Description

Vitest Integration Test for serverless-aws-lambda

Requirements

serverless-aws-lambda

Installation

yarn add -D serverless-aws-lambda-vitest
# or
npm install -D serverless-aws-lambda-vitest

Recommendations

Some recommendations to speed up Vitest integration tests by avoiding double bundeling of your Lambdas by Vitest and serverless-aws-lambda.

Use separate vitest config files for you Unit and Integration test, example:
- vitest.it.config.js (Integration Test)
- vitest.ut.config.js (Unit Test)
Do not write your Integration Tests inside the same (sub) directory as your Lambda handlers
Specify your Integrations Test root directory inside your vitest.it.config.js's include and/or exclude.
Set vitestPlugin at the end of your defineConfig plugins array.

Usage

use serverless-aws-lambda's defineConfig to import this plugin

// config.js
const { defineConfig } = require("serverless-aws-lambda/defineConfig");
const { vitestPlugin } = require("serverless-aws-lambda-vitest");

module.exports = defineConfig({
  plugins: [
    vitestPlugin({
      configFile: "./vitest.it.config.js",
      oneshot: false,
      coverage: {
        outDir: "./coverage/",
        json: true,
        badge: true,
        threshold: 60,
      },
    }),
  ],
});

Testing async events

The plugin exposes multiple global functions to wait for handler async invokation responses.

Simple example of implementation for a SQS event:

import { SQSClient, SendMessageCommand } from "@aws-sdk/client-sqs";

const client = new SQSClient({
  region: "eu-west-3",
  endpoint: `http://localhost:${LOCAL_PORT}/@sqs`,
});

const cmd = new SendMessageCommand({
  QueueUrl: "MyQueueName",
  MessageBody: JSON.stringify({
    hello: {
      message: "world",
      firstVisit: true,
    },
  }),
});

test("Single SQS", async () => {
  const res = await client.send(cmd);
  const handlerResponse = await sqsResponse(res.MessageId);
  expect(handlerResponse.success).toBe(true);
});

see more examples.

Coverage

Supported events

Application Load Balancer (alb)
API Gateway (http, httpApi)
DynamoDB Streams
S3
SNS
SQS

Notes

serverless-aws-lambda's LOCAL_PORT env variable is injected into process.env (also globally if option is enabled in vitest config) of your test files which could be used to make offline request against the local server.
Set oneshot option to true to launch Integrations Tests and exit the process after the first test sequence. Node Process will exit with 0 code, or 1 if Vitest tests fails or coverage threshold is not met.
- It is also possible to delay exit process by passing {delay: secondes} to oneshot.
use coverage option to generate coverage result json file and svg badge.

Inqnuam / serverless-aws-lambda-vitest