So I have a remote table called Profile that has multiple entries made already. Now I'm trying to integrate offline capabilities into my application. As of right now I'm having issues with PushAsync and PullAsync methods in my code.
I would like to be able to copy all the data from my remote table into my local table just by calling PullAsync, and although it doesn't throw any exceptions it also doesn't populate my table. Here's an example of what I mean.
var db = new SQLiteConnection("syncstoreTEMP.db");
var store = new MobileServiceSQLiteStore("syncstoreTEMP.db");
store.DefineTable<Profile>();
MobileService.SyncContext.InitializeAsync(store).Wait();
var remoteValues = MobileService.GetTable<Profile>()
.ToListAsync()
.Result;
MobileService.GetSyncTable<Profile>()
.PullAsync(null, MobileService.GetSyncTable<Profile>().CreateQuery())
.Wait();
var localValues = MobileService.GetSyncTable<Profile>()
.ToListAsync()
.Result;
When I run this code remoteValues has a total length of 5, but localValues still shows 0 entries even after issuing a Pull from remote. How can I get the sync table to match my remote table?
It's strange that you're not getting any exceptions, but you seem to be creating two connections to your local store. You should not have the line for new SQLiteConnection, only the line that creates the MobileServiceSQLiteStore.
Here's a tutorial that walks through how to set things up: https://azure.microsoft.com/en-us/documentation/articles/mobile-services-xamarin-ios-get-started-offline-data/
I also recommend that you add a DelegatingHandler to your MobileServiceClient in order to log all of the requests and responses. Then you can see exactly what's going wrong. Here's a sample that shows this, and also includes a logging extension to the SQLite store so you can see exactly what is happening locally: https://github.com/paulbatum/FieldEngineerLite/blob/master/FieldEngineerLite.Client/FieldEngineerLite/Helpers/LoggingHelpers.cs
Related
I'm new to Realm Sync (and Realm). I'm trying to convert a REST / SQL Server system to Realm Sync (to avoid having to write my own local-device caching code).
I got a simple configuration working, with a single API-key user and the null partition, read and write permissions just set to true.
But for my more complex application, I want smaller sub-partitions to reduce the amount of data that needs to be cached on local devices, and I want the sub-partitions to be able to be created dynamically by the client. Ideally, I would like to allow an API-key user to connect to any partition whose name starts with their user id (or some other known string, e.g. the profile name). But I can't find a way to get a "starts with" condition into the permissions.
My best attempt was to try setting Read and Write sync permissions to:
{
"%%partition": {
"$regex": "^%%user.id"
}
}
but my client just fails to connect, saying Permission denied (BIND, REFRESH). (Yes, I tried using "$regex": /^%%user.id/ but the Realm UI rejected that syntax.) The Realm Sync log says "user does not have permission to sync on partition (ProtocolErrorCode=206)".
As you can see in the log image, the partition name was equal to the user id for this test.
Is what I'm trying to do possible? If so, how do I set up the Sync Permissions to make it work?
This can be done using a function. If, like me, you're new to Realm Sync and not fluent in Javascript, don't worry - it turns out to be not too hard to do, after all. (Thanks Jay for encouraging me to try it!)
I followed the instructions on the Define a Function page to create my userCanAccessPartition function like this:
exports = function(partition){
return partition.startsWith(context.user.id);
};
Then I set my sync permissions to:
{
"%%true": {
"%function": {
"name": "userCanAccessPartition",
"arguments": ["%%partition"]
}
}
}
I need to create subdomains in Azure DNS from ASP.NET Core dynamically so that the users who needs to create their own subdomains can do it as we see in most of the web apps out there like wix, etc..
Could anyone please detail the right steps well explained?
Thanks.
There is a management SDK for Azure, which you can use inside your ASP.NET Core application.
Create DNS zones and record sets using the .NET SDK - this is detailed full tutorial for this.
