Devtools should talk to the development server instead of localhost

[ckknight]

Is this a bug report?

Yes

Have you read the Bugs section of the How to Contribute guide?

Yes

Environment

1. react-native -V: 0.46.3
2. node -v: v6.11.0
3. npm -v: 3.10.10
4. yarn --version: not used

Then, specify:

• Target Platform: iOS

• Development Operating System: macOS

• Build tools: using XCode to successfully deploy to an iPhone 7

Steps to Reproduce

(Write your steps here:)

1. Deploy a debug build of a react-native app to a real device on WiFi
2. Use a remote debugging tool such as Nuclide or react-native-debugger

Expected Behavior

React DevTools should work just as it does when running in the simulator.

Actual Behavior

In the debugger on my computer, the message "Waiting for React to connect..." appears and never goes away.

Instead of communicating to my computer, React DevTools is attempting to communicate via localhost which is the phone.

The offending line is https://github.com/facebook/react-native/blob/master/Libraries/Core/Devtools/setupDevtools.js#L33

A working replacement for 'localhost' is require('NativeModules').SourceCode.scriptURL.split('://')[1].split('/')[0].split(':')[0], which works on-device and in-simulator, but there is likely a much better solution.

Reproducible Demo

All react-native projects are affected.

[ckknight]

The sibling file of getDevServer.js seems ideal to solve this - it's not obvious why it wasn't used.

[nahuelhds]

This would be nice when working with Expo as well!

[pull-bot]

Hi there! This issue is being closed because it has been inactive for a while. Maybe the issue has been fixed in a recent release, or perhaps it is not affecting a lot of people. Either way, we're automatically closing issues after a period of inactivity. Please do not take it personally!

If you think this issue should definitely remain open, please let us know. The following information is helpful when it comes to determining if the issue should be re-opened:

• Does the issue still reproduce on the latest release candidate? Post a comment with the version you tested.
• If so, is there any information missing from the bug report? Post a comment with all the information required by the issue template.
• Is there a pull request that addresses this issue? Post a comment with the PR number so we can follow up.

If you would like to work on a patch to fix the issue, contributions are very welcome! Read through the contribution guide, and feel free to hop into #react-native if you need help planning your contribution.