我按照google drive sdk中提到的所有步骤操作。我在我的设备上创建了一个示例应用程序（android，运行果冻豆），并且能够将文件上传到驱动器。当我尝试下载相同的文件时，我能够获取文件ID，fileTitle，fileDownloadURL等元数据，但无法下载内容。我收到401 Unauthorized错误。
我的应用AUTH SCOPE是AUTH_TOKEN_TYPE =“oauth2：https://www.googleapis.com/auth/drive.file”;
我正在执行以下操作来获取OAUTH令牌：
AccountManager am = AccountManager.get(this);
Bundle options = new Bundle();
am.getAuthToken(
mAccount,
AUTH_TOKEN_TYPE,
options,
this,
new OnTokenAcquired(),
new Handler(){
@Override
public void handleMessage(Message msg) {
invadiateToken();
super.handleMessage(msg);
}
});
基于令牌，这是我构建Drive对象的方式
Drive buildService(final String AuthToken) {
HttpTransport httpTransport = new NetHttpTransport();
JacksonFactory jsonFactory = new JacksonFactory();
Drive.Builder b = new Drive.Builder(httpTransport, jsonFactory, null);
b.setJsonHttpRequestInitializer(new JsonHttpRequestInitializer() {
@Override
public void initialize(JsonHttpRequest request) throws IOException {
DriveRequest driveRequest = (DriveRequest) request;
driveRequest.setPrettyPrint(true);
driveRequest.setKey(API_KEY);
driveRequest.setOauthToken(AuthToken);
}
});
return b.build();
}
我可以使用以下代码上传文件：
private void uploadLocalFileToDrive(Drive service) throws IOException{
// File's metadata.
String mimeType = "text/plain";
File body = new File();
body.setTitle("myText.txt");
body.setDescription("sample app by varun");
body.setMimeType("text/plain");
// File's content.
java.io.File fileContent = new java.io.File(mInternalFilePath);
FileContent mediaContent = new FileContent(mimeType, fileContent);
service.files().insert(body, mediaContent).execute();
}
在尝试下载此应用上传的同一个文件时，我从以下代码段中HttpResponse resp = service.getRequestFactory().buildGetRequest(url).execute()获得了401未经授权的错误
private void downloadFileFromDrive(Drive service) throws IOException {
Files.List request;
request = service.files().list();
do {
FileList files = request.execute();
for(File file:files.getItems()){
String fieldId = file.getId();
String title = file.getTitle();
Log.e("MS", "MSV:: Title-->"+title+" FieldID-->"+fieldId+" DownloadURL-->"+file.getDownloadUrl());
if (file.getDownloadUrl() != null && file.getDownloadUrl().length() > 0 ) {
GenericUrl url = new GenericUrl(file.getDownloadUrl());
HttpResponse resp = service.getRequestFactory().buildGetRequest(url).execute();
InputStream isd = resp.getContent();
Log.e("MS", "MSV:: FileOutPutStream--->"+getFilesDir().getAbsolutePath()+"/downloaded.txt");
} else {
Log.e("MS", "MSV:: downloadURL for this file is null");
}
}
request.setPageToken(files.getNextPageToken());
} while (request.getPageToken()!=null && request.getPageToken().length()>0);
}
任何人都可以帮助我，让我知道我做错了什么???
答案 0 :(得分：5)
这是一个已知问题，将通过发布Google Play Services API来解决。
由于您的应用程序已获得https://www.googleapis.com/auth/drive.file范围的授权，并且下载端点不支持?key=查询参数，因此我们的服务器无法知道哪个项目正在发出请求（确保该应用有权阅读此文件的内容。
与此同时，我建议的唯一解决方法是使用广泛的范围：https://www.googleapis.com/auth/drive。请在开发应用程序时使用，并等待Google Play服务发布。
要详细了解如何在Android中使用新的授权API，您可能会对这两个Google I / O会谈感兴趣：Building Android Applications that Use Web APIs和 Writing Efficient Drive Apps for Android
答案 1 :(得分：2)
我已回答了这个问题，以及所有相关的Android问题驱动器问题，在这里：
Android Open and Save files to/from Google Drive SDK
在那个答案中，我发布了一个用于从Google云端硬盘下载文件的方法的代码（如果以下代码本身不清楚，请查看我链接到的完整答案。）
private java.io.File downloadGFileToJFolder(Drive drive, String token, File gFile, java.io.File jFolder) throws IOException {
if (gFile.getDownloadUrl() != null && gFile.getDownloadUrl().length() > 0 ) {
if (jFolder == null) {
jFolder = Environment.getExternalStorageDirectory();
jFolder.mkdirs();
}
try {
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(gFile.getDownloadUrl());
get.setHeader("Authorization", "Bearer " + token);
HttpResponse response = client.execute(get);
InputStream inputStream = response.getEntity().getContent();
jFolder.mkdirs();
java.io.File jFile = new java.io.File(jFolder.getAbsolutePath() + "/" + getGFileName(gFile)); // getGFileName() is my own method... it just grabs originalFilename if it exists or title if it doesn't.
FileOutputStream fileStream = new FileOutputStream(jFile);
byte buffer[] = new byte[1024];
int length;
while ((length=inputStream.read(buffer))>0) {
fileStream.write(buffer, 0, length);
}
fileStream.close();
inputStream.close();
return jFile;
} catch (IOException e) {
// Handle IOExceptions here...
return null;
}
} else {
// Handle the case where the file on Google Drive has no length here.
return null;
}
}
答案 2 :(得分：0)
我认为我们不需要任何访问令牌来下载文件。我遇到了同样的问题，这很有效：
private class DownloadFile extends AsyncTask<Void, Long, Boolean> {
private com.google.api.services.drive.model.File driveFile;
private java.io.File file;
public DownloadFile(File driveFile) {
this.driveFile = driveFile;
}
@Override
protected Boolean doInBackground(Void... params) {
if (driveFile.getDownloadUrl() != null
&& driveFile.getDownloadUrl().length() > 0) {
try {
HttpResponse resp = mDriveService
.getRequestFactory()
.buildGetRequest(
new GenericUrl(driveFile.getDownloadUrl()))
.execute();
OutputStream os = new FileOutputStream(file);
CopyStream(resp.getContent(), os);
os.close();
return true;
} catch (IOException e) {
e.printStackTrace();
return false;
}
} else {
return false;
}
}
@Override
protected void onPostExecute(Boolean result) {
//use the file
}
}
public static void CopyStream(InputStream is, OutputStream os) {
final int buffer_size = 1024;
try {
byte[] bytes = new byte[buffer_size];
for (;;) {
int count = is.read(bytes, 0, buffer_size);
if (count == -1)
break;
os.write(bytes, 0, count);
}
} catch (Exception ex) {
}
}