Fetch API does not support getReader (response.body is undefined)

[lafkpages]

Description

When trying to read the response from Fetch as a stream, via getReader(), I get an error saying that resp.body is undefined. Logging the value of resp shows this:

{"_bodyBlob": {"_data": {"__collector": [Object], "blobId": "xxx", "name": "chat.txt", "offset": 0, "size": 42, "type": "text/plain"}}, "_bodyInit": {"_data": {"__collector": [Object], "blobId": "xxx", "name": "chat.txt", "offset": 0, "size": 42, "type": "text/plain"}}, "bodyUsed": false, "headers": {"map": {"cache-control": "no-store", "content-length": "42", "content-type": "text/plain; charset=utf-8", "date": "Sun, 21 May 2023 18:53:09 GMT", "expect-ct": "max-age=2592000, report-uri=\"https://sentry.repl.it/api/10/security/?sentry_key=xxx\"", "replit-cluster": "hacker", "strict-transport-security": "max-age=6123043; includeSubDomains", "uwebsockets": "20"}}, "ok": true, "status": 200, "statusText": "", "type": "default", "url": "https://xxx.luisafk.repl.co/chat"}

Duplicate of #25701 and #25910, but they were closed.

React Native Version

0.71.7

Output of npx react-native info

System:
    OS: macOS 12.6.3
    CPU: (8) x64 Intel(R) Core(TM) i7-6920HQ CPU @ 2.90GHz
    Memory: 346.30 MB / 16.00 GB
    Shell: 5.8.1 - /bin/zsh
  Binaries:
    Node: 19.7.0 - ~/.nvm/versions/node/v19.7.0/bin/node
    Yarn: 1.22.15 - ~/.nvm/versions/node/v19.7.0/bin/yarn
    npm: 9.5.0 - ~/.nvm/versions/node/v19.7.0/bin/npm
    Watchman: Not Found
  Managers:
    CocoaPods: Not Found
  SDKs:
    iOS SDK: Not Found
    Android SDK: Not Found
  IDEs:
    Android Studio: Not Found
    Xcode: /undefined - /usr/bin/xcodebuild
  Languages:
    Java: Not Found
  npmPackages:
    @react-native-community/cli: Not Found
    react: 18.2.0 => 18.2.0 
    react-native: 0.71.7 => 0.71.7 
    react-native-macos: Not Found
  npmGlobalPackages:
    *react-native*: Not Found

Steps to reproduce

Try the code example below.

Snack, code example, screenshot, or link to a repository

const resp = await fetch('https://example.com');
const reader = resp.body.getReader();

[github-actions[bot]]

:warning:

Newer Version of React Native is Available!

:information_source:

You are on a supported minor version, but it looks like there's a newer patch available - 0.71.8. Please upgrade to the highest patch for your minor or latest and verify if the issue persists (alternatively, create a new project and repro the issue in it). If it does not repro, please let us know so we can close out this issue. This helps us ensure we are looking at issues that still exist in the most recent releases.

[lafkpages]

I upgraded and it still does not work.

[Liquidibrium]

Same issue: respnse.json() is valid, however response.body is undefined

[rbndg]

This issue has been lingering in RN for so long and many people have complained about it. As it stands now fetch within RN is not spec complaint https://github.com/facebook/react-native/issues/27741

[codergautam]

Any update? Do I have to use third party fetch?

[lafkpages]

Since what I wanted to do was streaming, I ended up using WebSockets, but this should really just be fixed.

[github-actions[bot]]

This issue is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[rbndg]

Typical react native negligence

On Sun, 25 Feb 2024 at 4:01 pm, github-actions[bot] < @.***> wrote:

This issue is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.

— Reply to this email directly, view it on GitHub https://github.com/facebook/react-native/issues/37505#issuecomment-1962813611, or unsubscribe https://github.com/notifications/unsubscribe-auth/ABHCJEIXFXJP2TICTVKMJGLYVLAR7AVCNFSM6AAAAAAYJSHQZWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTSNRSHAYTGNRRGE . You are receiving this because you commented.Message ID: @.***>

[etler]

With all the AI APIs using SSE this is becoming more and more important. I can use websockets for internal streaming, but where we need to support SSE style APIs that's not an option. Most commercial APIs will prefer to offer streaming over HTTP.

[LunatiqueCoder]

I managed to find a solution here: #27741