I'm developing a class library that contains generic methods for these scenarios:
Live support chat (1 on 1 private text chat, with many admins and guests)
Rooms with many users where you can send broadcast and private messages
These two features above are already implemented and now it's necessary for my application to save messages.
My question is, what is the best way to store chat conversations in a SQL database:
Everytime I click send, I insert the message in the database?
Create a List for each user and everytime I click send, the message is saved on the list of the user who sent the message. Then if a user disconnects, I'm going to iterate the list of messages and for each message insert all of them in the db.
Are there other solutions?
What I'm doing now is the following. I have this method which is located on my Hub class:
public void saveMessagetoDB(string userName, string message)
{
var ctx = new TestEntities1();
var msg = new tbl_Conversation {Msg = message};
ctx.tbl_Conversation.Add(msg);
ctx.SaveChanges();
}
I call this method saveMessagetoDB on my client side HTML file like this:
$('#btnSendMessage').click(function () {
var msg = $("#txtMessage").val();
if (msg.length > 0) {
var userName = $('#hUserName').val();
// <<<<<-- ***** Return to Server [ SaveMessagetoDB ] *****
objHub.server.saveMessagetoDB(userName, msg);
SignalR is great for a chat application and you wouldn't even need to store anything in SQL unless you want to create a transcript of the chat at a later time (which may not even be necessary).
I suggest getting the chat working with SignalR first (don't do anything with sql). Then once that is working you can put SQL logging as necessary in your signalR hub.
It most likely makes the most sense to write to sql on each message.
If you decide to store the chats in a database, then you will need to insert/update the messages as they happen.
If you are using the PersistentConnection then you can hook into the OnReceivedAsync event and insert / update data from that event:
protected override Task OnConnectedAsync(IRequest request, string connectionId)
{
_clients.Add(connectionId, string.Empty);
ChatData chatData = new ChatData("Server", "A new user has joined the room.");
return Connection.Broadcast(chatData);
}
Or in the SignalR class that inherits from Hub, you can persist to the Db right before you have notified any clients.
Related
in application.properties I need to set the OAuth2 keys...
OAuth2AppClientId=AB............................AN
OAuth2AppClientSecret=br................................u8
OAuth2AppRedirectUri=http://localhost:8085/oauth2redirect
Initially I put the keys in "" quotes assuming they should be treated as a string but to get it working I had to remove them. Can someone explain what's happening with
OAuth2AppClientId=AB............................AN when I build the app
and how do I find out more about OAuth2AppClientId?
A Google search is probably the place to start here. Here's a great resource about what a Client ID and Client Secret are:
https://www.oauth.com/oauth2-servers/client-registration/client-id-secret/
I quote:
The client_id is a public identifier for apps.
The client_secret is a secret known only to the application and the authorization server.
Intuit also has a ton of documentation on OAuth2, and how to implement it. You should read it:
https://developer.intuit.com/app/developer/qbo/docs/develop/authentication-and-authorization/oauth-2.0
In summary, the Client ID is how Intuit identifies that it's your app trying to connect to QuickBooks. Nothing is "happening" to the string when you build/compile the app - it's just normal string. But when your app authenticates against QuickBooks Online, your app sends the Client ID to QuickBooks so that QuickBooks knows it's your app trying to authorize a connection to QuickBooks, and not some other app.
If you want to see how to code is loading this, it is only a property being used inside the application
OAuth2PlatformClientFactory
#Service
#PropertySource(value="classpath:/application.properties", ignoreResourceNotFound=true)
public class OAuth2PlatformClientFactory {
#Autowired
org.springframework.core.env.Environment env;
OAuth2PlatformClient client;
OAuth2Config oauth2Config;
#PostConstruct
public void init() {
// intitialize a single thread executor, this will ensure only one thread processes the queue
oauth2Config = new OAuth2Config.OAuth2ConfigBuilder(env.getProperty("OAuth2AppClientId"), env.getProperty("OAuth2AppClientSecret")) //set client id, secret
.callDiscoveryAPI(Environment.SANDBOX) // call discovery API to populate urls
.buildConfig();
client = new OAuth2PlatformClient(oauth2Config);
}
public OAuth2PlatformClient getOAuth2PlatformClient() {
return client;
}
public OAuth2Config getOAuth2Config() {
return oauth2Config;
}
public String getPropertyValue(String propertyName) {
return env.getProperty(propertyName);
}
}
https://github.com/IntuitDeveloper/OAuth2-JavaWithSDK/blob/master/src/main/java/com/intuit/developer/sampleapp/oauth2/client/OAuth2PlatformClientFactory.java
Have hard time to get push notifications from server when using MSSQL scalling.
Message flow is one way from server to subscribers (are distributed by groups)
Push messages are not received on UI with the following host configuration:
GlobalHost.DependencyResolver.UseSqlServer(new SqlScaleoutConfiguration(ConfigurationManager.ConnectionStrings["SignalR"].ConnectionString));
Messages are created in SignalRDb and records are present in tables. However they do not reach UI. With SQL scaling disabled all messages propagates to UI successfully.
