Rename WebView postMessage method to postMessageNative.

[soldovskii]

Rename WebView postMessage to postMessageNative. The old name "postMessage" breaks the functional of some scripts in WebView using cross-domain communication via postMessage. Example: https://api-maps.yandex.ru/2.1/?lang=ru_RU

Motivation (required)

The old name "postMessage" breaks the functional of some scripts in WebView using cross-domain communication via postMessage. This bug avalible if WebView has onMessage callback.

Test Plan (required)

Not working

Working

Send message to react-native WebView - window.postMessageNative("data", "*");

Replace original window.postMessage - bad idea;

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[farazs]

I think something like window.rnBridge.postMessage would be preferable. It would also let you use the built-inJavascriptInterface directly on Android. The current implementation is slightly bugged.

[axten]

This PR is strongly needed, because many users get Error Setting onMessage on a WebView overrides existing values of window.postMessage, but a previous value was defined.
see #10865 for detailed info.
postMessage is official browser api, see MDN for info.

[Thomas101]

Just ran into this today. Real pain :(

[mcmar]

The current implementation is completely 100% broken and unusable. Using it results in a red page that says Setting onMessage on a WebView overrides existing values of window.postMessage, but a previous value was defined. It always results in that red page, no matter what you do.

Given that context, I think we should merge this. Something is clearly better than nothing. And even nothing is better than something that's 100% broken.

[davidgross]

100% agree with @mcmar we are needing to be able to use onMessage for an app we are building.

[twairball]

Current implementation breaks for webviews that load Meteor js content, which uses window.postMessage

[shergin]

I believe we can fix this without breaking backward compatibility. What if we can call window.originalPostMessage inside our overridden postMessage?

[twairball]

window.postMessage is a browser API. The subject issues are due to RCTWebview hijacking this window function.

In the case for RN Webviews I think its safe to assume we are using postMessage to achieve some kind of bridging between webview <--> RN ?

If so, if the concern is breaking backwards compatibility, does it make sense to instead have a parallel window.postMessageNative that doesn't impact current window.postMessage?

[neerfri]

@mkonicek is this an acceptable PR to solve #10941 ?
(as you suggest in #10941 (comment))

[nazrdogan]

@twairball Did you solve your problem. I m facing same issue.

[facebook-github-bot]

@soldovskij I tried to find reviewers for this pull request and wanted to ping them to take another look. However, based on the blame information for the files in this pull request I couldn't find any reviewers. This sometimes happens when the files in the pull request are new or don't exist on master anymore. Is this pull request still relevant? If yes could you please rebase? In case you know who has context on this code feel free to mention them in a comment (one person is fine). Thanks for reading and hope you will continue contributing to the project.

[twairball]

@nazrdogan the proposed changes in this PR work. I made my own fork for current version react-native (warning; lots of work) and added similar changes for renaming postMessage to postMessageNative

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Maybe the issue has been fixed in a recent release, or perhaps it is not affecting a lot of people. If you think this issue should definitely remain open, please let us know why. Thank you for your contributions.

[henrylearn2rock]

This should definitely not be closed.

[patientplatypus]

Yeah, so this issue (see here: #10865) was brought up in 2016 and I'm still getting it in production. And a bot automatically closes a PR to fix this? Get it together you guys.

[ohtangza]

This PR is something we MUST have. Currently, it conflicts several web SDKs including Google's, which relies on window.postMessage.