Summary: It sometimes happens that there are already some existing `XMLHttpRequest` objects before we turn on the network inspector. So it is a must to check whether a `XMLHttpRequest` object has a property `_index` to determine if it should be tracked.
Reviewed By: davidaurelio
Differential Revision: D3635184
fbshipit-source-id: a5552d7244c994b0fe782ac35baae39ec7488494
Summary:
This diff
- creates `XHRInterceptor` to intercept all XMLHttpRequest network operations in React Native by monkey-patching.
- enables `XHRInterceptor` in RN development tool "inspector".
This interception and inspector tool work well on both Android and iOS. And this supports interception on any network API based on XMLHttpRequest, especially the Fetch API.
By now, we can intercept 12 information fields of a XMLHttpRequest including method, url, data sent, status, response type, response size, requestHeaders, responseHeaders, response, responseURL, responseType and timeout.
Follow-up:
- Will add UIs in the inspector on top of this diff, to display all the network operation information. (Not in this diff just to make this shorter)
- Will extend this to gather other valuable information towards one XMLHttpRequest.
- Should support other network request APIs like WebSocket.
Reviewed By: davidaurelio
Differential Revision: D3598873
fbshipit-source-id: 3221050ab2ebd876a718fc326646c344d0944a5f