Develop Reference

UCMA recording app

I've installed a MSPL script to redirect INVITE audio messages to the UCMA sip address
I'm currently writing a UCMA app for Skype for Business to:
receive incoming calls
accept the call
create a conference call
add a trusted participant to the conference
create a recording instance on the trusted participant audio flow to record the conversation
The last thing I need to do is add the To caller URI to the conference call.
I've tried to invite the new participant into the conference using the code examples from this article, but I get an exception saying there are no AvailableMediaTypes in the conversation.
public static async void InviteToConference(string destinationUri)
{
//Create a new conversation for the application endpoint.
_toConversation = new Conversation(_server.ApplicationEndPoint);
var conferenceInviteSettings = new ConferenceInvitationSettings();
conferenceInviteSettings.ConferenceUri = _conferenceUri;
ConferenceInvitation invitation = new ConferenceInvitation(_toConversation, conferenceInviteSettings);
try
{
await invitation.DeliverAsync(destinationUri);
}
catch (InvalidOperationException)
{
// Conversation was terminated while trying to add participant.
}
}
Can someone please show me what I need to do to add / invite a participant into a conference call?
It would be even better if someone could show me how to record a Skype for Business call without the need to create a conference, as a conference can't be forwarded.

Your code looks like the old way (UCMA 3) of doing it. Have you tried this.
e.g.
McuDialOutOptions mcuDialOutOptions = new McuDialOutOptions();
mcuDialOutOptions.ParticipantUri = "sip:alice#contoso.com";
mcuDialOutOptions.ParticipantDisplayName = "Alice";
mcuDialOutOptions.PreferredLanguage = CultureInfo.GetCultureInfo("en-us");
conversation.ConferenceSession.AudioVideoMcuSession.BeginDialOut("tel:+14255551234", mcuDialOutOptions, dialOutCallback, state);
Using this sort of method to record very specific and low traffic should be fine but when you start to scale it up then you are going to hit all sorts of problems.
As for how to do it without a conference:
There is no way to do it fully with the supplied Microsoft API's.
What you have to do is implement, buy or use open source libraries for the following pieces:
sniff network packets
decode RTP/SRTP streams
decode the audio and/or video codecs used between the callers
encode streams into your desired format and save somewhere
To get access to the SRTP streams encryption setup and to figure out what the dynamic payload types for the audio/video codecs used, you also need to know the SDP offered and answered between the calling parties. You also need access to the SIP traffic to determine the calling parties to know who called who. This can be a lot more trouble than what it seems...
To get the SIP/SDP information there are two options that I know of:
Skype/Lync Server SDK (MSPL / Server Application) to see most of the SIP traffic. This is what I've used to implement a recording solution.
Skype/Lync SDN SDK - I haven't used this API but it seems to give access to the SDP so it should work.
If you get all these peices into place then the next problem is you can only "record" (basically "sniff") what you can see. If you can't see the RTP/SRTP traffic you can't record the calls.
So you need to have the sniffer part of the recording software on areas of the network that see the traffic you want to record. For example if you wish to record all PSTN calls, you can have a network spanning port off the Skype mediation servers.
If you wish to record ALL calls, then that gets a lot harder. You most likely need to either:
Force all media trafic to go through a known place (like the Edge server) and put sniffers on the that network.
Have lots of sniffers in strategic areas of the network to capture most RTP/SRTP traffic.
The problems with the above solutions are:
Forcing all the traffic through one point can cause performance issues (like you will see with your conference setup) once load starts to increase. Also forcing external (edge server users) and/or federated calls through this one point can cause a problems. Think edger server user calls to edge server users where the media traffic may not even go into your network at all but live only on the internet. Forcing the trafficing into your network can cause performance issues.
When not forcing all the traffic through one point, you may never be see all skype user to skype user calls depending on your network setup. Calls between Edge server skype users are even more of a problem as the media traffic may not even enter your network at all.
On top of all that there are the general problems of storage management (recording after a while will start taking up a large amount of disk space) and call recording management (e.g. searching for a specific call) and user security around these recordings to deal with. I'm sure I'm missing a lot but those are the basics.
If recording in not going to be a core component, you could just buy a 3rd party call recording solution that supports Lync/Skype.

