Cloud Deployment Manager

Google Cloud Deployment Manager is Google's native Infrastructure as Code (IaC) service. It allows you to define, deploy, and manage Google Cloud resources using declarative YAML configuration files and templates. Deployment Manager treats infrastructure as repeatable, version-controlled code — eliminating manual resource creation and reducing configuration drift.

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What Is Deployment Manager?

Deployment Manager is a fully managed service that automates the creation and management of Google Cloud resources. You describe the desired state of your infrastructure in configuration files, and Deployment Manager creates, updates, or deletes resources to match that state.

Key Characteristics

Characteristic	Description
Declarative	Define what you want, not how to create it
Repeatable	Deploy the same configuration to multiple projects or environments
Idempotent	Running the same deployment twice produces the same result
Preview	Preview changes before applying them
Parallel	Creates independent resources in parallel for faster deployments
Integrated	Native to GCP — no additional tools to install

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Core Concepts

Configurations

A configuration is a YAML file that describes the resources you want to create. Each resource has a name, a type, and properties:

resources:
- name: my-vm
  type: compute.v1.instance
  properties:
    zone: europe-west1-b
    machineType: zones/europe-west1-b/machineTypes/e2-medium
    disks:
    - boot: true
      autoDelete: true
      initializeParams:
        sourceImage: projects/debian-cloud/global/images/family/debian-11
    networkInterfaces:
    - network: global/networks/default
      accessConfigs:
      - name: External NAT
        type: ONE_TO_ONE_NAT

Resource Types

Deployment Manager supports all Google Cloud resource types. Each type corresponds to a GCP API resource:

Type	Example
Compute	compute.v1.instance, compute.v1.network
Storage	storage.v1.bucket
SQL	sqladmin.v1beta4.instance
Pub/Sub	pubsub.v1.topic, pubsub.v1.subscription
IAM	iam.v1.serviceAccount
GKE	container.v1.cluster

Deployments

A deployment is a collection of resources managed together. When you create a deployment, Deployment Manager provisions all the resources defined in the configuration:

# Create a deployment
gcloud deployment-manager deployments create my-deployment \
  --config=config.yaml

# Update a deployment
gcloud deployment-manager deployments update my-deployment \
  --config=config-v2.yaml

# Preview changes before applying
gcloud deployment-manager deployments update my-deployment \
  --config=config-v2.yaml \
  --preview

# Apply the previewed changes
gcloud deployment-manager deployments update my-deployment

# Delete a deployment (deletes all managed resources)
gcloud deployment-manager deployments delete my-deployment

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Templates

Templates make configurations reusable and parameterisable. Deployment Manager supports two template formats:

Jinja2 Templates

{# vm-template.jinja #}
resources:
- name: {{ env["name"] }}
  type: compute.v1.instance
  properties:
    zone: {{ properties["zone"] }}
    machineType: zones/{{ properties["zone"] }}/machineTypes/{{ properties["machineType"] }}
    disks:
    - boot: true
      autoDelete: true
      initializeParams:
        sourceImage: {{ properties["sourceImage"] }}
    networkInterfaces:
    - network: global/networks/default

Python Templates

Python templates provide more flexibility with logic, loops, and conditionals:

# vm-template.py
def GenerateConfig(context):
    resources = []
    for i in range(context.properties['count']):
        resources.append({
            'name': f'{context.env["name"]}-{i}',
            'type': 'compute.v1.instance',
            'properties': {
                'zone': context.properties['zone'],
                'machineType': f'zones/{context.properties["zone"]}/machineTypes/{context.properties["machineType"]}',
                'disks': [{
                    'boot': True,
                    'autoDelete': True,
                    'initializeParams': {
                        'sourceImage': context.properties['sourceImage'],
                    },
                }],
                'networkInterfaces': [{
                    'network': 'global/networks/default',
                }],
            },
        })
    return {'resources': resources}

Using Templates

Reference templates from your configuration file:

imports:
- path: vm-template.jinja

resources:
- name: web-server
  type: vm-template.jinja
  properties:
    zone: europe-west1-b
    machineType: e2-medium
    sourceImage: projects/debian-cloud/global/images/family/debian-11

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Schema Files

Schema files validate template properties and provide documentation:

# vm-template.jinja.schema
info:
  title: VM Instance Template
  description: Creates a Compute Engine VM instance

required:
  - zone
  - machineType
  - sourceImage

properties:
  zone:
    type: string
    description: The GCP zone for the instance
  machineType:
    type: string
    description: The machine type (e.g., e2-medium)
    default: e2-small
  sourceImage:
    type: string
    description: The source image for the boot disk

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Managing Dependencies

Deployment Manager automatically detects dependencies between resources. You can also define explicit dependencies using the metadata.dependsOn field:

resources:
- name: my-network
  type: compute.v1.network
  properties:
    autoCreateSubnetworks: false

- name: my-subnet
  type: compute.v1.subnetwork
  properties:
    network: $(ref.my-network.selfLink)
    ipCidrRange: 10.0.0.0/24
    region: europe-west1

- name: my-vm
  type: compute.v1.instance
  metadata:
    dependsOn:
    - my-subnet
  properties:
    zone: europe-west1-b
    machineType: zones/europe-west1-b/machineTypes/e2-medium
    networkInterfaces:
    - subnetwork: $(ref.my-subnet.selfLink)

The $(ref.resource-name.property) syntax creates references between resources, which also establishes implicit dependencies.

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Limitations and Considerations

Limitation	Description
GCP only	Only manages Google Cloud resources
State management	State is managed by the service — no remote state configuration
No import	Cannot import existing resources into a deployment
Template language	Limited to Jinja2 and Python (no HCL, TypeScript, etc.)
Community	Smaller community compared to Terraform

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Summary

Cloud Deployment Manager is Google Cloud's native IaC tool for defining and managing infrastructure as code. It uses declarative YAML configurations with Jinja2 or Python templates for reusability. While it integrates seamlessly with GCP, its scope is limited to Google Cloud resources. For multi-cloud environments or teams already using Terraform, Deployment Manager may not be the best fit — but for GCP-only projects, it provides a straightforward, fully managed IaC experience with no additional tooling required. In the next lesson, we will explore Terraform on GCP, which offers multi-cloud support and a larger ecosystem.