Here is my Notification code:
public void OnNext(ResultModel value)
{
Clients.Group(group).notify(value);
}
OnNext method always executes witho or without Scalling also group and value are correct. No exceptions thrown on UI or beckend. Below is UI part:
var hubProxy = $.connection.visitsHub;
hubProxy.client.notify = function (updatedResult) {
console.log(updatedResult.Id);
});
};
Any help is appreciated.
I'm trying to implement pagination using App Engine's RPC and GWT (it's an app engine connected project).
How can I pass both the query results and the web-safe cursor object to the GWT client from the RPC?
I've seen examples using a servlet but I want to know how to do it without a servelt.
I've considered caching the cursor on the server using memcache but I'm not sure if that's appropriate or what should be used as the key (session identifier I would assume, but I'm not sure how those are handled on App Engine).
Links to example projects would be fantastic, I've been unable to find any.
OK, so the best way to do this is to store the cursor as a string on the client.
To do this you have to create a wrapper class that is transportable so you can pass back it to the client via RequestFactory that can hold the results list and the cursor string. To do that you create a normal POJO and then a proxy for it.
here's what the code looks like for the POJO:
public class OrganizationResultsWrapper {
public List<Organization> list;
public String webSafeCursorString;
public List<Organization> getList() {
return list;
}
public void setList(List<Organization> list) {
this.list = list;
}
public String getWebSafeCursorString() {
return this.webSafeCursorString;
}
public void setWebSafeCursorString(String webSafeCursorString) {
this.webSafeCursorString = webSafeCursorString;
}
}
for the proxy:
#ProxyFor(OrganizationResultsWrapper.class)
public interface OrganizationResultsWrapperProxy extends ValueProxy{
List<OrganizationProxy> getList();
void setList(List<OrganizationProxy> list);
String getWebSafeCursorString();
void setWebSafeCursorString(String webSafeCursorString);
}
set up your service and requestFactory to use the POJO and proxy respectively
// service class method
#ServiceMethod
public OrganizationResultsWrapper getOrganizations(String webSafeCursorString) {
return dao.getOrganizations(webSafeCursorString);
}
// request factory method
Request<OrganizationResultsWrapperProxy> getOrganizations(String webSafeCursorString);
Then make sure and run the RPC wizard so that your validation process runs otherwise you'll get a request context error on the server.
Here's the implementation in my data access class:
public OrganizationResultsWrapper getOrganizations(String webSafeCursorString) {
List<Organization> list = new ArrayList<Organization>();
OrganizationResultsWrapper resultsWrapper = new OrganizationResultsWrapper();
Query<Organization> query = ofy().load().type(Organization.class).limit(50);
if (webSafeCursorString != null) {
query = query.startAt(Cursor.fromWebSafeString(webSafeCursorString));
}
QueryResultIterator<Organization> iterator = query.iterator();
while (iterator.hasNext()) {
list.add(iterator.next());
}
resultsWrapper.setList(list);
resultsWrapper.setWebSafeCursorString(iterator.getCursor().toWebSafeString());
return resultsWrapper;
}
a second option would be to save the webSafeCursorString in the memcache, as you already mentioned.
my idea looks like this:
the client sends always request like this "getMyObjects(Object... myParams, int maxResults, String clientPaginationString)". the clientPaginationString is uniquely created like shown below
server receives request and looks into the memcache if there is a webSafeCursorString for the key clientPaginationString
if the server finds nothing, he creates the query and save the webSafeCursorString into memcache with the clientPaginationString as the key. -> returns the results
if the server finds the webSafeCursorString he restarts the query with it and returns the results
the problems are how to clean the memcache and how to find a unique clientPaginationString:
a unique clientPaginationString should be the current UserId + the params of the current query + timestemp. this should work just fine!
i really can't think of a easy way how to clean the memcache, however i think we do not have to clean it at all.
we could store all the webSafeCursorStrings and timestemps+params+userid in a WebSafeCursor-Class that contains a map and store all this in the memcache... and clean this Class ones in a while (timestamp older then...).
one improvement i can think of is to save the webSafeCursorString in the memcache with a key that is created on the server (userSessionId + servicename + servicemethodname + params). however, important is that the client sends an information if he is interested in a new query (memcache is overriden) or wants the next pagination results (gets webSafeCursorString from memcache). a reload of the page should work. a second tap in the browser would be a problem i think...
what would you say?
I have silver light application.in the client side i have list of Guid using that Guid i can retrieve all data of customer when i am selecting 26 clients it works fine but when i tried to accessed data more then 26 clients it gives me error like
Load Opration failed for query GetAtclientsERCWithAllInformation the remote server not found
my client side look like
var query = formscontext.GetATClientsERCWithAllInformationQuery(guid);
try
{
LoadOperation<ATClient> _loadReturnTypeOperation = formscontext.Load(query);
_loadReturnTypeOperation.Completed += (s, e) =>
{
some code goes here
}
my server side look like
[Query(HasSideEffects=true)]
public IQueryable<ATClient> GetATClientsERCWithAllInformation(List<Guid> clientsGuids)
{
return this.ObjectContext.ATClients.Include("ClientEfileInfo").Include("ATClientImages").Include("ATPreparer").Include("ATPreparer.ATFirm").Include("ATClientReturns")
.Include("ATClientReturns.ATForms").Include("ATClientReturns.ATForms.FormsMaster").Where(p => clientsGuids.Contains(p.ClientGUID));
}
It seems that EF can't handle the query you requested. The error that silverlight is reporting is useless, you should look into the http response (remember that from an http perspective you're just doing a POST).
