serverless-offline VS supertest

Using local emulators like sam local, serverless-offline, localstack, etc.

Hi, I'm the creator of serverless-offline (https://github.com/dherault/serverless-offline), a NPM package for local serveless development on AWS.

I'm building a cool product and intend to launch Q1 2023. To gain traction from my target customers, I plan to place a discrete ad at the launch of every serverless-offline instance.

Does it seem like an ok move to you? Or is it something that repels you?

Best,

As the creator of serverless-offline, I am well placed to tell you that this is the time-effective solution. Plus, it costs way less than other solutions at smaller scales. But, again, going Kubernetes or otherwise will be a problem for the future.

https://github.com/dherault/serverless-offline https://github.com/lambci/docker-lambda

What if I didn’t need to push code to AWS every time I wanted to test something? All heroes don’t wear capes. Like a knight in shining armor, Serverless Offline comes barging in to save the day! At least now I can test all my code locally before pushing it to AWS. That’s a relief.

With classic Express servers, you can use a simple node script to get the server up and running to test locally. Serverless wants to be run in the AWS ecosystem making it. Lucky for us, David Hérault has built and continues to maintain serverless-offline allowing us to emulate our functions locally before we deploy.

With the serverless offline plugin you can speed up local dev is by emulating AWS lambda and API Gateway locally when developing your Serverless project.

Those mocks are by definition not real services so there are some behavior differences between the local environment and the cloud provider. For example, AWS API Gateway emulated by serverless-offline doesn't handle VTL locally the same as AWS does.

serverless-offline (https://github.com/dherault/serverless-offline) is a great tool to use for local development of serverless applications.

It's not a complete mirror image of what you get but it's close enough in my experience.

Supertest is quite popular and easy to use test tool, you can do integration and E2E test as well, you just need to pass it the server instance or a string to make a request and assert over the response.

If the latter, there are a bunch of different options for writing automated tests. One popular way is using Jest to run your tests. If you're trying to test the backend end-to-end flow, you could use Supertest to make requests and assert on the responses.

I did something similar with a full stack Typescript project, using supertest and node-fetch. It was nice.

Unit, Integration and E2E tests using Jest and Supertest

This is why integration tests > unit tests. I really hate mocking and I never bother testing individual units that don't affect how users use my app and code. In your case, I'd just use something like supertest to test this functionality e2e.

Yes, but when every function handler is separate from the router, then you can use node-mocks-http to test each handler, to test the router is simpler to use supertest to write integration tests, for E2E tests I personally recommend [pactum](pactumjs.github.io/)

Simple booking api attempt with Typescript, Express, TypeORM and Postgres. Testing with Jest & Supertest.

In a Node.js application, writing API tests is a good start. They provide more coverage than unit testing. You can use frameworks like Supertest, Jest, or any other library that provides a high-level abstraction for testing APIs.

supertest npm package that helps test HTTP

If you want to write integration tests - https://jestjs.io - https://github.com/visionmedia/supertest