I am using this tutorial in order to connect a xamarin.forms app with easy tables. I cannot add data to the database in Azure as i get
System.InvalidOperationException
The error message is the following
An insert operation on the item is already in the queue.
The exception happends in the following line of code.
await usersTable.InsertAsync(data);
In order to add a user
var user = new User { Username = "username", Password = "password" };
bool x = await AddUser(user);
AddUser
public async Task<bool> AddUser(User user)
{
try
{
await usersTable.InsertAsync(user);
await SyncUsers();
return true;
}
catch (Exception x)
{
await new MessageDialog(x.Message.ToString()).ShowAsync();
return false;
}
}
SyncUsers()
public async Task SyncUsers()
{
await usersTable.PullAsync("users", usersTable.CreateQuery());
await client.SyncContext.PushAsync();
}
where
IMobileServiceSyncTable<User> usersTable;
MobileServiceClient client = new MobileServiceClient("url");
Initialize
var path = Path.Combine(MobileServiceClient.DefaultDatabasePath, "DBNAME.db");
var store = new MobileServiceSQLiteStore(path);
store.DefineTable<User>();
await client.SyncContext.InitializeAsync(store, new MobileServiceSyncHandler());
usersTable = client.GetSyncTable<User>();
Please check your table. You probably have added the item already. Also, I would suggest that you don't set the Id property for your entity, because you might be inserting a same ID that's already existing in your table. It's probably the reason why the exception is appearing.
Hope it helps!
Some debugging you can do:
1) Turn on diagnostic logging in the backend and debug the backend: https://adrianhall.github.io/develop-mobile-apps-with-csharp-and-azure/chapter8/developing/#debugging-your-cloud-mobile-backend
2) Add a logging delegating handler in your MobileServiceClient setup: https://adrianhall.github.io/develop-mobile-apps-with-csharp-and-azure/chapter3/server/#turning-on-diagnostic-logs
The MobileServicePushFailedException contains an inner exception that contains the actual error. Normally, it is one of the 409/412 HTTP errors, which indicates a conflict. However, it can also be a 404 (which means there is a mismatch between what your client is asking for and the table name in Easy Tables) or 500 (which means the server crashed, in which case the server-side diagnostic logs indicate why).
Easy Tables is just a Node.js service underneath the covers.
Related
I don't use transactions in my C# .NET Core v3.1 with EFCore v3 code explicitly and all works fine.
Except for my Azure Webjob. It listens to a queue. When multiple messages are on the queue and thus the function gets called multiple times in parallel I get transaction errors.
My webjob reads a file from the storage and saves the content to a database table.
I also use the Sharding mechanism: each client has its own database.
I tried using TransactionScope but then I get other errors.
Examples I found use the TransactionScope and opening the connection and doing the saving in one method. I have those parts split into several methods making it unclear to me how to use the TransactionScope.
Here's some code:
ImportDataService.cs:
//using var scope = new TransactionScope(TransactionScopeAsyncFlowOption.Enabled);
await using var tenantContext = await _tenantFactory.GetContextAsync(clientId, true);
await tenantContext.Foo.AddRangeAsync(dboList, cancellationToken);
await tenantContext.SaveChangesAsync(cancellationToken);
//scope.Complete();
TenantFactory.cs:
public async Task<TenantContext> GetContextAsync(int tenantId, bool lazyLoading = false)
{
_tenantConnection = await _sharding.GetTenantConnectionAsync(tenantId);
var optionsBuilder = new DbContextOptionsBuilder<TenantContext>();
optionsBuilder.UseLoggerFactory(_loggerFactory);
if (lazyLoading) optionsBuilder.UseLazyLoadingProxies();
optionsBuilder.UseSqlServer(_tenantConnection,
options => options.MinBatchSize(5).CommandTimeout(60 * 60));
return new TenantContext(optionsBuilder.Options);
}
This code results in SqlConnection does not support parallel transactions.
When enabling TransactionScope I get this error: This platform does not support distributed transactions.
In my ConfigureServices I have
services.AddSingleton<IImportDataService, ImportDataService>();
services.AddTransient <ITenantFactory, TenantFactory>();
services.AddTransient <IShardingService, ShardingService>();
I also tried AddScoped but no change.