In need of some advice controlling a C# winforms application via a asp.net website

I'm working on a little project for a basic Youtube remote control, whereby I have a helper app running on my PC, and then can send commands from a website accessed via the web browser on my phone.
Reading through threads on other sites from people trying to do the same thing I've realized it is not a concept that most people would be comfortable with, but I am struggling to think of another way to do it beyond writing a native app for my phone and having it communicate with the helper application internally via WLAN(Would be happy to do this, but don't have the cash to spring for a new mac to develop for my iphone).
If I were to stick with the Website/Winforms model, is there a way to do this in such a way that (most) people would be comfortable running?
The ideas I had so far were:
a) Build a web server into the helper app(Though not sure of the logistics of having it host an ASP.net site)
b) Host the site externally, and have the helper app periodically poll a database/webservice on a server to receive commands (Sketchy and i imagine very resource heavy)
Sorry for the wall of text, I'm capable of running with an idea and building it, I'm just not sure what is possible and considered the 'best' way to do something like this.
Any advice would be appreciated.
Cheers
Edit Thanks, just to be clear, when i say uncomfortable, I mean - Would you be ok with having a website being able to send potentially ANY command to your computer? This seems to be the problem raised in other discussions about this topic. Obviously I'm not trying to do anything malicious, but as I said, it seemed to be a concern.

If this is a controlled environment where you can always open a port on the firewall for incoming communication, you can have the web app make a WCF call back to the Windows Client through the users firewall.
If not (which is what I suspect), you may be better off polling a web service. Just do it every few seconds and whatever you're checking in that web service call (a database?) make sure it's well optimized. Perhaps just have it return some status int/enum or something very light weight to instruct the client on the next call to make (0 = no update, 1 = command1, 2 = command2, etc).
As for how you do the polling, you could do something like:
int seconds = 4;
System.Timers.Timer _clientTimer = new System.Timers.Timer(seconds * 1000);
_clientTimer.AutoReset = false;
_clientTimer.Elapsed += clientTimer_Elapsed;
_clientTimer.Start();
private void clientTimer_Elapsed(object sender, ElapsedEventArgs e)
{
try
{
// Connect to web service, get status, if status != 0 do something...
}
finally
{
_clientTimer.Start();
}
}
NOTE: the auto-reset = false means that each time the Elapsed event fires, the timer is stopped. In the approach I've taken, I let the timer stop so the client can process the web service results and then start the timer once again after it's done. This will help prevent multiple requests from piling up if a connection is real slow.
That's all I can think of :)

How to resend args to an app if its already running and have it refresh with those args

I have an issue. I'd have a video player that takes in simple parameters as a c# form app. As an experiment to better understand programming, I'd like to have only one instance of the app running and have it refresh with the new args if the open command is given. I could program it so that when it gets the signal, to refreshVideo() or something like that.
Pseudo example:
//app is started from cmd line
//open app for first time
vidViewer.exe("lotr.avi", "44:44");
//keep instance open but have it refresh with new movie
vidViewer.exe("star_wars.avi", "22:32")
As it stands right now a new app with embedded video player will open, so I could have 100 open flicks if I passed it enough args. I'd just like to keep it at one.
Can provide more info if needed.
Thanks all,
Kevin

My suggestion would be to design your application such that, when launched, it would attempt to acquire a system resource that is mutually exclusive (meaning that only the first instance would succeed). Since, in your scenario, you will also require a means of interprocess communication (to transmit the name and start-time of new videos), you may use the same mechanism for achieving this.
You could, for example, use a self-hosted WCF service, bound to a fixed TCP port, that each application instance attempts to register upon being started. Due to the way ports work, only the first instance will succeed; subsequent instances would fail with a “port already in use” exception.
If an instance manages to register the WCF service, then you may assume it to be the “principal” instance and proceed to play the video on it. It should, however, listen for incoming messages from the WCF service and update the video being played accordingly (see below).
If an instance finds that the port is already in use, it should assume that another instance is already running. It would then initialize a WCF client that sends the name and start-time of the new video to be played to the WCF service. Finally, it should terminate itself without displaying any window, assuming that the principal instance will take care of playing its video.

Set service dependencies after install

I have an application that runs as a Windows service. It stores various things settings in a database that are looked up when the service starts. I built the service to support various types of databases (SQL Server, Oracle, MySQL, etc). Often times end users choose to configure the software to use SQL Server (they can simply modify a config file with the connection string and restart the service). The problem is that when their machine boots up, often times SQL Server is started after my service so my service errors out on start up because it can't connect to the database. I know that I can specify dependencies for my service to help guide the Windows service manager to start the appropriate services before mine. However, I don't know what services to depend upon at install time (when my service is registered) since the user can change databases later on.
So my question is: is there a way for the user to manually indicate the service dependencies based on the database that they are using? If not, what is the proper design approach that I should be taking? I've thought about trying to do something like wait 30 seconds after my service starts up before connecting to the database but this seems really flaky for various reasons. I've also considered trying to "lazily" connect to the database; the problem is that I need a connection immediately upon start up since the database contains various pieces of vital info that my service needs when it first starts. Any ideas?

