Variables and outputs in GCP - Mini Project: Build & Apply

Using Variables and Outputs in GCP Deployment Manager

📖 Scenario: You are setting up a simple Google Cloud Platform (GCP) deployment using Deployment Manager. You want to create a virtual machine instance with a specific name and zone, and then output the instance's selfLink URL after deployment.

🎯 Goal: Build a Deployment Manager configuration that uses variables to define the VM instance name and zone, and outputs the instance's selfLink URL.

📋 What You'll Learn

Create a variable called instanceName with the value my-vm-instance.

Create a variable called zone with the value us-central1-a.

Define a resource of type compute.v1.instance using the variables for name and zone.

Add an output called instanceSelfLink that outputs the selfLink of the created instance.

💡 Why This Matters

🌍 Real World

Cloud engineers often use Deployment Manager to automate creating and managing cloud resources with reusable templates.

💼 Career

Knowing how to use variables and outputs in cloud templates is essential for infrastructure as code roles and cloud automation tasks.

1

Create variables for instance name and zone

Create a variable called instanceName and set it to my-vm-instance. Also create a variable called zone and set it to us-central1-a.

GCP

# Define variables for instance name and zone
# Your code here

Need a hint?

Use YAML syntax to define variables with exact names and values.

2

Add a resource using the variables

Add a resource named vm-instance of type compute.v1.instance. Use the variables instanceName for the resource name and zone for the resource zone property.

GCP

instanceName: my-vm-instance
zone: us-central1-a

# Add resource vm-instance using instanceName and zone variables
# Your code here

Need a hint?

Use $(variableName) syntax to reference variables inside properties.

3

Add an output for the instance selfLink

Add an output called instanceSelfLink that outputs the selfLink of the resource named vm-instance.

GCP

instanceName: my-vm-instance
zone: us-central1-a

resources:
- name: vm-instance
  type: compute.v1.instance
  properties:
    zone: $(zone)
    name: $(instanceName)
    machineType: zones/$(zone)/machineTypes/f1-micro
    disks:
    - deviceName: boot
      type: PERSISTENT
      boot: true
      autoDelete: true
      initializeParams:
        sourceImage: projects/debian-cloud/global/images/family/debian-11
    networkInterfaces:
    - network: global/networks/default

# Add output instanceSelfLink here
# Your code here

Need a hint?

Outputs use $(ref.resourceName.property) syntax to get resource properties.

4

Complete the deployment configuration

Ensure the deployment configuration includes the variables instanceName and zone, the resource vm-instance using those variables, and the output instanceSelfLink with the correct reference.

GCP

instanceName: my-vm-instance
zone: us-central1-a

resources:
- name: vm-instance
  type: compute.v1.instance
  properties:
    zone: $(zone)
    name: $(instanceName)
    machineType: zones/$(zone)/machineTypes/f1-micro
    disks:
    - deviceName: boot
      type: PERSISTENT
      boot: true
      autoDelete: true
      initializeParams:
        sourceImage: projects/debian-cloud/global/images/family/debian-11
    networkInterfaces:
    - network: global/networks/default

outputs:
- name: instanceSelfLink
  value: $(ref.vm-instance.selfLink)

# Review and finalize your configuration
# Your code here

Need a hint?

Check that all parts are present and correctly linked.