Edit: Additional code
ShardingService.cs
public async Task<SqlConnection> GetTenantConnectionAsync(int tenantId)
{
SqlConnection tenantConnection;
try
{
tenantConnection = await _clientShardMap.OpenConnectionForKeyAsync(tenantId, _tenantConnectionString, ConnectionOptions.Validate);
}
catch (Exception e)
{
_logger.LogDebug($"Error getting tenant connection for key {tenantId}. Error: " + e.Message);
throw;
}
if (tenantConnection == null) throw new ApplicationException($"Cannot get tenant connection for key {tenantId}");
return tenantConnection;
}
When the WebJob gets triggered it reads a record from a table. The ID of the record is in the queue message. Before processing the data it first changes the status to processing and when the data is processed it changes the status to processed or error:
var fileImport = await _masterContext.FileImports.FindAsync(fileId);
fileImport.Status = Status.Processing;
await _masterContext.SaveChangesAsync();
if (await _fileImportService.ProcessImportFile(fileImport))
fileImport.Status = Status.Processed;
await _masterContext.SaveChangesAsync();
I'm developing an ASP.NET Web API application with C#, .NET Framework 4.7 and MongoDb.
I have this method:
[HttpPut]
[Route("api/Public/SendCommissioning/{serial}/{withChildren}")]
public HttpResponseMessage SendCommissioning(string serial, bool withChildren)
{
string errorMsg = "Cannot set commissioning.";
HttpResponseMessage response = null;
bool serverFound = true;
try
{
[...]
// Mongo
MongoHelper mgHelper = new MongoHelper();
mgHelper.InsertCommissioning(serial, withChildren);
}
catch (Exception ex)
{
_log.Error(ex.Message);
response = Request.CreateResponse(HttpStatusCode.InternalServerError);
response.ReasonPhrase = errorMsg;
}
return response;
}
Sometimes this method is called very quickly and I get an error here:
// Mongo
MongoHelper mgHelper = new MongoHelper();
mgHelper.InsertCommissioning(serial, withChildren);
Here I'm inserting the serials I received in order, and sometimes I get an error with a duplicated key in MongoDb:
I have a method to get the latest id used in Mongo (the primary key). And two requests get the same id, so when I try to insert it on Mongo I get an invalid key exception.
I thought to use a queue to store the serials and then consume them in the same order that I have received them. But I think I will get the same error when I try to store the serial in MongoDb.
Maybe if I can set a method that if it is running, I have to wait to run it, it will works. This method will have the part of insert the serials into Mongo.
How can I do that? A method that if it is running you can't run it in another Web Api request.
Or, do you know a better option?
By the way, I can't block this method. Maybe I need to run a thread with this synchronized part.
I'm using Entity Framework 5 with MySQL Database and just wanted to update a row attribute "user_loginstatus" between 0 and 1. The first time when I log in via client it updates just fine for the first attempt, after trying to update again it doesn't do anything with no exception.
I log in like this:
public async void LoginExecute()
{
// Checking Connection before etc...
if (await _dataService.IsLoginDataValidTask(UserObj.Username, md5))
{
Trace.WriteLine("LoginCommand Execute: Eingeloggt");
UserObj = await _dataService.GetUserDataTask(UserObj.Username);
await _dataService.SetUserStatusTask(UserObj.Id, 1);
await _dataService.WriteLog(UserObj.Id, "login", "Programm", GetLocalAdress());
Messenger.Default.Send(UserObj);
Messenger.Default.Send(new NotificationMessage("GoToMenuPage"));
}
else
{
// Error Stuff...
}
}
SetUserStatus Method in DataService Class
public Task SetUserStatusTask(int id, int status)
{
return Task.Factory.StartNew(() =>
{
try
{
var user = _entities.users.Find(id);
user.user_loginstatus = status;
_entities.SaveChanges();
}
catch (Exception ex)
{
Trace.WriteLine("DataService SetUserStatusTask: " + ex.Message);
}
});
}
GetUserData Method in DataService Class
public Task<User> GetUserDataTask(string username)
{
return Task.Factory.StartNew(() =>
{
try
{
var user = from us in _entities.users
where us.user_name.Equals(username)
select new User
{
Id = us.user_id,
Username = us.user_name,
FirstName = us.user_firstname,
LastName = us.user_lastname,
Gender = us.user_gender,
Email = us.user_mail,
Group = us.user_usergroup,
Avatar = us.user_avatar,
LoginStatus = 1
};
return user.FirstOrDefault();
}
catch (Exception ex)
{
Trace.WriteLine("DataService GetUserDataTask: " + ex);
return null;
}
});
}
So "users" is my table from the database and "User" / "UserObj" my custom Object.
