Using Pretender with `fetch`. #60

rwjblue · 2015-03-17T13:49:41Z

It would be nice to be able to use fetch instead of XMLHttpRequest. When using the non-native fetch polyfil Pretender would likely still work (because the polyfill uses XMLHttpRequest to implement fetch), but it doesn't seem that native fetch requests would be handled by Pretender.

Spec: https://fetch.spec.whatwg.org

This issue is mostly to lay out a path forward.

/cc @cowboyd @toranb

The text was updated successfully, but these errors were encountered:

trek · 2015-03-17T13:55:30Z

I'm down for it. I'd like to extend and generalize pretender to mock out several browser APIs that might seem unrelated but have to be controlled for isolated tests: xhr, fetech, geolocation, etc.

stefanpenner · 2015-03-17T13:57:42Z

The polyfil for fetch does use xhr https://github.com/github/fetch/blob/master/fetch.js#L263

So that buys us time until someday where native fetch can be used cross platform

stefanpenner · 2015-03-17T15:43:18Z

Also the ember wrapper never falls back to native fetch

topaxi · 2015-05-21T08:48:02Z

I tried to use pretender with fetch, but as FF and Chrome now ship fetch, this isn't working for now.

stefanpenner · 2015-05-21T14:34:10Z

If you use ember-fetch it will always use the polyfil (for better or worse)

topaxi · 2015-05-21T15:41:34Z

Oh, thx, I'll consider it :)

trek · 2015-05-21T18:26:30Z

I'd happily accept a PR, I just don't have a need for fetch myself right now so that work should be handled by a more vested party.

ddcahutton · 2016-07-22T01:33:38Z

This feels really dirty, but, to force whatwg-fetch to apply in Chrome, I did the following in the HTML I run my tests against:

<script>
window.fetch = undefined;
</script>
<script src="my-code-including-fetch-polyfill.js"></script>

dustinfarris · 2016-10-21T13:35:19Z

This looks interesting https://github.com/sstur/fetch-pretender

@rwjblue

tl;dr - This commit add support for fetch. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Pretender has been working well with xhr, but doesn't handle fetch. It's been 2 years since @rwjblue first open the [issue](pretenderjs#60) for fetch support. So people don't need to do extra work to polyfill for testing. Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender will "just work". Per Yetch homepage, the supplement set of yetch impl and spec include: - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. For `fake_xml_http_request` impl, the request is resolved once its state is changed to `DONE` so the `reject` is not cathed. So the senario happens in pretender is: 1. state chagne to `DONE`, trigger resolve request 2. abort, trigger reject 3. xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.

@rwjblue

tl;dr - This commit add support for fetch. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Motivation ------ Pretender has been working well with xhr, but doesn't handle fetch. It's been 2 years since @rwjblue first open the [issue](pretenderjs#60) for fetch support. So people don't need to do extra work to polyfill for testing. Changes ------ Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender should "just work". Caveats ------ 1. The supplement set of yetch impl and spec includes (not complete): - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) 2. Abort - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. As implemented in `fake_xml_http_request`, the request is resolved once its state is changed to `DONE`. So the senario happens in pretender is: 1). state chagne to `DONE`, trigger resolve request 2). abort, trigger reject 3). xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. 3. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.

@rwjblue

tl;dr - This commit adds support for fetch. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Motivation ------ Pretender has been working well with xhr, but doesn't handle fetch. It's been 2 years since @rwjblue first open the [issue](pretenderjs#60) for fetch support. So people don't need to do extra work to polyfill for testing. Changes ------ Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender should "just work". Caveats ------ 1. The supplement set of yetch impl and spec includes (not complete): - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) 2. Abort - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. As implemented in `fake_xml_http_request`, the request is resolved once its state is changed to `DONE`. So the senario happens in pretender is: 1). state changes to `DONE`, trigger resolve request 2). abort, trigger reject 3). xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. 3. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.

tl;dr - This commit adds support for fetch, fix pretenderjs#60. - pretender swap native fetch related API if exists - pretender.shutdown() restore native fetch related API - doesn't work with AbortController Changes ------ Include a fetch ponyfill and swap the native fetch during pretender creation, then restore them when `shutdown`. Since fetch polyfill uses xhr behind the scene, pretender should "just work". Caveats ------ 1. The supplement set of yetch impl and spec includes (not complete): - Inability to [set the redirect mode](JakeChampion/fetch#137) - Inability to [change the cache directive](JakeChampion/fetch#438 (comment)) - Inability to [disable same-origin cookies](JakeChampion/fetch#56 (comment)) 2. Abort - `xhr.abort()` first set state to done, finally response to a [network error](https://xhr.spec.whatwg.org/#the-abort()-method); - [fetch](https://dom.spec.whatwg.org/#aborting-ongoing-activities) will reject promise with a new "AbortError" DOMException. As implemented in `fake_xml_http_request`, the request is resolved once its state is changed to `DONE`. So the scenario happens in pretender is: 1). state changes to `DONE`, trigger resolve request 2). abort, trigger reject 3). xhr.onerror, trigger reject The first resolve wins, error thus not rejected but an empty request is resolved. 3. Though polyfilled by xhr, fetch returns a Promise and is asynchronous by nature.

trek mentioned this issue Dec 11, 2015

Pretender doesn't work with new fetch API. #131

Closed

kategengler mentioned this issue Feb 19, 2016

Should this wrapper use native fetch, when available? ember-cli/ember-fetch#13

Closed

mitchlloyd mentioned this issue Jul 31, 2016

Replace ember-ajax with ember-network. orbitjs/ember-orbit#118

Merged

morhook mentioned this issue Mar 31, 2017

support ember-network fetch mocking miragejs/ember-cli-mirage#983

Closed

rwjblue mentioned this issue Nov 5, 2017

refactor(jQuery): Remove $.ajax, use async/await, move custom paths t… miragejs/ember-cli-mirage#1206

Closed

xg-wang mentioned this issue May 15, 2018

use browser fetch if exists ember-cli/ember-fetch#63

Merged

xg-wang mentioned this issue May 23, 2018

fetch support #230

Merged

stefanpenner closed this as completed in #230 Jul 16, 2018

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Using Pretender with `fetch`. #60

Using Pretender with `fetch`. #60

rwjblue commented Mar 17, 2015

trek commented Mar 17, 2015

stefanpenner commented Mar 17, 2015

stefanpenner commented Mar 17, 2015

topaxi commented May 21, 2015

stefanpenner commented May 21, 2015

topaxi commented May 21, 2015

trek commented May 21, 2015

ddcahutton commented Jul 22, 2016

dustinfarris commented Oct 21, 2016

Using Pretender with fetch. #60

Using Pretender with fetch. #60

Comments

rwjblue commented Mar 17, 2015

trek commented Mar 17, 2015

stefanpenner commented Mar 17, 2015

stefanpenner commented Mar 17, 2015

topaxi commented May 21, 2015

stefanpenner commented May 21, 2015

topaxi commented May 21, 2015

trek commented May 21, 2015

ddcahutton commented Jul 22, 2016

dustinfarris commented Oct 21, 2016

Using Pretender with `fetch`. #60

Using Pretender with `fetch`. #60