Contributor guide

Note: This document at present is for only code contributors. We should expand it so that it covers reporting bugs, filing issues, and writing docs.

Questions & online chat Discord

We have a Discord server to discuss Libplanet. There are some channels for purposes in the Libplanet category:

  • #libplanet-users: Chat with game programmers who use Libplanet. Ask questions to use Libplanet for your games. People here usually speak in Korean, but feel free to speak in English.
  • #libplanet-dev: Chat with maintainers and contributors of Libplanet. Ask questions to hack Libplanet and to make a patch for it. People here usually speak in Korean, but feel free to speak in English.

Prerequisites

You need .NET Core SDK 3.1+ which provides the latest C# compiler and .NET VM. Read and follow the instruction to install .NET Core SDK on the .NET Core downloads page. FYI if you use macOS and Homebrew you can install it by brew cask install dotnet-sdk command.

Make sure that your .NET Core SDK is 3.1 or higher. You could show the version you are using by dotnet --info command.

Although it is not necessary, you should install a proper IDE for .NET (or an OmniSharp extension for your favorite editor — except it takes hours to properly configure and integrate with your editor). C# is not like JavaScript or Python; it is painful to code in C# without IDE.

Unless you already have your favorite setup, we recommend you to use Visual Studio Code. It is free, open source, and made by Microsoft, which made .NET as well. So Visual Studio Code has a first-party C# extension which works well together.

Build

The following command installs dependencies (required library packages) and builds the entire Libplanet solution:

dotnet build

We use SonarAnalyzer to check our code quality but it takes longer to build. To skip the analyzer, you can use:

dotnet build -p:SkipSonar=true

Projects

The planetarium/libplanet repository on GitHub consists of several projects:

  • Libplanet: The main project, which contains the most of implementation code. It is distributed as a NuGet package with the same name: Libplanet.

  • Libplanet.Net: The peer-to-peer networking layer built on top of Libplanet. This is distributed as a distinct NuGet package: Libplanet.Net.

  • Libplanet.Stun: The project dedicated to implement TURN & STUN. This is distributed as a distinct NuGet package: Libplanet.Stun.

  • Libplanet.RocksDBStore: The IStore implementation built on RocksDB. As this depends on platform-dependent libraries (which is written in C/C++), this is distributed as a distinct NuGet package: Libplanet.RocksDBStore.

  • Libplanet.Analyzers: Roslyn Analyzer (i.e., lint) for game programmers who use Libplanet. This project is distributed as a distinct NuGet package: Libplanet.Analyzers.

  • Libplanet.Extensions.Cocona: The project to provide the Cocona commands to handle Libplanet structures in command line. This is distributed as a distinct NuGet package: Libplanet.Extensions.Cocona.

  • Libplanet.Tools: The CLI tools for Libplanet. This project is distributed as a distinct NuGet package: Libplanet.Tools. See its own README.md.

  • Libplanet.Explorer: Libplanet Explorer, a web server that exposes a Libplanet blockchain as a GraphQL endpoint. There is the official web front-end depending on this too: libplanet-explorer-frontend. Note that this project in itself is a library, and packaging it as an executable is done by a below project named Libplanet.Explorer.Executable.

  • Libplanet.Explorer.Executable: Turns Libplanet Explorer into a single executable binary so that it is easy to distribute.

  • Libplanet.Benchmarks: Performance benchmarks. See the Benchmarks section below.

  • Libplanet.Tests: Unit tests of the Libplanet project. See the Tests section below.

  • Libplanet.Net.Tests: Unit tests of the Libplanet.Net project.

  • Libplanet.Stun.Tests: Unit tests of the Libplanet.Stun project.

  • Libplanet.RocksDBStore.Tests: Unit tests of the Libplanet.RocksDBStore project.

  • Libplanet.Analyzers.Tests: Unit tests of the Libplanet.Analyzers project.

  • Libplanet.Explorer.Tests: Unit tests of the Libplanet.Explorer project.

  • Libplanet.Extensions.Cocona.Tests: Unit tests of the Libplanet.Extensions.Cocona project.

Tests Build Status (CircleCI) Codecov

We write as complete tests as possible to the corresponding implementation code. Going near to the code coverage 100% is one of our goals.

The Libplanet solution consists of several projects. Every project without .Tests suffix is an actual implementation. These are built to Libplanet*.dll assemblies and packed into one NuGet package.

Libplanet*.Tests is a test suite for the Libplanet*.dll assembly. All of them depend on Xunit, and every namespace and class in these corresponds to one in Libplanet* projects. If there's Libplanet.Foo.Bar class there also should be Libplanet.Foo.Bar.Tests to test it.