With the Messenger (from MVVM Light) I just set via MainViewModel the Views, reset the unused ViewModels (ViewModel = new VieModel(...); or ViewModel = null;) and pass the current / logged in User Object.
With the same strategy I just Logout like this
public ICommand LogoutCommand
{
get
{
return new RelayCommand(async () =>
{
await _dataService.SetUserStatusTask(CurrentUser.Id, 0);
if(CurrentUser.Id > 0 && IsLoggedIn)
await _dataService.WriteLog(CurrentUser.Id, "logout", "Programm", GetLocalAdress());
IsLoggedIn = false;
CurrentUser = new User();
Messenger.Default.Send(new NotificationMessage("GoToLoginPage"));
});
}
}
So I can log in with my running Client so often I want, but the "user_loginStatus" only sets the changes the first login time to 1 and back to 0, but when I log out then and login back with the same user, it wont change it anymore. When I login (still same running Client) with another user it sets again the first time the "user_loginstatus" to 1 and back to 0 and then only again when I restart my Client..
What could I do wrong?
This is just basically from my comment regarding the original question:
I had similiar problems several times. Usually it is based on the fact that the entity you modified can't be validated properly and your dbContext fails without a proper exception because it still holds on to false entity. If this is the case you could circumvent this problem by using scoped contexts and embedding your data access operations in a using statement.
Alternatively you could try to explicitly tell EF that the entity has changes e.g.:
_entities.Entry(user).State = EntityState.Modified;
Regarding your other question:
In theory you shouldn't have to tell EF explicitly that the entity's values have changed. Change tracking should do that automatically. The only exception i could think of, is when you try to modify an entity that is explicitly not tracked anymore. When you call _entities.Find(id) it will look in the context if it finds the object with the matching primary key value and load it. Since you already modified this object before, the context will simply get the old object you already modified to set the login status the first time.
This "old" object is probably not tracked anymore and you have to tell EF explicitly that it has changed, by changing it's state from attached to modified.
in LoginExecute() you have UserObj, but in LogoutCommand() you have CurrentUser. Is it OK?
I'm using the example code from http://msdn.microsoft.com/en-us/library/dn631823.aspx to perform the signing in ahead of performing any OneDrive operations. It seemed to work while I was initially coding but now that I've gone back to it after a break, any attempt to (say) read a folder gives me the error:
The access token that was provided has expired.
The code I'm using to log in is:
currentSession = null;
try
{
var authClient = new LiveAuthClient();
LiveLoginResult result = await authClient.LoginAsync(new string[] { "wl.signin", "wl.skydrive" });
if (result.Status == LiveConnectSessionStatus.Connected)
{
currentSession = result.Session;
Debug.WriteLine("... succeeeded");
}
else
Debug.WriteLine("... not connected, status is {0}", result.Status);
}
catch (LiveAuthException ex)
{
// Display an error message.
Debug.WriteLine("LiveAuthException: {0}", ex.Message);
}
catch (LiveConnectException ex)
{
// Display an error message.
Debug.WriteLine("LiveConnectException: {0}", ex.Message);
}
where currentSession is declared as a private variable in the class and it then gets used in the folder code:
LiveConnectClient liveClient = new LiveConnectClient(currentSession);
LiveOperationResult operationResult = await liveClient.GetAsync("me/skydrive");
dynamic result = operationResult.Result;
What is slightly worrying me is that the documentation says:
Create a LiveAuthClient object and call the InitializeAsync method to initialize the Live SDK. Then call the LoginAsync method with the wl.signin and wl.skydrive scopes to enable single sign-in and allow the user to access OneDrive.
but the sample code DOESN'T make any reference to InitializeAsync and there seem to be variations on the call so it isn't really clear which one (if any) I should use.
This is for a Universal App, although currently I'm just working on the WP8.1 C#/XAML part of it. I'm using Live SDK 5.6.
Thanks.
