Cordova File Plugin Bug (Android)

To Recreeate

• Run cordova prepare android
• Run cordova build android
• Open in android studio
• See console output (via Chrome Remote Debug or Logcat)

The file is not read correctly, it is much longer than it should be.

The problem

CordovaResourceApi.java method OpenForReadResult return a -1 length to Filesystem.java method readFileAtURL causing file corruption as each chunk effectively has no end.

Fix

Possible fix in the plugin cordova-plugin-file:

https://github.com/apache/cordova-plugin-file/pull/217
https://issues.apache.org/jira/browse/CB-13245?jql=text%20~%20%22CordovaResourceApi%22

Or should it be fixed upstream in cordova-android here:

https://github.com/apache/cordova-android/blob/master/framework/src/org/apache/cordova/CordovaResourceApi.java

In the method OpenForReadResult there is one path (in the catch) that leaves the length as -1 causing the defect

case URI_TYPE_ASSET: {
                String assetPath = uri.getPath().substring(15);
                AssetFileDescriptor assetFd = null;
                InputStream inputStream;
                long length = -1;
                try {
                    assetFd = assetManager.openFd(assetPath);
                    inputStream = assetFd.createInputStream();
                    length = assetFd.getLength();
                } catch (FileNotFoundException e) {
                    // Will occur if the file is compressed.
                    inputStream = assetManager.open(assetPath);
                }
                String mimeType = getMimeTypeFromPath(assetPath);
                return new OpenForReadResult(uri, inputStream, mimeType, length, assetFd);
            }

Adding length = inputStream.available(); in the catch fixes the issue for me, but I’m not a java developer so can’t evaluate if that’s a bad idea for another reason.