response.body isn't converted to JSON if content-type is application/vnd.api+json

[jazwiecki]

Current behavior:

If a response comes back with a content-type header set to application/vnd.api+json, response.body does not contain JSON:

Object
body: Blob {size: 4370, type: "application/vnd.api+json"}
headers: {content-length: "1877", content-type: "application/vnd.api+json"}
__proto__: Object

I think this is because request.coffee only returns JSON if content-type exactly matches application/json, based on these lines in the develop branch:

contentTypeIsJson: (response) ->
      ## TODO: use https://github.com/jshttp/type-is for this
      response?.headers?["content-type"]?.includes("application/json")

Those lines include a TODO which suggests using type-is to improve on the potential JSON content-type pattern-matching.

Desired behavior:

Cypress XHR responses with a content-type of application/vnd.api+json also have their bodies parsed as JSON. Happy to write a PR to use type-is to handle application\/[\S]+?\+?json$ if no one objects.

Steps to reproduce: (app code and test code)

This spec will write a fixture file without the bodies of the responses, they will all be undefined:

describe('Cypress does not parse JSON API', () => {
  // We declare an empty array to gather XHR responses
  const xhrData = [];
  after(() => {
    // In record mode, save gathered XHR data to local JSON file
    if (Cypress.env('RECORD')) {
      const path = './cypress/fixtures/fixture.json';
      cy.writeFile(path, xhrData);
    }
  });
  it('Works', () => {
    cy.server({
      // Here we handle all requests passing through Cypress' server
      onResponse: (response) => {
        if (Cypress.env('RECORD')) {
          const url = response.url;
          const method = response.method;
          const data = response.body;
          // We push a new entry into the xhrData array
          xhrData.push({ url, method, data });
        }
      },
    });
    // This tells Cypress to hook into any GET request
    if (Cypress.env('RECORD')) {
      cy.route({
        method: 'GET',
        url: '*',
      });
    }
    if (!Cypress.env('RECORD')) {
      cy.fixture('fixture').then((data) => {
        for (let i = 0, length = data.length; i < length; i++) {
          cy.route(data[i].method, data[i].url, data[i].data);
        }
      });
    }


    cy.visit('/');
  });
});

Versions

$ npx cypress --version
Cypress package version: 3.1.5
Cypress binary version: 3.1.5

[cypress-bot]

The code for this is done in cypress-io/cypress#5166, but has yet to be released.
We'll update this issue and reference the changelog when it's released.

[cypress-bot]

Released in 3.5.0.