Code will be similar to this, though you will probably use CNAMEs instead of A records
// Create record set parameters
var recordSetParams = new RecordSet();
recordSetParams.TTL = 3600;
// Add records to the record set parameter object. In this case, we'll add a record of type 'A'
recordSetParams.ARecords = new List<ARecord>();
recordSetParams.ARecords.Add(new ARecord("1.2.3.4"));
// Add metadata to the record set. Similar to Azure Resource Manager tags, this is optional and you can add multiple metadata name/value pairs
recordSetParams.Metadata = new Dictionary<string, string>();
recordSetParams.Metadata.Add("user", "Mary");
// Create the actual record set in Azure DNS
// Note: no ETAG checks specified, will overwrite existing record set if one exists
var recordSet = await dnsClient.RecordSets.CreateOrUpdateAsync(resourceGroupName, zoneName, recordSetName, RecordType.A, recordSetParams);
I created application using CRM 2011 SDK.
While retrieving audit record i use recommended code.
My code looks like this:
using (_serviceProxy = ServerConnection.GetOrganizationProxy(serverConfig))
{
_service = (IOrganizationService)_serviceProxy;
RetrieveRecordChangeHistoryRequest changeRequest = new RetrieveRecordChangeHistoryRequest();
changeRequest.Target = new EntityReference(Static.IncidnentsEntityName, new Guid(id));
RetrieveRecordChangeHistoryResponse changeResponse =
(RetrieveRecordChangeHistoryResponse)_service.Execute(changeRequest);
return changeResponse.AuditDetailCollection.AuditDetails.SelectMany(s => createAuditRecord(s)).ToList();
}
where createAuditRecord function just unpacks attributes. There is an attribute called userid, but it always returns system user, under which my app is calling CRM, but not the logged user.
While directly querying SQL ,I've found that there is an information about logged user.
Is there some way to extract this information without directly extracting data from DB?
I prefer to extract information directly from database if it's for external use or reports. It's much faster, you can do complexier queries and you will save a lot of time. There no plus value of using the SDK to read data other than being sure it gonna be supported in the next version and supported online.
I want to pull documents with username attribute
as user1 for user1 like that for each user only attribute with their name.
This is my replication code.
private void setupreplication(){
Console.WriteLine ("Setting up replication");
Uri Server = new Uri("http://192.168.1.213:4984/aussie-coins-syncgw/");
var pull = _db.CreatePullReplication (Server);
var push = _db.CreatePushReplication (Server);
pull.Filter = "byUser";
pull.FilterParams = new Dictionary<string, object> { {"type", "user1"} };
pull.Continuous = true;
push.Continuous = true;
pull.Start();
push.Start();
}
This is my set filter code
_couchBaseLiteLocal.SetFilter("byUser", (revision, filterParams) =>
{
var typeParam = filterParams["type"].ToString();
return (typeParam != null) && typeParam.Equals("user1");
});
With the above code generic pull itself not working.
I just tried to do as given in the documentation.
I do not understand how the setfilter function works to filter data from server. It would be great if someone help in understanding how setfilter works and to make the above code working
Thanks in advance.
The filter function in pull replications can indeed return the specific documents you are interested in. But it's not very efficient, the filter function will run on all the documents on the remote database to determine which ones to pull, every time a pull replication is started.
Instead Sync Gateway introduces the concept of a sync function that incrementally routes and computes access control rules on documents. That way, when starting the pull replication, it's fast and straightforward for Sync Gateway to return the specific documents the user has access to.
You can specify individual channels in a pull replication from Sync Gateway if needed. But the thing to remember is that filtered pull replication between Sync Gateway and Couchbase Lite is not based on filter functions. It's based on the sync function and channel based filtering if needed.
In a P2P scenario (replications between two Couchbase Lite instances), the filter function model is used.
I have a webpage that uses ajax polling to get stock market updates from the server. I'd like to use SignalR instead, but I'm having trouble understanding how/if it would work.
ok, it's not really stock market updates, but the analogy works.
The SignalR examples I've seen send messages to either the current connection, all connections, or groups. In my example the stock updates happen outside of the current connection, so there's no such thing as the 'current connection'. And a user's account is associated with a few stocks, so sending a stock notification to all connections or to groups doesn't work either. I need to be able to find a connection associated with a certain userId.
