How Do I Store Backend State in S3 Using Automation API?

Introduction

In this guide, we will explore how to store backend state in AWS S3 using Pulumi’s Automation API. Storing the backend state in S3 is crucial for managing the state files of your infrastructure as code projects. The Automation API allows you to programmatically manage Pulumi programs, providing flexibility and automation capabilities. We will walk through the process of creating an S3 bucket and configuring it as the backend for state storage using a Pulumi program.

Step-by-Step Guide

Step 1: Configure the Pulumi Automation API

Begin by configuring the Pulumi Automation API to use an S3 bucket as the backend. This involves setting up the necessary configurations to direct the backend state to the S3 bucket.

Step 2: Write and Execute the Pulumi Program

Next, you will write a Pulumi program that provisions the required infrastructure and ensures the S3 bucket is used for storing the state files. Once written, execute the program using the Automation API.

Code

Below is the TypeScript code that demonstrates how to set up the backend state in an S3 bucket using Pulumi’s Automation API:

import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";
import * as automation from "@pulumi/pulumi/automation";

// Automation API program
async function run() {
    // Create a new Pulumi program
    const stack = await automation.LocalWorkspace.createOrSelectStack({
        stackName: "dev",
        projectName: "s3-backend",
        program: async () => {},
    });

    // Set the backend to the S3 bucket
    await stack.workspace.installPlugin("aws", "v6.70.0");
    await stack.setConfig("aws:region", { value: "us-west-2" });
    await stack.workspace.setConfig("backend-url", `s3://${bucket.bucket}`);

    // Run the update
    await stack.up();
}

run().catch(err => console.error(err));

Explanation of the Code

Automation API Program

• Create or Select Stack: The automation.LocalWorkspace.createOrSelectStack function creates or selects a Pulumi stack, which acts as a container for your infrastructure’s state.

• Program Definition: The program argument is where you define the Pulumi program. In this example, it is intended to create an S3 bucket to be used as the backend, although the specific creation logic is not detailed in the snippet.

• Configuration: The setConfig method sets the AWS region and specifies the S3 bucket as the backend URL for the Pulumi stack.

• Execute Program: The stack.up() function runs the Pulumi program to apply the infrastructure changes.

This code snippet configures the Pulumi Automation API to use an S3 bucket as the backend. You can extend the program function to include additional resources as needed.

Running the Code

• Ensure you have Pulumi and AWS credentials properly configured on your system.
• Execute the TypeScript file using ts-node or compile it to JavaScript and run it with node.

Key Points

• The Pulumi Automation API allows for programmatic management of infrastructure as code projects.
• Storing state in S3 provides a reliable and scalable solution for managing infrastructure state files.
• The setup involves creating or selecting a Pulumi stack and configuring it to use an S3 bucket as the backend.

Conclusion

By following this guide, you can effectively manage your Pulumi backend state using an S3 bucket. This approach not only secures your state files but also leverages AWS’s scalable storage capabilities. The Automation API further enhances your ability to automate and manage your infrastructure programmatically, enabling seamless integration into CI/CD pipelines and other automated workflows.