How to make cypress wait for a response that depends on another response?

Question

From response A (/list.json) my app receives a list of items. Based on the output of A, my app makes another set of requests B for individual items (/one.txt, /two.txt, ...).

Now in my test I want to make sure that all responses B return HTTP 200.

Waiting (cy.wait) for response A is fine. However, waiting for responses B is more difficult, because I have to start waiting just upon receiving response A where I learn about responses B.

I tried 2 options:

1. start waiting inside of cy.wait of response A - code,
2. start waiting outside of cy.wait of response A - code

Neither of those work. With option 1 I get

`cy.wait()` timed out waiting `5000ms` for the 1st request to the route: `one.txt`. No request ever occurred

And with option 2 I get a pass, even though /two.txt doesn't exist. Looks like cy.wait for responses B is added after the responses were received

Answer 1

Since all requests are triggered off the visit, and are dynamic, you need a single intercept that handles all requests.

To me that means adding some javascript and dynamic aliases.

// avoid status code 304, disable browser cache
Cypress.automation('remote:debugger:protocol', {
  command: 'Network.clearBrowserCache'
})


describe('spec', () => {
  it('test', () => {
    let items = [];
    cy.intercept('GET', '*', (req) => {

      const slug = req.url.substring(req.url.lastIndexOf('/') + 1)
      if (slug === 'list.json') {
        req.alias = 'list'
      } 
      if (items.includes(slug)) {
        req.alias = 'item'
      }

      req.continue((res) => {
        if (slug === 'list.json')) {
          items = res.body;
        }  
      })
    })

    cy.visit('https://demo-cypress.netlify.app');  

    cy.wait('@list')                          // wait for list
      .then(() => {                           // now items is populated
        for (let item of items) {             // really just need the count
          cy.wait('@item').then(interception => {     // wait n-times
            expect(interception.response.statusCode).to.eq(200);
          })
        }
      })
  })
})