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fixture

Load a fixed set of data located in a file.

Syntax

cy.fixture(filePath)
cy.fixture(filePath, encoding)
cy.fixture(filePath, options)
cy.fixture(filePath, encoding, options)

Usage

Correct Usage

cy.fixture('users').as('usersJson')  // load data from users.json
cy.fixture('logo.png').then((logo) => {
  // load data from logo.png
})

Arguments

filePath (String)

A path to a file within the fixturesFolder , which defaults to cypress/fixtures.

You can nest fixtures within folders and reference them by defining the path from the fixturesFolder:

cy.fixture('users/admin.json') // Get data from {fixturesFolder}/users/admin.json

encoding (String)

The encoding to be used when reading the file. The following encodings are supported:

  • ascii
  • base64
  • binary
  • hex
  • latin1
  • utf8
  • utf-8
  • ucs2
  • ucs-2
  • utf16le
  • utf-16le

options (Object)

Pass in an options object to change the default behavior of cy.fixture().

Option Default Description
timeout responseTimeout Time to wait for cy.fixture() to resolve before timing out

Yields

cy.fixture() yields the contents of the file. Formatting is determined by its file extension.

Examples

JSON

Load a users.json fixture

cy.fixture('users.json').as('usersData')

Omit the fixture file’s extension

When no extension is passed to cy.fixture(), Cypress will search for files with the specified name within the fixturesFolder (which defaults to cypress/fixtures) and resolve the first one.

cy.fixture('admin').as('adminJSON')

The example above would resolve in the following order:

  1. cypress/fixtures/admin.json
  2. cypress/fixtures/admin.js
  3. cypress/fixtures/admin.coffee
  4. cypress/fixtures/admin.html
  5. cypress/fixtures/admin.txt
  6. cypress/fixtures/admin.csv
  7. cypress/fixtures/admin.png
  8. cypress/fixtures/admin.jpg
  9. cypress/fixtures/admin.jpeg
  10. cypress/fixtures/admin.gif
  11. cypress/fixtures/admin.tif
  12. cypress/fixtures/admin.tiff
  13. cypress/fixtures/admin.zip

Images

Image fixtures are sent as base64

cy.fixture('images/logo.png').then((logo) => {
  // logo will be encoded as base64
  // and should look something like this:
  // aIJKnwxydrB10NVWqhlmmC+ZiWs7otHotSAAAOw==...
})

Change encoding of Image fixture

cy.fixture('images/logo.png', 'binary').then((logo) => {
  // logo will be encoded as binary
  // and should look something like this:
  // 000000000000000000000000000000000000000000...
})

Playing MP3 file

cy.fixture('audio/sound.mp3', 'base64').then((mp3) => {
  const uri = 'data:audio/mp3;base64,' + mp3
  const audio = new Audio(uri)

  audio.play()
})

Accessing Fixture Data

Using .then() to access fixture data

cy.fixture('users').then((json) => {
  cy.route('GET', '/users/**', json)
})

Using fixtures to bootstrap data

Check out our example recipe using cy.fixture() to bootstrap data for our application.

Using an alias to access a fixture

You can make use of aliasing, .as(), instead of working directly with the yielded data.

Using an alias provides the benefit of terseness and readability. It also makes it easier to access the data later in your tests.

cy.fixture('users').as('usersJSON')
cy.route('GET', '/users/**', '@usersJSON')

// ...later on...

cy.get('#email').then(() => {
  // we have access to this.usersJSON since it was aliased
  this.usersJSON
})

Modifying fixture data before using it

You can modify fixture data directly before passing it along to a route.

cy.fixture('user').then((user)  => {
  user.firstName = 'Jane'
  cy.route('GET', '/users/1', user).as('getUser')
})

cy.visit('/users')
cy.wait('@getUser').then((xhr)  => {
  expect(xhr.requestBody.firstName).to.eq('Jane')
})

Notes

Shortcuts

Using fixture or fx shortcuts

Fixtures can also be referenced directly without using the .fixture() command by using the special keywords: fixture: or fx: within cy.route().

cy.route('GET', '/users/**', 'fixture:users') // this works
cy.route('GET', '/users/**', 'fx:users')      // this also works

Validation

Automated File Validation

Cypress automatically validates your fixtures. If your .json, .js, or .coffee files contain syntax errors, they will be shown in the Command Log.

Encoding

Default Encoding

Cypress automatically determines the encoding for the following file types:

  • .json
  • .js
  • .coffee
  • .html
  • .txt
  • .csv
  • .png
  • .jpg
  • .jpeg
  • .gif
  • .tif
  • .tiff
  • .zip

For other types of files, they will be read as utf8 by default, unless specified in the second argument of cy.fixture().

this context

If you store and access the fixture data using this test context object, make sure to use function () { ... } callbacks. Otherwise the test engine will NOT have this pointing at the test context.

describe('User page', () => {
  beforeEach(function () {
    // "this" points at the test context object
    cy.fixture('user')
      .then(() => {
        // "this" is still the test context object
        this.user = user
      })
  })

  // the test callback is in "function () { ... }" form
  it('has user', function () {
    // this.user exists
    expect(this.user.firstName).to.equal('Jane')
  })
})

Rules

Requirements

  • cy.fixture() requires being chained off of cy.

Assertions

  • cy.fixture() will only run assertions you've chained once, and will not retry.

Timeouts

  • cy.fixture() should never time out.

Because cy.fixture() is asynchronous it is technically possible for there to be a timeout while talking to the internal Cypress automation APIs. But for practical purposes it should never happen.

Command Log

  • cy.fixture() does not log in the Command Log

See also

© 2017 Cypress.io
Licensed under the MIT License.
https://docs.cypress.io/api/commands/fixture.html