Deploying Serverless Functions with Terraform on Google Cloud

In today’s cloud-native world, serverless computing has gained significant traction, enabling developers to focus on writing code without worrying about managing the underlying infrastructure. Google Cloud Platform (GCP) offers a powerful serverless solution through Google Cloud Functions. Coupled with Terraform, an Infrastructure as Code (IaC) tool, deploying serverless functions becomes streamlined and efficient. In this article, we’ll explore how to deploy serverless functions with Terraform on Google Cloud, covering essential concepts, use cases, and step-by-step instructions.

What Are Serverless Functions?

Serverless functions allow developers to run code in response to events without provisioning or managing servers. This model offers several benefits:

• Scalability: Automatically scales with demand.
• Cost-efficient: Pay only for the resources consumed during execution.
• Reduced Operational Overhead: Focus on writing code rather than managing infrastructure.

Use Cases for Serverless Functions

Serverless functions can be used in various scenarios, including:

• API Backends: Create RESTful APIs that respond to HTTP requests.
• Data Processing: Process data in real-time as it is ingested into cloud storage.
• Event-Driven Architectures: Respond to events from Google Cloud services like Pub/Sub or Cloud Storage.

Why Use Terraform?

Terraform is an open-source IaC tool that allows you to define and provision your infrastructure using a declarative configuration language. Key benefits of using Terraform include:

• Version Control: Track infrastructure changes over time.
• Collaboration: Share configurations with team members.
• Automation: Automate the deployment process, reducing manual errors.

Getting Started: Prerequisites

Before we dive into deploying serverless functions, ensure you have the following:

1. Google Cloud Account: Sign up for a Google Cloud account.
2. Terraform Installed: Download and install Terraform from the official website.
3. Google Cloud SDK: Install the Google Cloud SDK.
4. Basic Knowledge of Terraform: Familiarity with Terraform syntax and concepts.

Step-by-Step Guide to Deploying Serverless Functions

Step 1: Create a Google Cloud Project

1. Go to the Google Cloud Console.
2. Create a new project by clicking on the project dropdown and selecting New Project.
3. Enable billing for your project.

Step 2: Enable Required APIs

You need to enable the Cloud Functions and Cloud Build APIs:

1. Navigate to APIs & Services > Library.
2. Search for Cloud Functions API and enable it.
3. Search for Cloud Build API and enable it.

Step 3: Setting Up Terraform Configuration

Create a new directory for your Terraform project and navigate into it:

mkdir terraform-serverless-functions
cd terraform-serverless-functions

Next, create a file named main.tf and add the following configuration:

provider "google" {
  project = "YOUR_PROJECT_ID"
  region  = "us-central1"
}

resource "google_storage_bucket" "function_bucket" {
  name     = "your-function-bucket"
  location = "US"
}

resource "google_cloudfunctions_function" "hello_world" {
  name        = "helloWorld"
  runtime     = "nodejs14"
  entry_point = "helloWorld"
  source_archive_bucket = google_storage_bucket.function_bucket.name
  source_archive_object = "function.zip"
  trigger_http = true
  available_memory_mb = 256

  # Define the environment variables for your function
  environment_variables = {
    ENV_VAR = "value"
  }
}

Step 4: Writing Your Function Code

Create a function.js file in the same directory, containing the following code:

exports.helloWorld = (req, res) => {
  res.send('Hello, World!');
};

Step 5: Package Your Function

You need to package your function into a zip file:

zip function.zip function.js

Step 6: Deploying with Terraform

1. Initialize your Terraform project:

bash terraform init

1. Review the execution plan:

bash terraform plan

1. Deploy your serverless function:

bash terraform apply

Confirm the action when prompted.

Step 7: Accessing Your Function

Once deployed, Terraform will output the URL for your function. You can access it using a web browser or tools like curl:

curl https://REGION-PROJECT_ID.cloudfunctions.net/helloWorld

Step 8: Modifying and Managing Your Function

To update your function, modify the code in function.js, re-zip the package, and run:

zip function.zip function.js

Then, update your Terraform configuration and apply the changes:

terraform apply

Troubleshooting Common Issues

• Function Not Triggering: Ensure that the trigger type is set correctly in the configuration.
• Permissions Issues: Make sure your Google Cloud account has the necessary permissions for deploying functions.
• Version Conflicts: Check compatibility between the runtime (e.g., Node.js version) and your code.

Conclusion

Deploying serverless functions with Terraform on Google Cloud simplifies the deployment process while providing a robust infrastructure management solution. With the ability to automate deployments and track changes, developers can focus on building applications rather than managing infrastructure. Start experimenting with serverless functions in your projects today and take advantage of the scalability and efficiency they offer!