Google Drive - Authorize once on a single machine - google-app-engine

Question

I am new to Google Drive and have following scenarios for which I am not able to find anything (not sure if anything exists or not)
–> I am creating a Windows app which will be SAAS based. Different Users will register and create their company logins and subusers under them. Now I want them to put the google drive credentials in one of the form and this should work for rest of the users. Currently the problem is that while development I got the google log in done and it never asks for the login again but when testing on a different system with different login, it keeps asking for google login. I simply want admin users to put their google drive credentials and it should work for upload and download files for all the users for that company.
–> I want to keep versions of the same file (just like google drive does by default) on google drive. Lets say user A uploaded file xyz and then user B downloaded and changed file xyz and uploaded it on the drive again.
I want 2 things here – only the changed content should get uploaded and not the whole file (this will save time for the user)
2ndly I want to have history of the same file so I can show in my Windows application
#region Get Service Object
UserCredential credential = GoogleWebAuthorizationBroker.AuthorizeAsync(
new ClientSecrets
{
ClientId = "GoogleDriveClientID",
ClientSecret = "GoogleDriveClientSecret"
},
new[] { DriveService.Scope.Drive }, "user", CancellationToken.None).Result;
// Create the service.
service = new DriveService(new BaseClientService.Initializer()
{
HttpClientInitializer = credential,
ApplicationName = "AppName",
});
#endregion
#region Uploading
public void uploadOnGoogleDrive(ObservableCollection<JobAttachments> AttachmentsColl, bool IsDocSaved)
{
try
{
service = getServiceObject();
List<Google.Apis.Drive.v2.Data.File> fileList = retrieveAllFiles(service);
List<Google.Apis.Drive.v2.Data.File> directoryList = GetDirectoryList(service);
if (IsDocSaved)
{
#region for checking if the file already exists
foreach (Google.Apis.Drive.v2.Data.File item in fileList)
{
foreach (JobAttachments attach in AttachmentsColl)
{
if (item.Title == attach.AttachmtGUID)
{
MessageBoxResult result = System.Windows.MessageBox.Show(LogMessages.GetResourceMessage(LogMessages.MessageEnumeration.GD_AlreadyExistsMsg), "Confirmation", MessageBoxButton.YesNoCancel);
if (result == MessageBoxResult.Yes)
{
//DeleteFile(service, item);
Google.Apis.Drive.v2.Data.File body = new Google.Apis.Drive.v2.Data.File();
body.Title = attach.AttachmtGUID;
body.MimeType = item.MimeType;
fileSize = body.FileSize;
byte[] byteArray = System.IO.File.ReadAllBytes(attach.AttachmentName);
System.IO.MemoryStream stream = new System.IO.MemoryStream(byteArray);
FilesResource.UpdateMediaUpload request = service.Files.Update(body, item.Id, stream, item.MimeType);
request.Upload();
}
else
{
return;
}
break;
}
}
}
#endregion
}
else
{
#region for direct uploading on google drive
if (AttachmentsCollection != null && AttachmentsCollection.Count > 0)
{
string folderID = string.Empty;
if (_IsProject)
{
if (directoryList != null && directoryList.Count > 0)
{
foreach (var dir in directoryList)
{
if (dir.Title.Equals(_ProjectName))
{
folderID = dir.Id;
break;
}
}
}
if (string.IsNullOrEmpty(folderID))
{
Google.Apis.Drive.v2.Data.File foldbody = new Google.Apis.Drive.v2.Data.File();
foldbody.Title = _ProjectName;
foldbody.MimeType = "application/vnd.google-apps.folder";
foldbody.Parents = new List<ParentReference>() { new ParentReference() { Id = "root" } };
Google.Apis.Drive.v2.Data.File file = service.Files.Insert(foldbody).Execute();
folderID = file.Id;
}
}
else
{
//project folder
string prjFolder = string.Empty;
string tskFolder = string.Empty;
Google.Apis.Drive.v2.Data.File foldbody;
if (directoryList != null && directoryList.Count > 0)
{
foreach (var dir in directoryList)
{
if (dir.Title.Equals(_ProjectName))
{
prjFolder = dir.Id;
break;
}
}
}
if (string.IsNullOrEmpty(prjFolder))
{
foldbody = new Google.Apis.Drive.v2.Data.File();
foldbody.Title = _ProjectName;
foldbody.MimeType = "application/vnd.google-apps.folder";
foldbody.Parents = new List<ParentReference>() { new ParentReference() { Id = "root" } };
Google.Apis.Drive.v2.Data.File file = service.Files.Insert(foldbody).Execute();
prjFolder = file.Id;
}
//task folder
if (directoryList != null && directoryList.Count > 0)
{
foreach (var dir in directoryList)
{
if (dir.Title.Equals(_TaskName) && dir.Parents[0].Id.Equals(prjFolder))
{
folderID = dir.Id;
break;
}
}
}
if (string.IsNullOrWhiteSpace(folderID))
{
foldbody = new Google.Apis.Drive.v2.Data.File();
foldbody.Title = _TaskName;
foldbody.MimeType = "application/vnd.google-apps.folder";
foldbody.Parents = new List<ParentReference>() { new ParentReference() { Id = prjFolder } };
Google.Apis.Drive.v2.Data.File file1 = service.Files.Insert(foldbody).Execute();
folderID = file1.Id;
}
}
foreach (JobAttachments item in AttachmentsColl)
{
if (!string.IsNullOrEmpty(item.AttachmentName))
{
Google.Apis.Drive.v2.Data.File body = new Google.Apis.Drive.v2.Data.File();
body.Title = item.AttachmtGUID;
body.MimeType = item.MimeType;
