TSST Network Project

Development setup

See Development setup and Contributing.

First stage

See First stage.

Launch it

Simply go to one of the directories: mpls for MPLS and Transport Plane (first stage) or eon for EON and Control Plane (second stage).

Then, using python3 launch start.py script. You will have to build the project first, so python3 start.py -b to build. If it fails the first time, give it a second try, it usually happens that way.

Then simply launch python3 start.py and the project will start.

You can kill all the processes with python3 start.py -k.

I recommend using PowerShell (or PS in Windows Terminal) when on Windows or Alacritty when everywhere else.

Our experience after finishing the project

Tools

Please DO NOT USE VS Code with the tools from Microsoft. They are a piece of garbage, as of early 2021. JetBrains' Rider was our IDE of choice. You can't go wrong with any of their products. Being cross-platform is a huge advantage.

Scripts

Especially for cross-platform development, choose some modern scripting language like Python or Ruby. I chose Python, because I was already familiar with it. There were no problems with it on Windows, Linux and MacOS, which was tested. Our startup scripts were a bit quick 'n' dirty, so maybe don't rely on them as they are, but from my experience Python gives you a bit more flexibility with variables, uniform path handling and so on over shell or batch scripts.

Code reuse

The code in eon/Common dotnet core project can be reused for future TSST projects. Most of the classes there are generic, the only thing you have to provide are some model classes (like RequestPacket for instance).

Such code reuse wouldn't be possible without Dependency Injection programming principle that is one of the SOLID principles of, well, solid Object Oriented Programming. Read more about it on Wikipedia – dependency injection and Wikipedia – SOLID.

Importing to your project

Simply download Common-0.1.0.zip from releases and put it in your project next to other components.

Put the following in the *.csproj file:

  <ItemGroup>
    <ProjectReference Include="..\Common\Common.csproj" />
  </ItemGroup>

Now you can use the Common library like it's local code. You can also see an example e.g. in eon/CableCloud/CableCloud.csproj file.

Data models

I recommend using MessagePack as a serializing library. Mainly because it's binary, which seemed to be a requirement, but it's also easy to implement and provides useful methods for (de)serialization.

If you use the code from the Common library, you have to write a model that implements ISerializablePacket interface. A good example on how to do it would be Common.Models.GenericDataPacket, or, without multiple levels of inheritance, Common.Models.ManagementPacket.

Notice the Builder design pattern. From our experience it did an amazing job at constructing different RequestPackets for different components. I strongly recommend it. For more details on this pattern, I recommend reading the Gang of Four's book on Design Patterns.

Networking

Our networking components, that are basically raw TCP ports and clients are sometimes a bit rough, but mostly stable.

Persistently connected ports: Used between nodes and CableCloud mainly. They let you send data in whichever direction you want, whenever you want. They don't normally disconnect, unless you shut down one of the nodes.
Examples: server: CableCloud.CableCloudManager._serverPort, client: ClientNode.ClientNodeManager._clientPort.

Request-response ports: Used between Control Plane components. They let you send a request and get a response. They immediately disconnect after that. You can, however receive a request, send from that method another request, making sort of a chain of requests and then the responses will trace back this chain. Consult any CP component, like NetworkCallController.NccState.OnCallRequestReceived() for example. It is worth noting, that this method, as well as many others were injected (DI principle) to the OneShotServerPort<> object.

For a full picture on how to use it, study the NetworkCallController component, as it is the simplest. Oh, and those components are async, so you need to "pause" the application while the ports are listening. That's why there's _idle.WaitOne(). It just pauses the main thread without putting a load on a CPU (an empty while (true) loop puts an enormous load, so don't do that).

I recommend wiring up your dependencies as high up in the execution hierarchy as possible (in our case in a Main() method, which is the highest). This way you can provide some mock implementations for testing, like MockConfigurationParser that you can find in any component.

Configuration

For your time's sake, please, PLEASE DO NOT USE XML. It's stupid, time-consuming and pointless. Use JSON and some library for deserialization. We thought it was a requirement to use XMLs, but nobody gave a damn, so you shouldn't too. Whatever you do, don't use xml.

Startup boilerplate

Your application has to start somehow, some things like loggers need to be initialized, so you need to write some boilerplate code. Offload it to a common library, like Common.Startup. This piece of code is a bit dirty, so don't use exactly that, but you get the idea.

Unit tests

Some bugs could be spotted upfront if we wrote some unit tests earlier for our util functions. You don't have to test everything, but generally, when you have a function that checks for the gateway port, it is a good idea to have it tested. At least it was our main bug factory. You can see an example in Common.test.Utils or RoutingController.test.

Additional libraries

We used and recommend NLog for logging, NUnit for unit testing and, of course, MessagePack for serialization.

Project organization

You can see our tools here on Github. We used built-in Issues, Projects and Pull requests, as well as Create Issue Branch plugin which I highly recommend.

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© 2020-2021 Blazej Sewera, Mateusz Winnicki, Andrzej Gawor