP endpoint, using a pre-existing GCS bucket for deployment, setting the service account to the Cloud Function default one, and delegating access control to the containing project.

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets/"
    output_path = "bundle.zip"
  }
}
# tftest modules=1 resources=2

PubSub and non-HTTP triggers

Other trigger types other than HTTP are configured via the trigger_config variable. This example shows a PubSub trigger via Eventarc:

module "trigger-service-account" {
  source     = "./fabric/modules/iam-service-account"
  project_id = "my-project"
  name       = "sa-cloudfunction"
  iam_project_roles = {
    "my-project" = [
      "roles/run.invoker"
    ]
  }
}

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets/"
    output_path = "bundle.zip"
  }
  trigger_config = {
    event_type            = "google.cloud.pubsub.topic.v1.messagePublished"
    pubsub_topic          = "local.my-topic"
    service_account_email = module.trigger-service-account.email
  }
}
# tftest modules=2 resources=4

Ensure that pubsub service identity (service-[project number]@gcp-sa-pubsub.iam.gserviceaccount.com has roles/iam.serviceAccountTokenCreator as documented here.

Controlling HTTP access

To allow anonymous access to the function, grant the roles/run.invoker role to the special allUsers identifier. Use specific identities (service accounts, groups, etc.) instead of allUsers to only allow selective access. The Cloud Run role needs to be used as explained in the gcloud documentation.

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets/"
    output_path = "bundle.zip"
  }
  iam = {
    "roles/run.invoker" = ["allUsers"]
  }
}
# tftest modules=1 resources=3 inventory=iam.yaml

GCS bucket creation

You can have the module auto-create the GCS bucket used for deployment via the bucket_config variable. Setting bucket_config.location to null will also use the function region for GCS.

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  prefix      = "my-prefix"
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bucket_config = {
    lifecycle_delete_age_days = 1
  }
  bundle_config = {
    source_dir = "fabric/assets/"
  }
}
# tftest modules=1 resources=3 inventory=bucket-creation.yaml

Service account management

To use a custom service account managed by the module, set service_account_create to true and leave service_account set to null value (default).

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets/"
    output_path = "bundle.zip"
  }
  service_account_create = true
}
# tftest modules=1 resources=3

To use an externally managed service account, pass its email in service_account and leave service_account_create to false (the default).

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets/"
    output_path = "bundle.zip"
  }
  service_account = "non-existent@serice.account.email"
}
# tftest modules=1 resources=2

Custom bundle config

In order to help prevent archive_zip.output_md5 from changing cross platform (e.g. Cloud Build vs your local development environment), you'll have to make sure that the files included in the zip are always the same.

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets"
    output_path = "bundle.zip"
    excludes    = ["__pycache__"]
  }
}
# tftest modules=1 resources=2

Private Cloud Build Pool

This deploys a Cloud Function with an HTTP endpoint, using a pre-existing GCS bucket for deployment using a pre existing private Cloud Build worker pool.

module "cf-http" {
  source            = "./fabric/modules/cloud-function-v2"
  project_id        = "my-project"
  region            = var.region
  name              = "test-cf-http"
  bucket_name       = "test-cf-bundles"
  build_worker_pool = "projects/my-project/locations/europe-west1/workerPools/my_build_worker_pool"
  bundle_config = {
    source_dir  = "fabric/assets"
    output_path = "bundle.zip"
  }
}
# tftest modules=1 resources=2

Multiple Cloud Functions within project

When deploying multiple functions do not reuse bundle_config.output_path between instances as the result is undefined. Default output_path creates file in /tmp folder using project Id and function name to avoid name conflicts.

module "cf-http-one" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http-one"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir = "fabric/assets"
  }
}

module "cf-http-two" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http-two"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir = "fabric/assets"
  }
}
# tftest modules=2 resources=4 inventory=multiple_functions.yaml

Mounting secrets from Secret Manager

This provides the latest value of the secret var_secret as VARIABLE_SECRET environment variable and three values of path_secret mounted in filesystem:

• /app/secret/first contains version 1
• /app/secret/second contains version 2
• /app/secret/latest contains latest version of the secret

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v2"
  project_id  = "my-project"
  region      = var.region
  name        = "test-cf-http"
  bucket_name = "test-cf-bundles"
  bundle_config = {
    source_dir  = "fabric/assets"
    output_path = "bundle.zip"
  }
  secrets = {
    VARIABLE_SECRET = {
      is_volume  = false
      project_id = 1234567890
      secret     = "var_secret"
      versions = [
        "latest"
      ]
    }
    "/app/secret" = {
      is_volume  = true
      project_id = 1234567890
      secret     = "path_secret"
      versions = [
        "1:first",
        "2:second",
        "latest:latest"
      ]
    }
  }
}

# tftest modules=1 resources=2 inventory=secrets.yaml

Variables

name	description	type	required	default
bucket_name	Name of the bucket that will be used for the function code. It will be created with prefix prepended if bucket_config is not null.	string	✓
bundle_config	Cloud function source folder and generated zip bundle paths. Output path defaults to '/tmp/bundle.zip' if null.	object({…})	✓
name	Name used for cloud function and associated resources.	string	✓
project_id	Project id used for all resources.	string	✓
region	Region used for all resources.	string	✓
bucket_config	Enable and configure auto-created bucket. Set fields to null to use defaults.	object({…})		null
build_worker_pool	Build worker pool, in projects//locations//workerPools/<POOL_NAME> format.	string		null
description	Optional description.	string		"Terraform managed."
docker_repository_id	User managed repository created in Artifact Registry.	string		null
environment_variables	Cloud function environment variables.	map(string)		{}
function_config	Cloud function configuration. Defaults to using main as entrypoint, 1 instance with 256MiB of memory, and 180 second timeout.	object({…})		{…}
iam	IAM bindings for topic in {ROLE => [MEMBERS]} format.	map(list(string))		{}
ingress_settings	Control traffic that reaches the cloud function. Allowed values are ALLOW_ALL, ALLOW_INTERNAL_AND_GCLB and ALLOW_INTERNAL_ONLY .	string		null
labels	Resource labels.	map(string)		{}
prefix	Optional prefix used for resource names.	string		null
secrets	Secret Manager secrets. Key is the variable name or mountpoint, volume versions are in version:path format.	map(object({…}))		{}
service_account	Service account email. Unused if service account is auto-created.	string		null
service_account_create	Auto-create service account.	bool		false
trigger_config	Function trigger configuration. Leave null for HTTP trigger.	object({…})		null
vpc_connector	VPC connector configuration. Set create to 'true' if a new connector needs to be created.	object({…})		null
vpc_connector_config	VPC connector network configuration. Must be provided if new VPC connector is being created.	object({…})		null

Outputs

name	description	sensitive
bucket	Bucket resource (only if auto-created).
bucket_name	Bucket name.
function	Cloud function resources.
function_name	Cloud function name.
id	Fully qualified function id.
service_account	Service account resource.
service_account_email	Service account email.
service_account_iam_email	Service account email.
trigger_service_account	Service account resource.
trigger_service_account_email	Service account email.
trigger_service_account_iam_email	Service account email.
uri	Cloud function service uri.
vpc_connector	VPC connector resource if created.