Awesome
Description
Jest Integration Test for serverless-aws-lambda
Requirements
Installation
yarn add -D serverless-aws-lambda-jest
# or
npm install -D serverless-aws-lambda-jest
Recommendations
Some recommendations to speed up jest integration tests by avoiding double bundeling of your Lambdas by Jest and serverless-aws-lambda.
- Use separate jest config files for you Unit and Integration test, example:
jest.it.config.js
(Integration Test)jest.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
jest.it.config.js
'srootDir
. - Set jestPlugin 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 { jestPlugin } = require("serverless-aws-lambda-jest");
module.exports = defineConfig({
plugins: [
jestPlugin({
configFile: "./jest.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:${process.env.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 of your test files which could be used to make offline request against the local server. - Set
oneshot
option totrue
to launch Integrations Tests and exit the process after the first test sequence. Node Process will exit with0
code, or1
if Jest tests fails or coverage threshold is not met.- It is also possible to delay exit process by passing
{delay: secondes}
tooneshot
.
- It is also possible to delay exit process by passing
- use
coverage
option to generate coverage result json file and svg badge. - See an example project