As noted in the comment I added, it looks highly likely that the "expired token" error was being caused by an incorrect date/time setting on the emulator.
I am working on a CRM Dynamics Plugin. There is a field on custom entity named "email". I want to make sure that for two entity records email addresses should be unique. For that purpose I have written following code:
public class Class1 : IPlugin
{
public void Execute(IServiceProvider serviceProvider)
{
// Obtain the execution context from the service provider.
Microsoft.Xrm.Sdk.IPluginExecutionContext context = (Microsoft.Xrm.Sdk.IPluginExecutionContext)
serviceProvider.GetService(typeof(Microsoft.Xrm.Sdk.IPluginExecutionContext));
// Get a reference to the organization service.
IOrganizationServiceFactory factory =
(IOrganizationServiceFactory)serviceProvider.GetService(typeof(IOrganizationServiceFactory));
IOrganizationService service = factory.CreateOrganizationService(context.UserId);
// The InputParameters collection contains all the data passed in the message request.
if (context.InputParameters.Contains("Target") &&
context.InputParameters["Target"] is Entity)
{
Entity entity = (Entity)context.InputParameters["Target"];
//</snippetAccountNumberPlugin2>
// Verify that the target entity represents an account.
// If not, this plug-in was not registered correctly.
if (context.MessageName.ToUpper() == "CREATE")
{
if (entity.LogicalName == "new_assignment1entity")
{
try
{
QueryExpression query = new QueryExpression("new_assignment1entity");
query.ColumnSet.AddColumns("new_email");
EntityCollection result1 = service.RetrieveMultiple(query);
foreach (var a in result1.Entities)
{
int size = result1.Entities.Count;
if (a.Attributes["new_email"].ToString().Equals(entity["new_email"]))
throw new InvalidPluginExecutionException("Duplicate Email found!");
}
}
catch (FaultException<Microsoft.Xrm.Sdk.OrganizationServiceFault>)
{
//You can handle an exception here or pass it back to the calling method.
throw new InvalidPluginExecutionException("Some problem occurred while Querying Records!");
}
}
}
else if (context.MessageName.ToUpper() == "UPDATE")
{
if (entity.LogicalName == "new_assignment1entity")
{
try
{
QueryExpression query = new QueryExpression("new_assignment1entity");
query.ColumnSet.AddColumns("new_email");
EntityCollection result1 = service.RetrieveMultiple(query);
foreach (var a in result1.Entities)
{
int size = result1.Entities.Count;
if (a.Attributes["new_email"].ToString().Equals(entity["new_email"]))
throw new InvalidPluginExecutionException("Duplicate Email found!");
}
}
catch (FaultException<Microsoft.Xrm.Sdk.OrganizationServiceFault>)
{
//You can handle an exception here or pass it back to the calling method.
throw new InvalidPluginExecutionException("Some problem occurred while Querying Records!");
}
}
}
}
}
}
When User creates a new entity record with duplicate email address this code works and shows a dialog box printing error message. But when User edit an existing record (update and existing record) and makes the email address duplicate then this code does not work and updated record with duplicated email address saved.
I am guessing that Context message with UPDATE else part is not working.
Please help me out.
It's not really worth trying to debug this as unfortunately you are going about this in a horribly inefficient way. (Though the most likely cause is the way you are querying being subject to a "feature" of CRM which means you are not querying all the records you think you are).
In short, your code says:
Get me ALL(*) instances of the new_assignment1entity entity
Look at each record until I find one with an email address that matches (case-sensitive) the value just provided in the update
Throw an exception when you encounter the first exact match (otherwise continue with the transaction)
Mains points of note:
QueryExpression will only return the maximum first 5000 records in CRM
You should be filtering your query to only return new_assignment1entity records where the new_email attribute matches the provided value
String.Equals(string) is case-sensitive so to truly check for a duplicate, you should convert the case of each value
Your size variable serves no purpose
Your code will throw an exception if the new/updated record has no value for new_email. You should check that the attribute exists before attempting to access it
I resolved this issue. The problem why only Create execution flow was running and not Update is that I had only registered the plugin for create message step. To overcome this issue, I added a new step in same plugin and registered it with update message as show in following screenshot:
And it worked like charm.
Apart from this, #GregOwens mentioned very helpful points.These should follow as best practices in CRM Development.