Can I log via the API before a UI test in order to skip the login form?

[GrayedFox]

I've got my own, separate Cypress project set up that runs tests against the Cypress Real World App (great way to practise different Cypress commands and tests, thanks team!).

At the moment I am simply trying to save some time by avoiding logging in via the login form when doing UI / integration tests. The custom auth command logs the user in (200) and the connect.sid cookie is set (it is also present on the next request), but when I try to visit http://localhost:3000/transaction/new immediately afterwards I am still redirected to the login page (despite having a valid auth cookie).

Not sure what I'm missing? I'm posting this as a discussion because I assume this is down to me not fully understanding the auth mechanism(s) of the express/react Real World App. What else does the custom auth command need to do to make the Real World App recognise that a user is logged in?

// commands.js

// Authenticate via the API using a POST request 
Cypress.Commands.add('auth', (uri, username, password) => {
  cy.fixture('auth.json').then((authData) => {
    
    uri = uri || `${Cypress.env("apiUrl")}/login`
    username = username || authData.post.username
    password = password || authData.post.password
  
    return cy.request('POST', uri, {
        username: username,
        password: password,
        type: authData.post.type
    })
  })
})

// transaction.spec.js

describe('Transactions', () => {
  beforeEach(() => {
    cy.auth()
  })
  
  context('GET /users (contacts) on transaction page', () => {
    it('displays contacts after clearing the search bar', () => {
      cy.visit('http://localhost:3000/transaction/new')
        .get('#user-list-search-input')
        .click()
        .type('test')
        .clear()
        .get('ul[data-test="users-list"]')
        .should('not.be.empty')
    })
  })
})