Nock VS msw

So, why would you want a REAL server to mock request/reponses? You have a lot of intercepts today that sit on the network layer and you can define things like "If you send request to that endpoint, with that json, please return that Status" (for NodeJS example, Nock - https://github.com/nock/nock)

That said, folks seem to like "recording" features in these sorts of tools (Ruby's VCR, nock, etc), so maybe there's a future where I add something similar. I've always just found the ergonomics of those features awkward to deal with, especially having to flip back and forth between tests and fixtures files to figure out what's wired to what, but maybe there's a clean solution... perhaps a "live request" mode that just prints mock code snippets of request/response pairs passing through your app.

While not mocking per say I usually use nock for http calls. You can use nock.recorder.rec() to capture the http call to play back during test, That way you are always using "live" code but not making real calls to servers.

I looked at the service which is used to get the feed URLs from a blog URL and noticed it takes the html response of the blog URL and gets the links ( tags) by checking the type attribute value against a list of valid feed values. So, I decided to use a similar approach by getting the html response for a provided URL and checking the Content-Type header against a list of valid MIME types for a feed. I ended up updating the logic to test if a URL is a feed URL, returning it if true. If the URL is found to not be a feed URL, it would try to get the feed URLs assuming the URL is a blog URL. I tested and confirmed that the new logic worked for both blog and feed URLs. Then, I added some tests for the new function I added to test for a feed URL. Testing this ended up being simpler than I expected as all I had to do was mock the response of a test url (using nock), and then check if the function returned the correct boolean value for a url. I created a PR and noticed that some of the tests in another file were now failing. While I was investigating this, I got a review on my PR, requesting me to add another test to the file which had the failing tests. That file tested the API service as a whole. I found out that nock only mocks a URL's response for one request by default. And since I was now checking for a feed URL as well, the function which returned the feed URLs from a blog URL was throwing an error since the nock for that was used up. To fix this, I had to specify in the nock statement to mock the URL response for two requests:

There are libraries like https://github.com/nock/nock to prevent mocking the whole axios.

Use nock: https://github.com/nock/nock

Going based off the documentation I sent you in my last reply, there is an example that uses nock to emulate api responses. I haven't used nock myself, but the example seems pretty simple to use. You just need to take the example and change the response object to be the shape of what your getStuffFromDatabase function returns. That way your useCategory function runs as close to normally as possible, while providing a mock response value instead of hitting the database.

If you’re willing to venture into nodejs territory, then nock is a fantastic and simple to set up http mock server. https://github.com/nock/nock

However, I discovered a great combination that transformed my API call testing in TypeScript: Vitest and Mock Service Worker (MSW). Their well-crafted design makes them incredibly easy to use, enhancing the overall testing experience.

While mocks are effective, they require modifying the component's internal logic or mocking global functions like fetch. This can become cumbersome for complex components with numerous API interactions. Here's where MSW shines.

> For those wondering what the use case is, you must not have tried it. It does take work to set up (with each version that's less), but it can be very nice to test in isolation esp in cases where a component is under a login, the 4th page of a 10 page form, etc. Also obviously if you're working on a component library that ships without an app, Storybook can be your development and/or demo app.

I have worked with storybook extensively over the past couple of years and my team is moving away from it in favour of MSW (https://mswjs.io).

For "4th page of a 10 page form" during the development there's hot reloading which is really stable nowadays and haven't failed me, although I understand that some setups are old and it might be easier to configure Storybook than good hot reloading.

I'm not entirely sure about the testing part of it and I'd be grateful if you could elaborate. I haven't felt the need for some special setup with SB because for unit tests, I can test a deeply nested component separately. For E2E tests, I usually test the whole form.

I agree on the component library part, this is probably the only use case where Storybook is 100% justified, but I'm unconvinced about the

Additionally, thank you to all our community launch partners across the frontend ecosystem for helping us bring Storybook 8 to the world! Thanks to Chromatic, Figma, ViteConf, Omlet, DivRiots, story.to.design, StackBlitz, UXpin, Nx, Mock Service Worker, Anima, Zeplin, zeroheight, kickstartDS, and Kendo UI.

similar with msw.js, but fully automated

they could be network mocks (use msw)

With orval, we can also integrate the API client in our unit tests. Orval provides first class support for mocking through the (Mock Service Worker)[https://mswjs.io/] library, and it can automatically generate the MSW handlers for testing server.

Consider a hypothetical scenario where data from a list of companies within an ERP needs to be retrieved. As a personal recommendation, leverage tools like MSW for top-level mocks, which can significantly enhance the testing process.