2005 2006 2007 2008 2009 2010 2011 2015 2016 2017 aspnet azure csharp debugging elasticsearch exceptions firefox javascriptajax linux llblgen mongodb powershell projects python security services silverlight training videos wcf wpf xag xhtmlcss

Video 3 (FWD) - "Introduction to the Firefox Console"

Here's the next video in the Firefox Web Developer series: Using the Firefox Console. The Firefox Console is a tremendously underused tool built right into Firefox. It allows for safe and efficient JavaScript development that may otherwise be a complete nightmare. This tool is also an absolute must for remote scripting developers (yes, I still refuse to call it "Ajax"). You can think of this tool as being much like a service tracer. C# programmers will feel right at home with this guy.

I say it in the video as well, but let me emphasis it here: the Firefox console is not the JavaScript console. Firefox is a complete standalone Web Development Suite -- not just a web browser. These tools are not addons, plugins, or extensions, but rather are natively built-in tools in Firefox. In later videos I will discuss other tools also built right into Firefox.

OK, so here ya go...

WCF Relative Binding Speeds

My latest infrastructure design consists of a few services spread over various servers and with many clients in various locations. Some of the clients will be on the same machine as the service, others will be on the same NT-based network, others will be WSE3 services, and even others will be PHP based. I wanted to provide the best solution for each, ergo my love for the Go-live of WCF! With WCF I can have the services expose multiple endpoints to allow a diverse number of clients each with their own maximum efficiency (remember, if you aren't measuring, then you aren't engineering!) PHP clients for example will get a BasicHttpBinding endpoint, while clients on the same machine as the service will use the NetNamedPipeBinding.

What do the speeds look like for each of these bindings? I went ahead and wrote a quick test harness to see the relative speeds of each binding. These are very simple tests, but they do demonstrate how the speeds of the bindings compare with each other. Without a ton of needless talk, let's get right into what's going on...

Here is the service configuration file...

  <system.serviceModel>
    <services>
      <service type="WcfDemo.DemoService">
        <endpoint
          address="WsDualHttpBinding"
          contract="WcfDemo.IDemoService"
          binding="wsDualHttpBinding"
          />
        <endpoint
          address="WsHttpBinding"
          contract="WcfDemo.IDemoService"
          binding="wsHttpBinding"
          />
        <endpoint
          address="BasicHttpBinding"
          contract="WcfDemo.IDemoService"
          binding="basicHttpBinding"></endpoint>
        <endpoint
          address="NetTcpBinding"
          contract="WcfDemo.IDemoService"
          binding="netTcpBinding"
          />
        <endpoint
          address="NetNamedPipeBinding"
          contract="WcfDemo.IDemoService"
          binding="netNamedPipeBinding"></endpoint>
      </service>
    </services>
  </system.serviceModel>

Here is the significant portion of the service code...

Uri netTcpAddress = new Uri("net.tcp://localhost:8080/");
Uri httpAddress = new Uri("http://localhost:8081/");
Uri netPipeAddress = new Uri("net.pipe://localhost/");
using (ServiceHost service = new ServiceHost(typeof(DemoService), new Uri[] { netTcpAddress, httpAddress, netPipeAddress })) {
        service.Open( );

        Console.WriteLine("Listening...");
        Console.ReadLine( );
}

Notice the netPipeAddress is using "net.pipe" as the address scheme and doesn't have a port. This is actually for the netNamedPipeBinding binding which is for inner process communication on the same machine, so there wouldn't be a port for that. The netTcpBinding binding does however have a port as it would really be out on the network somewhere. Also keep in mind that you add a URI for each address scheme, not each address.

Here is the client configuration file...

<system.serviceModel>
    <client>
      <endpoint
        address="http://localhost:8081/WsDualHttpBinding"
        binding="wsDualHttpBinding"
        name="WSDualHttpBinding"
        contract="IDemoService" />
      <endpoint
        address="http://localhost:8081/WsHttpBinding"
        binding="wsHttpBinding"
        name="WSHttpBinding"
        contract="IDemoService" />
      <endpoint
        address="http://localhost:8081/BasicHttpBinding"
        binding="basicHttpBinding"
        name="BasicHttpBinding"
        contract="IDemoService" />
      <endpoint
        address="net.tcp://localhost:8080/NetTcpBinding"
        binding="netTcpBinding"
        name="NetTcpBinding"
        contract="IDemoService" />
      <endpoint
        address="net.pipe://localhost/NetNamedPipeBinding"
        binding="netNamedPipeBinding"
        name="NetNamedPipeBinding"
        contract="IDemoService" />
    </client>
  </system.serviceModel>

Again notice there is no port on the netNamedPipeBinding binding and there is a port on the netTcpBinding. Also notice that each of the addresses end in the name of the endpoint specified by the server; the endpoints also have a name attribute to be accessible by the client-side code as seen in the next code block.