To build and run unit tests at a time with .NET Core execute the below command:

dotnet test

To run unit tests with .NET Framework on Windows:

nuget install xunit.runner.console -Version 2.4.1
msbuild /restore /p:TestsTargetFramework=net472
& (gci xunit.runner.console.*\tools\net472\xunit.console.exe | select -f 1) `
  (gci *.Tests\bin\Debug\net472\*.Tests.dll)

Or with Mono:

nuget install xunit.runner.console
msbuild /restore /p:TestsTargetFramework=net47
mono xunit.runner.console.*/tools/net47/xunit.console.exe \
    *.Tests/bin/Debug/net47/*.Tests.dll

TURN_SERVER_URLS

Some tests depend on a TURN server. If TURN_SERVER_URLS environment variable is present, these tests also run. Otherwise, these tests are skipped.

As the name implies, TURN_SERVER_URLS can have more than one TURN server URL. URLs are separated by whitespaces like turn://user:password@host:3478/ turn://user:password@host2:3478/. If multiple TURN servers are provided, each test case pick a random one to use so that loads are balanced.

FYI there are several TURN implementations like Coturn and gortc/turn, or cloud offers like Xirsys.

xunit-unity-runner

Unity is one of our platforms we primarily target to support, so we've been testing Libplanet on the actual Unity runtime, and you could see whether it's passed on CircleCI.

However, if it fails and it does not fail on other platforms but only Unity, you need to run Unity tests on your own machine so that you rapidily and repeatedly tinker things, make a try, and immediately get feedback from them.

Here's how to run Unity tests on your machine. We've made and used xunit-unity-runner to run Xunit tests on the actual Unity runtime, and our build jobs on CircleCI also use this. This test runner is actually a Unity app, though it's not a game app. As of June 2019, there are executable binaries for Linux, macOS, and Windows. Its usage is simple. It's a CLI app that takes absolute paths to .NET assemblies (.dll) that consist of test classes (based on Xunit).

You can build these assemblies using msbuild -r Mono or .NET Framework provide. You can't build them using dotnet build command or dotnet msbuild, because the Unity runtime is not based on .NET Core but Mono, which is compatible with .NET Framework 4.7. Please be sure that Mono's bin directory is prior to .NET Core's one (or it's okay too if .NET Core is not installed at all). Mono or .NET Framework's msbuild could try to use .NET Core's version of several utilities during build, and this could cause some errors.

The way to execute the runner binary depend on the platform. For details, please read xunit-unity-runner's README. FYI you can use -h/--help option as well.

To sum up, the instruction is like below (the example is assuming Linux):

msbuild -r -p:TestsTargetFramework=net47
xunit-unity-runner/StandaloneLinux64 \
  "$PWD"/*.Tests/bin/Debug/net47/*.Tests.dll

Style convention

Please follow the existing coding convention. We are already using several static analyzers. They are automatically executed together with msbuild, and will warn you if there are any style errors.

You should also register Git hooks we commonly use:

git config core.hooksPath hooks

We highly recommend you to install an extension for EditorConfig in your favorite editor. Some recent editors have built-in support for EditorConfig, e.g., Rider (IntelliJ IDEA), Visual Studio. Many editors have an extension to support EditorConfig, e.g., Atom, Emacs, Vim, VS Code.

Benchmarks

In order to track performance improvements or regressions, we maintain a set of benchmarks and continuously measure them in the CI. You can run benchmarks on your local environment too:

dotnet run -p Libplanet.Benchmarks -c Release -- -j short -f "*"

Note that there is -j short; without this a whole set of benchmarks takes quite a long time. This will print like below:

|               Method | UnrollFactor |      Mean |      Error |    StdDev |
|--------------------- |------------- |----------:|-----------:|----------:|
|       MineBlockEmpty |           16 |  12.20 ms |  11.649 ms | 0.6385 ms |
|  MineBlockOneTran... |            1 |  14.54 ms |   3.602 ms | 0.1974 ms |
|                  ... |          ... |       ... |        ... |       ... |

You can measure only part of benchmarks by -f/--filtering them:

dotnet run -p Libplanet.Benchmarks -c Release -- -j short -f "*MineBlock*"

All benchmark code is placed under Libplanet.Benchmarks project. As our benchmarks are based on BenchmarkDotNet, please read their official docs for details.

Releasing a new version

Read the Releasing guide which dedicates to this topic.