Override the
protected override void OnError(DomainServiceErrorInfo errorInfo)
on your domainservice class in order to get the real error. Another quick way to get the error is to setup an http proxy and inspect the response (you can use fiddler + wcf binary inspector from msdn)
UPDATE: The plot thickens. I changed my channel name and it is suddenly working (which means it wasn't a problem with my push service, since I'm getting the same HTTP response from the Microsoft Push Notification server).
To me, however, this is not a solution. How will I be able to test this and KNOW my users are getting their push notifications if I'm getting the same response when it's not working as I do when it is?
[ORIGINAL POST]
I've been trying to get push notifications sent to my Windows Phone 7 device, but I'm having very big problems that I can't find any answers for. I'll start with the c# code.
I set up push notifications using the following C# code.
private HttpNotificationChannel channel;
private static string PUSH_CHANNEL = "MySpecialPushChannel";
private Uri PushUri = null;
private bool IsPushRegistered = false;
public void StartPushSubscription()
{
try
{
channel = HttpNotificationChannel.Find(PUSH_CHANNEL);
}
catch
{}
if (channel != null)
{
PushUri = channel.ChannelUri;
if (!channel.IsShellTileBound)
channel.BindToShellTile();
}
else
{
channel = new HttpNotificationChannel(PUSH_CHANNEL);
channel.ChannelUriUpdated += new EventHandler<NotificationChannelUriEventArgs>(channel_ChannelUriUpdated);
channel.HttpNotificationReceived += new EventHandler<HttpNotificationEventArgs>(channel_HttpNotificationReceived);
channel.ErrorOccurred += new EventHandler<NotificationChannelErrorEventArgs>(channel_ErrorOccurred);
try
{
channel.Open();
channel.BindToShellTile();
}
catch (Exception err)
{
channel = null;
IsPushRegistered = false;
// Code to try again
}
}
}
void channel_ChannelUriUpdated(object sender, NotificationChannelUriEventArgs e)
{
PushUri = e.ChannelUri;
IsPushRegistered = true;
}
I'm following the standard WP7 push structure:
Find the HttpNotificationChannel (or start a new one)
Register event handler to get the push notification uri back
Open the channel
Bind to the tile
Handle the channel Uri (which we send to our service to await the happy day when we send the push notification
OK... so far so good. No errors, I get my Uri, send it to my service just fine. I pin my app to the start screen and my service sends a push request to the Uri (sending just the count so that I get a little push count number in the upper right hand corner). I get back an HTTP 200 status with the following:
DeviceConnectionStatus => Connected
NotificationStatus => Received
SubscriptionStatus => Active
And then... nothing. No push status shows up on my app. I've now tried it on my device, in the emulator, on another device, and with multiple servers and the result is always the same. Everything looks like it is working except for the fact that it doesn't work.
To me, however, this is not a solution. How will I be able to test this and KNOW my users are getting their push notifications if I'm getting the same response when it's not working as I do when it is?
The answer is, you can't. It's a limitation of how WP7 handles notifications.
For structured notifications like Tile and Toast, if you get the Connected/Active/Received/200 response, then you can know that MPNS accepted your notification request. However, this does not mean that you have sent a valid XML payload.
The component that handles parsing XML is the Push Client, the process running on the phone that accepts push notifications and deals them out to appropriate applications, displays the toast, etc.
If you have sent invalid XML, there is absolutely no indication that you've done so. At most, if you try to send the notification again to that same push channel URI, you'll get a 404 in response. Apparently getting an invalid XML payload for a specific application makes that application's push channel close, requiring you to go through the whole procedure again.
I've discovered this while debugging with our server team, and through trying to get the phone to display an alternate live tile. The only advice I can offer you is to quadruple-check your XML.
You will get errors in your error event handler for your push notification channel for Toast notifications that have invalid XML, since you are able to send/receive toast notifications while the application is active.
If anyone from Microsoft is reading this, PLEASE provide more thorough documentation on possible error states in the push notification system. We also need an event handler for Tile notifications, or at least allow us to receive tile notifications while the app is in the foreground and fire the notification channel error event so that we can be aware that our XML payload is invalid.
Especially if your web service isn't built with WCF, .NET, Azure, and whatever, working with Push Notifications on WP7 is like wandering blind.
Documentation for an exception message reading "InvalidOperationException(Failed to open channel)" should not read: "This exception is raised when the notification channel failed to open. Try opening the notification channel again." (reference)
are you getting the URL from each device? you need to get a URL from the push notification sevice for each device everytime your device connects,
when it does you need to find a way of retrieving the url from each client,
once you do that and your still not receiving push notifications then I would write to microsoft to see if they can see anything to do with the push notifications