Dennis
what your looking for is SC.exe. This is a command line tool that users can use to configure services.
sc [Servername] Command Servicename [Optionname= Optionvalue...]
more specificly you would want to use
sc [ServerName] config ServiceName depend=servicetoDependOn
Here is a link on the commandlike options for SC.EXE
http://msdn.microsoft.com/en-us/library/ms810435.aspx

A possible (far from ideal) code solution:
In you startup method code it as a loop that terminates when you've got a connection. Then in that loop trap any database connection errors and keep retrying as the following pseudo code illustrates:
bool connected = false;
while (!connected)
{
try
{
connected = openDatabase(...);
}
catch (connection error)
{
// It might be worth waiting for some time here
}
}
This means that your program doesn't continue until it has a connection. However, it could also mean that your program never gets out of this loop, so you'd need some way of terminating it - either manually or after a certain number of tries.
As you need your service to start in a reasonable time, this code can't go in the main initialisation. You have to arrange for your program to "start" successfully, but not do any processing until this method had returned connected = true. You might achieve this by putting this code in a thread and then starting your actual application code on the "thread completed" event.

Not a direct answer put some points you can look into
Windows service can be started Automatically with a delay. You can check this question in SO for some information about it.
How to make Windows Service start as “Automatic (Delayed Start)”
Check this post How to: Code Service Dependencies

Schedule a job in hosted web server

Can some one give me a best way to implement a daily job with .NET technology.
I have an asp.net application with the sqlserver database hosted in shared hosting, GODaddy in my instance.
My application is used to add / change the data in the database which is performing quite fairly at this time.
I got a new requirement to send some email alerts daily based on some data criteria that were stored in the database.
Initially I thought to write a windows service, but godaddy is not allowing to access the database other than its hosted applications.
Does someone has any idea to send alerts daily at 1:00AM?
Thanks in advance

See Easy Background Tasks in ASP.NET by Jeff Atwood.
Copy/paste from the link:
private static CacheItemRemovedCallback OnCacheRemove = null;
protected void Application_Start(object sender, EventArgs e)
{
AddTask("DoStuff", 60);
}
private void AddTask(string name, int seconds)
{
OnCacheRemove = new CacheItemRemovedCallback(CacheItemRemoved);
HttpRuntime.Cache.Insert(name, seconds, null,
DateTime.Now.AddSeconds(seconds), Cache.NoSlidingExpiration,
CacheItemPriority.NotRemovable, OnCacheRemove);
}
public void CacheItemRemoved(string k, object v, CacheItemRemovedReason r)
{
// do stuff here if it matches our taskname, like WebRequest
// re-add our task so it recurs
AddTask(k, Convert.ToInt32(v));
}

I haven't used GoDaddy for anything other than domain registration, so I have no experience with what you can or cannot do on their hosting platform. I also don't know what their support or knowledge base is like, but I'd say your best option is to ask GoDaddy what they recommend. Otherwise, you might keep implementing something that's technically feasible, but is blocked by the hosting company.
If it's not something that's a prime-time application, one quick and dirty thing to do is to have some kind of external bot calling a (secure) web page on the server that fires off the notification process. Not a real solution, but if this site is just a hobby of yours, it could get you by until you find something the host will allow.
Might also be a good time to find a new host, if this one is not meeting your requirements. There are lots of good ASP.NET hosts available these days.

You can use windows scheduler from the web server to schedule a stored procedure call that can send mail based on particular criteria.
osql.exe -S servername -d database -U username -P password -Q "EXEC spAlertOnCriteria"
References:
osql
Task Scheduler

Many hosting providers can request a URL for you every X minutes. I don't know if GoDaddy does, but if so, you could create an ASMX page that kicks off the job, and tell them to execute it automatically.
If they don't, one solution might be to fire off the job in a background thread at every page request. If you do that, make sure you put in code that limits it to running every X minutes or more (perhaps using a static variable or a database table) - read this story

If you can expose a service on the website hosting the application and database -- authenticated service, of course -- then you can hit that service remotely from any box with credentials, pull down the data, and send the mail that way.
This could be an automated process written as a Windows service, an application that is run under the Scheduler, or some button you push at 1:00 AM. Your pick.
Just because the app is the only thing that can access the database doesn't mean you can't expose the data in other ways.

Use either System.Timers, System.Threading to create a instance that is run at a predetermined time. Have that thread execute whatever the task is that you want... Make sure the code is thread safe!