Can't query over HTTP on React Native

[cobarx]

I've been trying to pull tags off mp3 and m4a files stored on a web server. This works great when I do it in node, but when I try from React Native I've been hitting a couple issues.

First, overrideMimeType is not implemented on the version of XMLHTTPRequest that ships with React Native. I attempted to force it to load xhr2 but didn't have much luck. I was able to get past that point by commenting out that call and replacing it with: xhr._mimeOverride = "text/plain; charset=x-user-defined";

The next issue I ran into is that it's not properly retrieving the data. I get a warning: Received data was not a string, or was not a recognised encoding. It looks like this causes ChunkedFileData getByteAt to fail with: Offset 0 hasn't been loaded yet.

I'll look into this further tomorrow but was hoping you might have some insights on where to start.

[aadsm]

@davidroeca, is this something you have experienced?

[davidroeca]

@aadsm I honestly haven't tried, I've only worked with local files using the ReactNativeFileReader. The issue at hand is with https://github.com/aadsm/jsmediatags/blob/master/src/XhrFileReader.js

Maybe alternative logic for the following?

https://github.com/aadsm/jsmediatags/blob/7d5902a2a8e6e06a350506bf689cc7cff3d4dece/src/XhrFileReader.js#L300-L312

[cobarx]

@davidroeca Let me give that a shot and see if I can get it to load xhr2. Fixing that might handle the rest of the issues. Will keep you guys posted.

[cobarx]

I did a bit of reading and React Native's implementation of fetch & XMLHTTPRequest don't support binary blobs, so I don't think xhr2 will work either. They just landed binary blob support in 0.54 so once that is final, I'm going to take another look at this. I'm a bit too short on time to spend much time debugging at the moment.

[tomsotte]

Hi @cobarx do you by any chance gotten around the problem Offset 0 hasn't been loaded yet.?

[heaversm]

Just as a note for anyone still trying to solve this on RN. I had to essentially just replicate the overrideMimeType function in XhrFileReader.js in order to preven the error from being thrown, which I copied from the xhr2 library:

xhr.overrideMimeType = function(newMimeType) {
  if (this.readyState === XMLHttpRequest.LOADING || this.readyState === XMLHttpRequest.DONE) {
    throw new InvalidStateError("overrideMimeType() not allowed in LOADING or DONE");
  }
  this._mimeOverride = newMimeType.toLowerCase();
  return void 0;
}

xhr.overrideMimeType("text/plain; charset=x-user-defined");