Unexpected token < error in ostrio:files

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1 
vm.tempImage = new FilesCollection({
            collection: tempImageCollection,
            onBeforeUpload: function (file) {
                if (file.size > (vm.config.maxUploadSize * 1024 * 1024)) {
                    return 'Please upload image, with size equal or less than ' + vm.config.maxUploadSize + 'MB';
                } else if (!(/png|jpg|jpeg/i.test(file.ext))) {
                    return 'File with "' + file.ext + '" extension not supported, Please upload "png | jpg" file';
                }
                return true;
            }
        });
vm.tempImage.insert({
                file: $input.files[0],
                streams: 'dynamic',
                chunkSize: 'dynamic',
                onProgress: function (progress) {
                    $timeout(function () {
                        console.log('Uploaded: ' + progress + '%');
                    }, 0);
                },
                onError: function (error) {
                    console.log(error);
                    notificationService.showError(error.reason);
                    if (callback) {
                        callback();
                    }
                }
            }, true);

$input.files[0] = {
  "meta": {},
  "ext": "jpg",
  "extension": "jpg",
  "extensionWithDot": ".jpg",
  "mime": "image/jpeg",
  "mime-type": "image/jpeg"
}

I am getting error unexpected token < in onError event of insert, after selection of image,
its working fine on development, issue is only on server.
I am using ostrio:files package for file upload.
Sever os : ubuntu