Pulumi Node.js Function

The NodejsFunction is a very simple component that streamlines the creation of a Node.js Lambda function in Pulumi by setting default values for architecture and runtime. It also creates an IAM role and assigns basic permissions for interacting with CloudWatch – arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole.

The instance includes helper methods like addPolicy() for creating new policies or using an existing policy's arn and attaching it to the aforementioned role.

There's also grantInvoke() method for assigning a resource-based policy to allow other services e.g., api gateway, to invoke the lambda.

Usage

import { NodejsFunction, NodejsFunctionArgs, Runtime } from '@exanubes/pulumi-nodejs-function'

const props: NodejsFunctionArgs = {
    code: new FileArchive("./functions"),
    handler: "hello_world.handler",
    runtime?: Runtime.NodeJS20,
    policy?: {
      name: "my-awesome-policy",
      policy: {
        Version: "2012-10-17",
        Statement: [
            {
                Action: ["dynamodb:PutItem"],
                Effect: "Allow",
                Resource: "*",
            },
        ],
    },
  }
}

const lambda = new NodejsFunction('lambda', props, pulumi_resource_options);

lambda.grantInvoke('resource-based-policy', 'apigateway.amazonaws.com', 'arn');
lambda.addPolicy("some-policy", {
    name: "my-awesome-policy",
    policy: {
        Version: "2012-10-17",
        Statement: [
            {
                Action: ["dynamodb:PutItem"],
                Effect: "Allow",
                Resource: "*",
            },
        ],
    },
});

Typescript support

The TypescriptAssetArchive class can be used for transpiling lambda handlers written in typescript into javascript. It's a simple wrapper around Pulumi's AssetArchive resource. It uses esbuild for transpiling the code to javascript and saving it in memory, creates a Pulumi StringAsset which is used to create an AssetArchive. The resulting file will have the same name with the extension changed from .ts to .js. Esbuild configuration can be modified by passing a second argument

const esbuildOptions: TypescriptAssetArchiveArgs = {}

const ts_lambda = new NodejsFunction("hello_world", {
  code: new TypescriptAssetArchive("./functions/hello_typescript.ts", esbuildOptions),
  handler: "hello_typescript.handler",
});