Using aws lambda with fsx

Question

Pulumi · Accepted Answer

When integrating AWS Lambda with Amazon FSx, you're essentially creating a setup where Lambda functions can access a file system hosted on FSx. AWS Lambda is a compute service that lets you run code without provisioning or managing servers, and Amazon FSx provides fully managed third-party file systems with the native compatibility and feature sets for workloads such as home directories, Windows-based storage, high-performance computing, machine learning, and electronic design automation.

To integrate AWS Lambda with FSx, we need to:

1. Create an Amazon FSx file system.
2. Create an IAM role and policy that grants the Lambda function permissions to access the file system.
3. Set up a Lambda function with access to the file system.

This setup will allow your Lambda function to mount the FSx file system and interact with it, just like it would with any file system.

Below is a Pulumi program in TypeScript that performs these tasks.

```typescript
import * as aws from "@pulumi/aws";

// Create an Amazon FSx file system (using FSx for Windows as an example)
const windowsFileSystem = new aws.fsx.WindowsFileSystem("windowsFileSystem", {
    storageCapacity: 300,
    subnetIds: ["subnet-xxxxxx"], // Replace with your actual subnet ID
    securityGroupIds: ["sg-xxxxxx"], // Replace with your actual Security Group ID
    // Ensure you have the right storage type, throughput capacity, and other setup.
});

// Create a Lambda execution role with FSx access
const lambdaFsxRole = new aws.iam.Role("lambdaFsxRole", {
    assumeRolePolicy: aws.iam.assumeRolePolicyForPrincipal({ Service: "lambda.amazonaws.com" }),
});

const fsxAccessPolicy = new aws.iam.Policy("fsxAccessPolicy", {
    description: "A policy that allows a lambda function to access FSx",
    policy: windowsFileSystem.arn.apply(arn => JSON.stringify({
        Version: "2012-10-17",
        Statement: [{
            Effect: "Allow",
            Action: [
                "fsx:*",
            ],
            Resource: arn,
        }],
    })),
});

new aws.iam.RolePolicyAttachment("lambdaFsxPolicyAttachment", {
    role: lambdaFsxRole.name,
    policyArn: fsxAccessPolicy.arn,
});

// Create an AWS Lambda function that connects to the FSx file system
const lambdaFunction = new aws.lambda.Function("myFsxLambdaFunction", {
    runtime: aws.lambda.NodeJS12dXRuntime,
    handler: "index.handler", // Replace with your actual handler
    code: new pulumi.asset.AssetArchive({
        ".": new pulumi.asset.FileArchive("./path/to/your/lambda/code"), // Replace with your actual Lambda function code directory
    }),
    role: lambdaFsxRole.arn,
    fileSystemConfig: {
        arn: windowsFileSystem.arn,
        localMountPath: "/mnt/fsx", // The path where the FSx will be mounted in the Lambda environment
    },
    // Additional settings as needed, such as timeout, memory size, etc.
});

// Export the Lambda and FSx ARNs
export const lambdaArn = lambdaFunction.arn;
export const fsxArn = windowsFileSystem.arn;
```

Explanation:

- We create an AWS FSx file system resource (`aws.fsx.WindowsFileSystem`) specifying the storage capacity, the subnet, and the security group. The subnet should allow the AWS Lambda function and FSx to communicate.
- Then we create an IAM Role (`aws.iam.Role`) for the Lambda function with an assume role policy that enables Lambda functions to assume the role.
- We define an IAM Policy (`aws.iam.Policy`) that allows the Lambda function to perform actions on FSx and associate this policy with our Lambda role using `aws.iam.RolePolicyAttachment`.
- We define an AWS Lambda function (`aws.lambda.Function`) with a file system configuration that includes the ARN of the FSx file system and a local mount path inside the Lambda environment.
- Finally, we export the ARN of the Lambda function and the FSx file system for reference.

To proceed with this setup:

1. Replace placeholder values like subnet IDs, security group IDs, and the path to your Lambda function code with your specific values.
2. Ensure you have the AWS CLI and Pulumi CLI installed and configured with appropriate access rights.
3. Save the above code in a `index.ts` file and initialize a Pulumi project with `pulumi new aws-typescript`.
4. Run `pulumi up` to provision and deploy this setup.

Ensure that your AWS credentials are correctly configured to allow creation of these resources. If you don't have the right permissions, the Pulumi program will fail to create the resources and display an error message.