Here's a fake code example:
foreach(var stock in StockService.GetStocksWithBigNews())
{
var userIds = UserService.GetUserIdsThatCareAboutStock(stock);
var connections = /* find connections associated with user ids */;
foreach(var connection in connections)
{
connection.Send(...);
}
}
In this question on filtering connections, they mention that I could keep current connections in memory but (1) it's bad for scaling and (2) it's bad for multi node websites. Both of these points are critically important to our current application. That makes me think I'd have to send a message out to all nodes to find users connected to each node >> my brain explodes in confusion.
THE QUESTION
How do I find a connection for a specific user that is scalable? Am I thinking about this the wrong way?
I created a little project last night to learn this also. I used 1.0 alpha and it was Straight forward. I created a Hub and from there on it just worked :)
I my project i have N Compute Units(some servers processing work), when they start up they invoke the ComputeUnitRegister.
await HubProxy.Invoke("ComputeUnitReqisted", _ComputeGuid);
and every time they do something they call
HubProxy.Invoke("Running", _ComputeGuid);
where HubProxy is :
HubConnection Hub = new HubConnection(RoleEnvironment.IsAvailable ?
RoleEnvironment.GetConfigurationSettingValue("SignalREndPoint"):
"http://taskqueue.cloudapp.net/");
IHubProxy HubProxy = Hub.CreateHubProxy("ComputeUnits");
I used RoleEnviroment.IsAvailable because i can now run this as a Azure Role , a Console App or what ever in .NET 4.5. The Hub is placed in a MVC4 Website project and is started like this:
GlobalHost.Configuration.ConnectionTimeout = TimeSpan.FromSeconds(50);
RouteTable.Routes.MapHubs();
public class ComputeUnits : Hub
{
public Task Running(Guid MyGuid)
{
return Clients.Group(MyGuid.ToString()).ComputeUnitHeartBeat(MyGuid,
DateTime.UtcNow.ToEpochMilliseconds());
}
public Task ComputeUnitReqister(Guid MyGuid)
{
Groups.Add(Context.ConnectionId, "ComputeUnits").Wait();
return Clients.Others.ComputeUnitCameOnline(new { Guid = MyGuid,
HeartBeat = DateTime.UtcNow.ToEpochMilliseconds() });
}
public void SubscribeToHeartBeats(Guid MyGuid)
{
Groups.Add(Context.ConnectionId, MyGuid.ToString());
}
}
My clients are Javascript clients, that have methods for(let me know if you need to see the code for this also). But basicly they listhen for the ComputeUnitCameOnline and when its run they call on the server SubscribeToHeartBeats. This means that whenever the server compute unit is doing some work it will call Running, which will trigger a ComputeUnitHeartBeat on javascript clients.
I hope you can use this to see how Groups and Connections can be used. And last, its also scaled out over multiply azure roles by adding a few lines of code:
GlobalHost.HubPipeline.EnableAutoRejoiningGroups();
GlobalHost.DependencyResolver.UseServiceBus(
serviceBusConnectionString,
2,
3,
GetRoleInstanceNumber(),
topicPathPrefix /* the prefix applied to the name of each topic used */
);
You can get the connection string on the servicebus on azure, remember the Provider=SharedSecret. But when adding the nuget packaged the connectionstring syntax is also pasted into your web.config.
2 is how many topics to split it about. Topics can contain 1Gb of data, so depending on performance you can increase it.
3 is the number of nodes to split it out on. I used 3 because i have 2 Azure Instances, and my localhost. You can get the RoleNumber like this (note that i hard coded my localhost to 2).
private static int GetRoleInstanceNumber()
{
if (!RoleEnvironment.IsAvailable)
return 2;
var roleInstanceId = RoleEnvironment.CurrentRoleInstance.Id;
var li1 = roleInstanceId.LastIndexOf(".");
var li2 = roleInstanceId.LastIndexOf("_");
var roleInstanceNo = roleInstanceId.Substring(Math.Max(li1, li2) + 1);
return Int32.Parse(roleInstanceNo);
}
You can see it all live at : http://taskqueue.cloudapp.net/#/compute-units
When using SignalR, after a client has connected to the server they are served up a Connection ID (this is essential to providing real time communication). Yes this is stored in memory but SignalR also can be used in multi-node environments. You can use the Redis or even Sql Server backplane (more to come) for example. So long story short, we take care of your scale-out scenarios for you via backplanes/service bus' without you having to worry about it.