[0.54 - iOS] fetch HEAD requests fail with `Invalid response for blob`

[awinograd]

Performing a HEAD request with fetch causes an Invalid response for blob error on iOS

Environment

Environment:
OS: macOS Sierra 10.12.6
Node: 8.6.0
Yarn: Not Found
npm: 5.3.0
Watchman: 4.9.0
Xcode: Xcode 9.1 Build version 9B55
Android Studio: 3.0 AI-171.4443003

Packages: (wanted => installed)
react: 16.3.0-alpha.1 => 16.3.0-alpha.1
react-native: 0.54.0 => 0.54.0

Expected Behavior

The request should complete without error.

Actual Behavior

The RCTNetworking native module in iOS does not construct an empty blob for HEAD responses like Android does. Instead it returns an empty string as the response. However, whatwg-fetch always sets the responseType to blob for the XMLHttpRequest so the empty string is invalid.

Relevant lines of code:
https://github.com/github/fetch/blob/fcc4e1b48cfb5a2b1625fcd6eac06d954b00ccb6/fetch.js#L454
https://github.com/facebook/react-native/blob/6eef7de46ee5c5004854c1cdd5cd83f2a608f622/Libraries/Network/XMLHttpRequest.js#L253-L258

Invalid response for blob: 
handleException @ index.bundle?platform=ios&dev=true&minify=false:13132
handleError @ index.bundle?platform=ios&dev=true&minify=false:12174
reportFatalError @ index.bundle?platform=ios&dev=true&minify=false:783
__guardSafe @ index.bundle?platform=ios&dev=true&minify=false:2360
callFunctionReturnFlushedQueue @ index.bundle?platform=ios&dev=true&minify=false:2165
t @ RNDebuggerWorker.js:1

Steps to Reproduce

1 Clone and run https://github.com/lingokids/FetchError

(I tested on an iPhone 7)

[Lxxyx]

Same issue

[lukewis]

Seeing this error also with an HTTP GET that returns a 204 - NoContent. Works ok in 0.53 though.

[chienduc91]

Same issue

[regulus33]

Same Issue

[filipef101]

there is a fix

[filipef101]

https://github.com/reyalpsirc/react-native/commit/6b1831e6cd5b6a98c56a12e8566cb5c2a9b90df2

[filipef101]

It shouldn't be the best solution, but we really need our app to work offline

[zen0wu]

+1. It seems to fail some GET requests as well.

[genglei01]

Same Issue

[cuiyueshuai]

Same Issue，how to resolve the solution,
if the request's response is NoContent or void, app will report this error

[varqasim]

Hope this is going to be fixed soon, getting same error. Anyone has a workaround for this?

[satya164]

Does it happen on both Android and iOS or only iOS?