Cordova File Plugin, none of the callbacks are firing

Question

Using http://plugins.cordova.io/#/package/org.apache.cordova.file and plugin installed = org.apache.cordova.file 1.3.3 "File"

I capture a picture and am trying to convert it to base64. The picture location returned (var path below) is "assets-library://asset/asset.JPG?id=ECB406E6-E361-46AA-9282-FEEBDAC170DF&ext=JPG"

At first from the documentation it looked like all I needed is:

   // Convert to image URL base64
   var fileReader = new FileReader();
   fileReader.onloadend = function (data) {
        console.log(data.target.result);
   };

   fileReader.readAsDataURL(path);

The code executed but the callback never fired! I then dug around and added a bunch of other fileReader options... exactly zero of which actually execute. Same behavior on both iOS and Android

        fileReader.onload = function (data) {
            console.log("onload", data);
        };


        fileReader.onerror = function (data) {
            console.log("error!", data);
        };


        fileReader.onloadstart = function (data) {
            console.log("onloadstart", data);
        };

I'm not getting any JS errors, but I'm also not getting any console output.

1) Why are the Cordova File FileReader() callbacks not firing?

Update

I tried using ngCordova's file plugin as well, http://ngcordova.com/docs/plugins/file/

$cordovaFile.readAsDataURL('assets-library://asset/', 'asset.JPG?id=ECB406E6-E361-46AA-9282-FEEBDAC170DF&ext=JPG')
            .then(function (success) {
                // success
                console.log("ng success", success);
            }, function (error) {
                // error
                console.log("ng error", error);
            });

With that I receive the following error:

Error in Success callbackId: File1336724899 : TypeError: undefined is not a function (evaluating 'e.getFile')

Answer 1

I had recently the same problem with moveFile function, in my case I was making a mistake. In the function moveFile, I was sending the directory with the file name, in the moveFrom parameter in my service. The correct way is set only the directory.

function moveFile(moveFrom, currentFileName, moveTo, newFileName) {
    return $cordovaFile.moveFile(moveFrom, currentFileName, cordova.file.dataDirectory + moveTo, newFileName);
}

Cordova file plugin could return an invalid directory error.

See the complete issue in ng-cordova repository

https://github.com/driftyco/ng-cordova/issues/1160

Answer 2

I've gone through numerous SO posts and forums regarding this behavior. The Error in Success callbackId: issues occurs on my iOS version of the application we are building, but not Android. Upon further investigation (with logging behavior in ngCordova source code itself) I found that assets-library://asset/ translates to a NATIVE_URI in Cordova, which is a FileEntry object in the W3 File System API spec that is designed from: FileEntry Interface

Using a FILE_URI (which in my case, I was using the cordova camera plugin and was easily configurable), I noticed that I was now using a DirectoryEntry object, and provided the getFile function I was looking for: DirectoryEntry Interface

TL;DR: Try using FILE_URI (file://) instead of NATIVE_URI ('assets-library://asset/' for iOS) to get DirectoryEntry objects that provide a getFile function.