How to authenticate Google Drive without requiring the user to copy/paste auth code?

Question

I\'m playing around with the DriveCommandLine applicaiton to learn the Drive API a bit. I\'m just wondering if it is possible to authenticate my desktop application with Google

Answer 1

Step 1: Generate the URL using offline access type

flow = new GoogleAuthorizationCodeFlow.Builder(
httpTransport, jsonFactory, CLIENT_ID, CLIENT_SECRET, Arrays.asList(DriveScopes.DRIVE))
.setAccessType("offline")
.setApprovalPrompt("auto").build();
String url = flow.newAuthorizationUrl().setRedirectUri(REDIRECT_URI).build();

Step 2: Store the credentials accessToken and refreshToken

GoogleTokenResponse response = flow.newTokenRequest(code).setRedirectUri(REDIRECT_URI).execute();
            GoogleCredential credential = new GoogleCredential.Builder().setTransport(httpTransport)
                .setJsonFactory(jsonFactory)
                .setClientSecrets(CLIENT_ID, CLIENT_SECRET)
                .build()
                .setFromTokenResponse(response);
String accessToken = credential.getAccessToken();
String refreshToken = credential.getRefreshToken();

Step 3: Reuse tokens when needed

GoogleCredential credential1 = new GoogleCredential.Builder().setJsonFactory(jsonFactory)
.setTransport(httpTransport).setClientSecrets(CLIENT_ID, CLIENT_SECRET).build();
credential1.setAccessToken(accessToken);
credential1.setRefreshToken(refreshToken);
Drive service = new Drive.Builder(httpTransport, jsonFactory, credential1).build();

Step 4: Understand OAuth to handle errors and refreshing of the tokens