body.Parents = new List<ParentReference>() { new ParentReference() { Id = folderID } };
//fileSize = body.FileSize;
byte[] byteArray = System.IO.File.ReadAllBytes(item.AttachmentName);
System.IO.MemoryStream stream = new System.IO.MemoryStream(byteArray);
FilesResource.InsertMediaUpload request = service.Files.Insert(body, stream, item.MimeType);
request.Upload();
}
}
}
#endregion
}
}
catch (Exception ex)
{
if (ex.InnerException != null)
throw ex.InnerException;
}
}
#endregion
#region Download File
private async Task DownloadFile(DriveService service, string url, string title, long? fSize)
{
service = getServiceObject();
var downloader = new MediaDownloader(service);
//downloader.ChunkSize = 256 * 1024;
downloader.ProgressChanged += Download_ProgressChanged;
var fileName = string.Empty;
//for downloading on system
var SaveFileDialog = new SaveFileDialog();
SaveFileDialog.Title = "Save As";
SaveFileDialog.FileName = title;
Nullable<bool> result = SaveFileDialog.ShowDialog();
if (result == true)
fileName = SaveFileDialog.FileName;
else if (result == false)
{
prgrsBar.StyleSettings = new ProgressBarStyleSettings();
prgrsBar.Value = 0;
return;
}
else
{
if (Directory.Exists(#"\Downloads"))
fileName = #"\Downloads\" + title;
}
if (!string.IsNullOrWhiteSpace(fileName))
using (var fileStream = new System.IO.FileStream(fileName, System.IO.FileMode.Create, System.IO.FileAccess.Write))
{
fileSize = fSize;
var progress = await downloader.DownloadAsync(url, fileStream);
if (progress.Status.ToString() == DownloadStatus.Completed.ToString())
{
fName = fileStream.Name;
prgrsBar.StyleSettings = new ProgressBarStyleSettings();
prgrsBar.Value = 0;
fileStream.Flush();
}
if (progress.Status.ToString() == DownloadStatus.Failed.ToString())
{
HandleDocuments.IsEditButtonClicked = false;
MessageBox.Show("Failed......." + progress.Exception.Message);
}
}
}
#endregion
#region Delete File
private Task DeleteFile(DriveService service, Google.Apis.Drive.v2.Data.File file)
{
service = getServiceObject(); //comment this if calling from another function; create the service object in that function and pass it as parameter to this function.
service.Files.Delete(file.Id).ExecuteAsync();
service.Files.EmptyTrash();
return null;
}
#endregion
#region Get all Directories and Files from Google Drive
public List<Google.Apis.Drive.v2.Data.File> GetDirectoryList(DriveService service)
{
//Creating the global list
List<Google.Apis.Drive.v2.Data.File> AllDirectories = new List<Google.Apis.Drive.v2.Data.File>();
//setting up the Request.
FilesResource.ListRequest request = service.Files.List();
//MaxResults: How many we want back at a time max is 1000
request.MaxResults = 1000;
//Q: Search results. all i want are folders that havent been trashed (deleted)
request.Q = "mimeType='application/vnd.google-apps.folder' and trashed=false";
do
{
try
{
// getting the results
FileList files = request.Execute();
// adding the results to the list.
AllDirectories.AddRange(files.Items);
// If there are more results then your MaxResults you will have a nextPageToken to get the rest of the results.
request.PageToken = files.NextPageToken;
}
catch (Exception ex)
{
request.PageToken = null;
if (ex.InnerException != null)
throw ex.InnerException;
}
} while (!String.IsNullOrEmpty(request.PageToken));
List<Google.Apis.Drive.v2.Data.File> DirsInRoot = AllDirectories.Where(a => (a.Parents.Count > 0 && a.Parents.FirstOrDefault().IsRoot.HasValue) ? a.Parents.FirstOrDefault().IsRoot.Value : false).ToList<Google.Apis.Drive.v2.Data.File>();
List<string> HirearcyList = new List<string>();
// The first Dir is Root it doesnt get returned. But we need it if we
// Want to be able to list the files that are in the root dir.
HirearcyList.Add("Root");
// recersive magic here.
foreach (Google.Apis.Drive.v2.Data.File myDir in DirsInRoot)
{
HirearcyList.Add(" " + myDir.Title);
HirearcyList.AddRange(RecsiveDir(AllDirectories, myDir.Id, " "));
}
return AllDirectories;
}
public List<String> RecsiveDir(List<Google.Apis.Drive.v2.Data.File> allDirs, string ParentId, string Prefix)
{
List<string> result = new List<string>();
List<Google.Apis.Drive.v2.Data.File> DirsInParentId = allDirs.Where(a => (a.Parents.Count > 0 && a.Parents.FirstOrDefault().IsRoot.HasValue) ? a.Parents.FirstOrDefault().Id == ParentId : false).ToList<Google.Apis.Drive.v2.Data.File>();
foreach (Google.Apis.Drive.v2.Data.File myDir in DirsInParentId)
{
result.Add(Prefix + myDir.Title);
result.AddRange(RecsiveDir(allDirs, myDir.Id, Prefix + " "));
}
return result;
}
public static List<Google.Apis.Drive.v2.Data.File> retrieveAllFiles(DriveService service)
{
List<Google.Apis.Drive.v2.Data.File> result = new List<Google.Apis.Drive.v2.Data.File>();
FilesResource.ListRequest request = service.Files.List();
request.MaxResults = 1000;
do
{
try
{
FileList files = request.Execute();
result.AddRange(files.Items);
request.PageToken = files.NextPageToken;
//service.Revisions.List(files.Items[0].Id) // for getting the file Revision history
}
catch (Exception ex)
{
request.PageToken = null;
if (ex.InnerException != null)
throw ex.InnerException;
}
} while (!String.IsNullOrEmpty(request.PageToken));
return result;
}
#endregion
Thanks
Jatinder