Cypress - How to verify if a file is downloaded?

Question

I would like to check that a file is downloaded as part of my test. I only need to confirm that the file is downloaded after clicking a button. I have no need to read the file and its contents. All the files I am downloading are zips, not sure if that makes them harder to read?

it('Initiate download', () => {
  cy.get('[id="download-button"]')
    .should('be.visible')
    .click()
 });

 it('Verify the downloaded file', () => {
   cy.readFile('/Downloads/fileName.zip')
     .should('exist')
 });

https://stackoverflow.com/questions/47930881/how-can-i-use-cypress-io-to-assert-that-a-file-download-has-been-initiated-witho — Tom1425, Mar 04 '21 at 22:41
Checking that a file exists in the downloads folder does not verify that the file has just been downloaded as it may be there from a previous test — josef, Mar 29 '23 at 16:46
...unless Cypress downloads it to its own downloads folder and overwrites any previous files. I had to use a plugin to leverage this feature — josef, Mar 31 '23 at 11:37

score 31 · Answer 1 · answered Apr 30 '21 at 06:39

31

You can try this

const path = require("path");

it('Verify the downloaded file', () => {
   const downloadsFolder = Cypress.config("downloadsFolder");
   cy.readFile(path.join(downloadsFolder, "fileName.zip")).should("exist");
});

answered Apr 30 '21 at 06:39

Husnul Aman

489
3
11

Be aware of [this issue](https://github.com/cypress-io/cypress/issues/14857) though... – Marc-André Lafortune Dec 22 '21 at 23:28
1

Some other approaches like [this](https://stackoverflow.com/a/62787541/1175496) and [this](https://docs.cypress.io/api/commands/task#Read-a-file-that-might-not-exist) use `cy.task(...)`, because they use node modules like `fs.existsSync(...)`. This answer is elegant because it uses `cy.readFile(...)`; it doesn't need `cy.task(...)` so it's short and easy. However, for me, the downloaded file is a large PDF, and so `readFile` (or logging the file contents to cy log as part of the assertion) *slowed down my test*, maybe I should use `{log: false}`. Or use "exists" approach instead of "read" – Nate Anderson Jan 21 '22 at 05:24

score 8 · Answer 2 · answered Nov 10 '22 at 18:28

8

According to the Cypress documentation (https://docs.cypress.io/api/commands/readfile#Existence), it is enough to just call

cy.readFile(myFile.txt) // GOOD

Do not call

cy.readFile(myFile.txt).should('exist') // BAD

I was experiencing some performance problem with Cypress 10, when I called .should('exist'). This was very slow and ended in some timeouts.

answered Nov 10 '22 at 18:28

René Winkler

6,508
7
42
69

In addition I used the path "cypress/downloads/myFile.txt" to make it work – stereo Jul 10 '23 at 09:40

score 1 · Answer 3 · answered May 12 '22 at 10:32

1

I also ran into the same issue but got resolved by using a double backslash for the download folder path and this resolved my issue

it('Verify the downloaded file', () => {
   cy.readFile('cypress\\Downloads\\fileName.zip')
   .should('exist')
 });

answered May 12 '22 at 10:32

shreyas

37
1
11

score 0 · Answer 4 · answered Jun 28 '23 at 17:22

All that syntactic sugar can be avoided by using cy-verify-download:

cy.verifyDownload('picture.png');

// verify download by file extension or partial filename
cy.verifyDownload('.png', { contains: true });
cy.verifyDownload('pic', { contains: true });

// or increase timeout
cy.verifyDownload('archive.zip', { timeout: 25000 });

// or increase timeout and interval pooling
cy.verifyDownload('archive.zip', { timeout: 25000, interval: 600 });

score -1 · Answer 5 · answered Aug 18 '23 at 13:24

-1

You can checkout and use this template that cypress provides for your case: https://github.com/cypress-io/cypress-example-recipes/tree/master/examples/testing-dom__download

answered Aug 18 '23 at 13:24

timoblume

76
3

Cypress - How to verify if a file is downloaded?

5 Answers5