Dotnet/C# goodness

Just a quick heads up to let people know I am actually doing something. I got a bit of inspiration from someone asking about interfacing from dotnet and thought: Well, why the heck not... 

? NSClient++ 0,4,0,140 2012-02-22 x64 booting...
...
d Loading plugin: DotnetPlugin
d Using factory: NSCP.Plugin.PluginFactory for test.dll
d About to load dotnet plugin: D:/source/nscp/build/x64//modules/dotnet\test.dll
d Plugin loaded: test.dll
e Hello World from C#
...
? Enter command to inject or exit to terminate...

check_dotnet
d Injecting: check_dotnet...
e Got command: check_dotnet/check_dotnet
d Result check_dotnet: WARNING
? WARNING:Hello from C#

This is the first working version of the new dot.net API and plugin support. This works via a proxy plugin (DotnetPlugins) which loads all configured dotnet plugins. Plugins can be written in pretty much any language and I am implementing mine in C#. It currently requires native protocol buffer support which is avalible for atleast C# and presumably others as well.

The API is a bit sketchy but follows closely how the internal API looks as well as the modern plugins for Lua and

Python.

The idea is that you have a factor class which creates instances of plugins like so: 

namespace NSCP.Plugin {
    public class PluginFactory : NSCP.IPluginFactory
    {
        public NSCP.IPlugin create(NSCP.ICore core, String alias)
        {
            return new test.MyPlugin(core);
        }
    }
}

Then the plugin itself has access to all internal functions such as settings and query and registry such so registering the commands looks like this: 

        public bool load(int mode)
        {
            core.getLogger().error("Hello World from C#");
            core.getRegistry().registerCommand("check_dotnet", "This is a sample command written in C#");
            return true;
        }

Then we can of course act on our command by providing a query handler like so: 

        public NSCP.IQueryHandler getQueryHandler()
        {
            return new MyQueryHandler(core);
        }

The last and rather messy step (mainly due top the extreme verbosity of the ​C-Sharp port of protobuffer) is to provide the command handler. I hope at some point someone will be able to provide a plugin layer (written in native dot-net) to make is slightly less verbose much like I have for Python, C++ and Lua. 

        public NSCP.Result onQuery(string command, byte[] request)
        {
            NSCP.Result result = new NSCP.Result();

            // Process the incoming message
            Plugin.QueryRequestMessage request_message = Plugin.QueryRequestMessage.CreateBuilder().MergeFrom(request).Build();
            string intcommand = request_message.GetPayload(0).Command;
            core.getLogger().error("Got command: " + intcommand + "/" + command);

            // Create response message
            Plugin.Common.Types.Header.Builder header = Plugin.Common.Types.Header.CreateBuilder();
            header.SetVersion(Plugin.Common.Types.Version.VERSION_1);

            Plugin.QueryResponseMessage.Builder response_message = Plugin.QueryResponseMessage.CreateBuilder();
            Plugin.QueryResponseMessage.Types.Response.Builder response = Plugin.QueryResponseMessage.Types.Response.CreateBuilder();
            response.SetCommand(command);
            response.SetResult(Plugin.Common.Types.ResultCode.OK);
            response.SetMessage("Hello from C#");
            response_message.AddPayload(response.Build());
            response_message.SetHeader(header.Build());

            result.data = response_message.Build().ToByteArray();
            result.result = 1;
            return result;
        }

This will all be checked in (if you prefer to check the entire C# plugin) during the weekend and a new RC next week will feature this. As this has taken some time I will most likely have to skip a few of the bugs I was planing to fix :) So hopefully the next RC will be the last one. Also note that the C# plugin API is sketchy so please use it but beware that things are bound to change as I discover issues and problems...

Michael Medin

Michael Medin

Comments

1. dglynn -- 2013-04-22 20:52

Hi Mike, what assembly might I pull into the example solution to get your example code to work? I noticed that the current release dll (DotNetPlugins?.dll) doesn't contain the interfaces that you are using above? I assume this is because it's still in devel?

R/Greg

2. mickem -- 2013-04-23 11:05

There is amissing DDL (called NSCPDOTNET.DLL) which is required currently you need to build that manually but this will be fixed in next nightly build... I have just forgotten...

Michael Medin

3. dglynn -- 2013-04-23 15:38

Mike, thanks!

4. dglynn -- 2013-04-24 20:16

Mike, loaded the test.dll module against nscp.exe 0.4.1.95 build and I'm getting 'Could not load NSLoadModuleEx'.

5. mickem -- 2013-04-24 20:25

Well, the way dot-net works is you need a proxy which is what the DotNetplugins? module is all about.

So what you do is: 

[/modules]
DotnetPlugins = enabled
[/modules/dotnet]
foo=my-dot-net-module.dll
bar=another-dot-net-module.dll
6. dglynn -- 2013-04-24 21:45

Ahhh, thanks for your help Mike. Sorry to bug you on this I'm just finding the configuration and loading of the modules a bit confusing. I'm now getting that there is a incorrect configuration exception while trying to addPlugin DotnetPlugins.dll? This is happening with me using the stable and release versions of nscp.exe

7. mickem -- 2013-04-25 05:57

First off the dotnet plugins are a bit experimental so there are some snags.

I will try to write up a guide for how to do it on my machine.

Michael Medin

8. dglynn -- 2013-04-25 19:25

Thanks again Mike, I'm just trying to convert all my external wrapped nsclient dotnet plugins to the new module format. It looks like this example code would be the best?:

using System; using System.Collections.Generic; using System.Text; using System.Runtime.InteropServices?;

namespace CsharpSamplePlugin? {

public class SamplePlugin? {

public class version {

public version(int major, int minor, int revision) {

this.major = major; this.minor = minor; this.revision = revision;

} public int major; public int minor; public int revision;

} public bool loadModule() {

return true;

} public bool unloadModule() {

return true;

} public string getModuleName() {

return "Sample C# Module";

} public string getModuleDescription() {

return "Sample C# Module";

}

public version getModuleVersion() {

return new version(0, 0, 1 );

}

public bool hasCommandHandler() {

return true;

} public bool hasMessageHandler() {

return false;

}

public int handleCommand(String command, List<String> args, ref String message, ref String perf) { if (command == "check_net") {

message = "Everything is not going to be ok!"; perf = "performance data is cool"; return 1;

} return -1; }

}

}