Here is how I start my client code...

DemoServiceClient wSDualHttpClient = new DemoServiceClient("WSDualHttpBinding");
DemoServiceClient wSHttpClient = new DemoServiceClient("WSHttpBinding");
DemoServiceClient basicHttpClient = new DemoServiceClient("BasicHttpBinding");
DemoServiceClient netTcpClient = new DemoServiceClient("NetTcpBinding");
DemoServiceClient netNamedPipeClient = new DemoServiceClient("NetNamedPipeBinding");

My actual benchmarking code consists of a simple timer that look like this...

Person person = new Person( );
DateTime a = DateTime.Now;
int i = 0;
while ((DateTime.Now - a).Seconds < 10) {
    wSDualHttpClient.RecordPerson(person);
    i++;
}
Console.WriteLine("WSDualHttpBinding: Processed  calls in 10 seconds", i);

That basically just means I want to run as many tests as possible in 10 seconds.

I actually ordered the tests based on my predictions of their relative speeds and it turns out my predictions were correct. Take a look for yourself...

WSDualHttpBinding: Processed 1602 calls in 10 seconds
WSHttpBinding: Processed 2531 calls in 10 seconds
BasicHttpBinding: Processed 17913 calls in 10 seconds
NetTcpBinding: Processed 39957 calls in 10 seconds
NetNamedPipeBinding: Processed 48255 calls in 10 seconds

This isn't really that surprising. The more complex web services protocols are slower than the most basic ones, which are in turn slower than a direct TCP connection, which in turn is slower than the named-pipes binding connection for use on the same machine.  So, if you are going to be doing something chatty, you may want to think twice before using SOAP.

That was actually an out-of-the-box benchmark; that is, I didn't customize the bindings in any way. In another test I turned off security for the WsDualHttpBinding and WsHttpBinding bindings.

First, I added the following binding sections to both the service and the client configuration files.

<bindings>
  <wsDualHttpBinding>
    <binding name="noSecurity">
      <security mode="None"></security>
    </binding>
  </wsDualHttpBinding>
  <wsHttpBinding>
    <binding name="noSecurity">
      <security mode="None"></security>
    </binding>
  </wsHttpBinding>
</bindings>

Then I altered the endpoints to point to the appropriate binding. Here is the service configuration alteration.

<endpoint
    address="WsDualHttpBinding"
    bindingConfiguration="noSecurity"
    contract="WcfDemo.IDemoService"
    binding="wsDualHttpBinding"
    />
<endpoint
    address="WsHttpBinding"
    bindingConfiguration="noSecurity"
    contract="WcfDemo.IDemoService"
    binding="wsHttpBinding"
    />

here is the client configuration alteration.

<endpoint
    address="http://localhost:8081/WsDualHttpBinding"
    binding="wsDualHttpBinding"
    name="WSDualHttpBinding"
    bindingConfiguration="noSecurity"
    contract="IDemoService" />
<endpoint
    address="http://localhost:8081/WsHttpBinding"
    binding="wsHttpBinding"
    name="WSHttpBinding"
    bindingConfiguration="noSecurity"
    contract="IDemoService" />

The results for both WSDualHttpBinding and WSHttpBinding were much faster!

WSDualHttpBinding: Processed 5773 calls in 10 seconds
WSHttpBinding: Processed 17257 calls in 10 seconds
BasicHttpBinding: Processed 19528 calls in 10 seconds
NetTcpBinding: Processed 39756 calls in 10 seconds
NetNamedPipeBinding: Processed 47457 calls in 10 seconds

So as you can see you can get really different levels of performance based on the different binding you use. The ability to have these various endpoints provides a great mechanism for my services to reach all kinds of different clients with great interoperability and maximized speed for network and local communication. Best of all, it's all free...no extra coding! All I had to do to add the new binding was add the endpoint to the service configuration file. WCF takes care of all the rest for you...

Supplemental material - Sample Projects

WCF: A self-hosted service with multiple endpoints

Last night I started playing with more more interesting things in WCF (multiple endpoints) and I kept running into a wall: how do you set more than one http endpoint on the same service!? Nothing I was doing was working, then I ran into Indigo Girl's WCF book chapters online (see my next post). Her examples clearly explain what I was doing wrong. Let me explain how to do what I wanted to do in my own words...

