README.md

Cloud Function Module (V1)

Cloud Function management, with support for IAM roles, optional bucket creation and bundle via GCS URI, local zip, or local source folder.

• 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
  • Using CMEK to encrypt function resources
• Variables
• Outputs
• Fixtures

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-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
}
# tftest modules=1 resources=5   fixtures=fixtures/functions-default-sa-iam-grants.tf e2e

PubSub and non-HTTP triggers

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

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
  trigger_config = {
    event    = "google.pubsub.topic.publish"
    resource = module.pubsub.topic.name
  }
}
# tftest modules=2 resources=7 fixtures=fixtures/pubsub.tf,fixtures/functions-default-sa-iam-grants.tf e2e

Controlling HTTP access

To allow anonymous access to the function, grant the roles/cloudfunctions.invoker role to the special allUsers identifier. Use specific identities (service accounts, groups, etc.) instead of allUsers to only allow selective access.

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
  iam = {
    "roles/cloudfunctions.invoker" = ["allUsers"]
  }
}
# tftest modules=1 resources=6 fixtures=fixtures/functions-default-sa-iam-grants.tf inventory=iam.yaml e2e

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-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  prefix      = var.prefix
  name        = "test-cf-http"
  bucket_name = var.bucket
  bucket_config = {
    force_destroy             = true
    lifecycle_delete_age_days = 1
  }
  bundle_config = {
    path = "assets/sample-function/"
  }
}
# tftest modules=1 resources=6 fixtures=fixtures/functions-default-sa-iam-grants.tf inventory=bucket-creation.yaml e2e

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-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
  service_account_create = true
}
# tftest modules=1 resources=6 fixtures=fixtures/functions-default-sa-iam-grants.tf e2e

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-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
  service_account = var.service_account.email
}
# tftest modules=1 resources=5 fixtures=fixtures/functions-default-sa-iam-grants.tf e2e

Custom bundle config

The Cloud Function bundle can be configured via the bundle_config variable. The only mandatory argument is bundle_config.path which can point to:

• a GCS URI of a ZIP archive
• a local path to a ZIP archive
• a local path to a source folder

When a GCS URI or a local zip file are used, a change in their names will trigger redeployment. When a local source folder is used a ZIP archive will be automatically generated and its internally derived checksum will drive redeployment. You can optionally control its name and exclusions via the attributes in bundle_config.folder_options.

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
    folder_options = {
      archive_path = "bundle.zip"
      excludes     = ["__pycache__"]
    }
  }
}
# tftest modules=1 resources=5 fixtures=fixtures/functions-default-sa-iam-grants.tf  e2e

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-v1"
  project_id        = var.project_id
  region            = var.regions.secondary
  name              = "test-cf-http"
  bucket_name       = var.bucket
  build_worker_pool = google_cloudbuild_worker_pool.pool.id
  bundle_config = {
    path = "assets/sample-function/"
  }
}
# tftest modules=1 resources=6 fixtures=fixtures/cloudbuild-custom-pool.tf,fixtures/functions-default-sa-iam-grants.tf e2e

Multiple Cloud Functions within project

When deploying multiple functions do not reuse bundle_config.archive_path between instances as the result is undefined. Default archive_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-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http-one"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
}

module "cf-http-two" {
  source      = "./fabric/modules/cloud-function-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http-two"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
}
# tftest modules=2 resources=7 fixtures=fixtures/functions-default-sa-iam-grants.tf inventory=multiple_functions.yaml e2e

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/ver1 contains version referenced by module.secret-manager.version_versions["credentials:v1"]

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
  secrets = {
    VARIABLE_SECRET = {
      is_volume  = false
      project_id = var.project_number # use project_number  to avoid perm-diff
      secret     = reverse(split("/", module.secret-manager.secrets["credentials"].name))[0]
      versions = [
        "latest"
      ]
    }
    "/app/secret" = {
      is_volume  = true
      project_id = var.project_number # use project_number  to avoid perm-diff
      secret     = reverse(split("/", module.secret-manager.secrets["credentials"].name))[0]
      versions = [
        "${module.secret-manager.version_versions["credentials:v1"]}:/ver1"
      ]
    }
  }
}
# tftest modules=2 resources=8 fixtures=fixtures/secret-credentials.tf,fixtures/functions-default-sa-iam-grants.tf  inventory=secrets.yaml e2e

Using CMEK to encrypt function resources

This encrypt bucket gcf-sources-* with the provided kms key. The repository has to be encrypted with the same kms key.

module "kms" {
  source     = "./fabric/modules/kms"
  project_id = var.project_id
  keyring = {
    location = var.regions.secondary
    name     = "function-cmek"
  }
  keys = {
    "key" = {}
  }
  iam = {
    "roles/cloudkms.cryptoKeyEncrypterDecrypter" = [
      "serviceAccount:service-${var.project_number}@gcf-admin-robot.iam.gserviceaccount.com",
      "serviceAccount:service-${var.project_number}@gcp-sa-artifactregistry.iam.gserviceaccount.com",
      "serviceAccount:service-${var.project_number}@gs-project-accounts.iam.gserviceaccount.com",
    ]
  }
}

module "artifact-registry" {
  source         = "./fabric/modules/artifact-registry"
  project_id     = var.project_id
  location       = var.regions.secondary
  name           = "registry"
  format         = { docker = { standard = {} } }
  encryption_key = module.kms.key_ids["key"]
  depends_on = [
    module.kms
  ]
}

module "cf-http" {
  source      = "./fabric/modules/cloud-function-v1"
  project_id  = var.project_id
  region      = var.regions.secondary
  name        = "test-cf-http"
  bucket_name = var.bucket
  bundle_config = {
    path = "assets/sample-function/"
  }
  kms_key = module.kms.key_ids["key"]
  repository_settings = {
    repository = module.artifact-registry.id
  }
}
# tftest modules=3 resources=9 fixtures=fixtures/functions-default-sa-iam-grants.tf e2e

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. Path can point to a GCS object URI, or a local path. A local path to a zip archive will generate a GCS object using its basename, a folder will be zipped and the GCS object name inferred when not specified.	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_environment_variables	A set of key/value environment variable pairs available during build time.	map(string)		{}
build_worker_pool	Build worker pool, in projects//locations//workerPools/<POOL_NAME> format.	string		null
description	Optional description.	string		"Terraform managed."
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({…})		{…}
https_security_level	The security level for the function: Allowed values are SECURE_ALWAYS, SECURE_OPTIONAL.	string		null
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
kms_key	Resource name of a KMS crypto key (managed by the user) used to encrypt/decrypt function resources in key id format. If specified, you must also provide an artifact registry repository using the docker_repository field that was created with the same KMS crypto key.	string		null
labels	Resource labels.	map(string)		{}
prefix	Optional prefix used for resource names.	string		null
repository_settings	Docker Registry to use for storing the function's Docker images and specific repository. If kms_key is provided, the repository must have already been encrypted with the key.	object({…})		{…}
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.
vpc_connector	VPC connector resource if created.

Fixtures

• cloudbuild-custom-pool.tf
• functions-default-sa-iam-grants.tf
• pubsub.tf
• secret-credentials.tf