Google API for Google Docs, requesting a list of documents — 400 Bad Request

问题

After authentication from google servers for google docs, I do a simple getResponse, but I get a 400 Bad Request. I can't understand where am I going wrong. The sample code is, below

  private void executeRefreshAlbums() {
        HttpRequest request = transport.buildGetRequest();
        request.url = GoogleDocsUrl.forDefaultPrivateFull();
        System.out.println("URL = "+request.url);
        try {
            HttpResponse response = request.execute();
            System.out.println("Response = "+response.getContent());

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

  }

The sysout prints the correct url as

03-12 17:36:59.573: INFO/System.out(451): URL = https://docs.google.com/feeds/default/private/full

But When I do this, I get

03-12 17:43:41.360: WARN/System.err(3958): com.google.api.client.http.HttpResponseException: 400 Bad Request
03-12 17:43:41.415: WARN/System.err(3958):     at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:209)
03-12 17:43:41.415: WARN/System.err(3958):     at com.example.Test.executeRefreshAlbums(Test.java:198)
03-12 17:43:41.415: WARN/System.err(3958):     at com.example.Test.authenticated(Test.java:190)
03-12 17:43:41.415: WARN/System.err(3958):     at com.example.Test.authenticatedClientLogin(Test.java:156)
03-12 17:43:41.415: WARN/System.err(3958):     at com.example.Test.access$1(Test.java:153)
03-12 17:43:41.415: WARN/System.err(3958):     at com.example.Test$2$1.run(Test.java:139)
03-12 17:43:41.415: WARN/System.err(3958):     at android.os.Handler.handleCallback(Handler.java:587)
03-12 17:43:41.415: WARN/System.err(3958):     at android.os.Handler.dispatchMessage(Handler.java:92)
03-12 17:43:41.415: WARN/System.err(3958):     at android.os.Looper.loop(Looper.java:123)
03-12 17:43:41.415: WARN/System.err(3958):     at android.app.ActivityThread.main(ActivityThread.java:4363)
03-12 17:43:41.415: WARN/System.err(3958):     at java.lang.reflect.Method.invokeNative(Native Method)
03-12 17:43:41.415: WARN/System.err(3958):     at java.lang.reflect.Method.invoke(Method.java:521)
03-12 17:43:41.422: WARN/System.err(3958):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
03-12 17:43:41.422: WARN/System.err(3958):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
03-12 17:43:41.422: WARN/System.err(3958):     at dalvik.system.NativeStart.main(Native Method)

Any help would be really appreciated. I have been trying it for an hour now :-(

回答1:

At the other thread user @Merlin provided the solution which solved similar issue. His solution was to specify the API version number 3.0 in the request as stated in the "Google Documents List Data API" document:

Important: If you make a request to the API that uses a feature only available in version 3, but forget to set the version, you will most likely receive a 400 Bad Request response. Since the URL structure is different between versions 2 and 3, this is a common mistake made by new users of the API.

To specify a version number, use the GData-Version HTTP header. The value of this header must be 3.0. The decimal and the zero are required.

 GData-Version: 3.0

Alternatively, you can specify v=3 as a query parameter in the URL. This is often needed when working behind a firewall that strips HTTP headers, or from some JavaScript requests. Use of the HTTP header is recommended when possible.

  https://docs.google.com/feeds/default/private/full?v=3

回答2:

Not sure what the transport object your using is;

Here is a simple HttpGet request:

        HttpGet getMethod = new HttpGet(URI);  
        HttpParams params   = new BasicHttpParams();                        
        HttpConnectionParams.setConnectionTimeout(params, 30000);
        HttpConnectionParams.setSoTimeout(params, 30000);

        DefaultHttpClient httpClient = new DefaultHttpClient(params);
        HttpResponse response        = httpClient.execute(getMethod);

        BufferedReader in = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
        String returnString = "";
        String line = "";
        do
        {
         returnString += line;
         line = in.readLine();
        } while (line != null); 

Perhaps using this method instead you will get a more obvious error?

来源：https://stackoverflow.com/questions/5286400/google-api-for-google-docs-requesting-a-list-of-documents-400-bad-request