Instead of having a different "server" for each endpoint of the same address scheme (i.e. http), you have a a base address for and then give each a name. There is one WSDL for all the endpoints of a service. That is: one service, one WSDL; not one endpoint, one WSDL. This stems from the fact that by default there are two endpoints repackages: mex and HTTP Get. The HTTP get one is the one that will help out with the WSDL.

Here is the fixed up code. By running this up and generating the proxy, we are able to have the complete mechanism for communication from the client to the service, including the configuration file (below).

Program.cs
Uri httpUri = new Uri("http://localhost:8081/");
using(ServiceHost hService = new ServiceHost(typeof(DemoService), httpUri)) {
 hService.AddServiceEndpoint(typeof(IDemoService), new BasicHttpBinding( ), "BasicService");
 hService.AddServiceEndpoint(typeof(IDemoService), new WSDualHttpBinding( ), "DualHttpService");

 hService.Open( );

 Console.WriteLine("Listening...");
 Console.ReadLine( );
}
client app.config

  <system.serviceModel>
    <client>
      <endpoint
        address="http://localhost:8081/BasicService"
        binding="basicHttpBinding"
        name="BasicHttpService"
        contract="IDemoService" />
      <endpoint
        address="http://localhost:8081/DualHttpService"
        binding="wsDualHttpBinding"
        name="DualHttpService"
        contract="IDemoService" />
    </client>
  </system.serviceModel>
Even when using entitely different protocols (the higher level http and say the lower level tcp), you have one WSDL. Of course in this case, since there are more one address scheme (http and net.tcp), you have more than one base address; one per scheme.
Program.cs
Uri netTcpAddress = new Uri("net.tcp://localhost:8080/");
Uri httpAddress = new Uri("http://localhost:8081/");
using (ServiceHost service = new ServiceHost(typeof(DemoService), new Uri[] { netTcpAddress, httpAddress })) {
 service.Open( );

 Console.WriteLine("Listening...");
 Console.ReadLine( );
}
server app.config

  <system.serviceModel>
    <services>
      <service type="WcfDemo.DemoService">
        <endpoint
          address="NetTcpService"
          contract="WcfDemo.IDemoService"
          binding="netTcpBinding"
          />
        <endpoint
          address="DualHttpService"
          contract="WcfDemo.IDemoService"
          binding="wsDualHttpBinding"
          />
      </service>
    </services>
  </system.serviceModel>
client app.config

  <system.serviceModel>
    <client>
      <endpoint
        address="net.tcp://localhost:8080/NetTcpService"
        binding="netTcpBinding"
        name="NetTcpService"
        contract="IDemoService" />
      <endpoint
        address="http://localhost:8081/DualHttpService"
        binding="wsDualHttpBinding"
        name="DualHttpService"
        contract="IDemoService" />
    </client>
  </system.serviceModel>

As you can see WCF really allows for some pretty powerful scenarios...

Video 4 (FWD) - "Using the Web Developer Toolbar"

One of the most powerful and appreciated extensions for Firefox is the Web Developer toolbar. This is the extension that helped convert me from an independent IEvangelist to a Firefox promoter and standards advocate. This tool puts the keys to client-side web development into the hands of the developer.

With a quick click of the mouse, the developer can now see all elements of a certain type, can disable or enable various portions of development ( i.e. JavaScript), or can view otherwise hidden form information. It's such a powerful tool that you'll never be able to do client-side web development again without it.

I do apologize for being so slow in the posting of these videos. There will be a few more in the future. These videos are from September 2005 and are for Firefox 1.0.x, but are still appropriate for Firefox 1.5.x (and Firefox 2.0)

"Common Language Runtime detected an invalid program"

If you've ever gotten this error you've probably been one of the most confused people in the world. In your debugging you may have seen that this message came from an InvalidProgramException.

Well, while this problem should be rare, here's an example harness of where you may see it.

// ThrowerHarness.cs
namespace ThrowerExample
{
  class ThrowerHarness
  {
    static void Main(string[] args)
    {
        try
        {
            Thrower.Start( );
        }
        catch (System.Exception ex)
        {
            System.Console.Write("Error: " + ex.Message);
        }
      }
    }
}

Alright, so where's it coming from?

In this case, it's actually coming from the IL.

// Thrower.il
.assembly ThrowerLib { }

.class public Thrower {
  .method static public void Start( ) {
    stloc.0
    throw
    ret
  }
}

This actually comes from invalid IL. In this case I'm putting 0 on the stack and then throwing...well, nothing really. This is not something a good compiler would create. If you see this it's probably a bug in the compiler or manually written IL.

Anyhow, to test the above do this...

ilasm /dll ThrowerLib.il
csc /r:ThrowerLib ThrowerHarness.cs