⛵ dotnet-sail

Downloads .NET project from Gist, GitHub, Git, or the web and runs it in a container. No CI or container registry required.

This container image performs Download (git clone or HTTP), Build (dotnet build), and Run (dotnet run) all at once, simply by specifying the source code address.

Important

dotnet-sail is primarily intended for temporary execution such as development, validation, and running sample code, and is not meant for use in production environments or the inner loop of day-to-day development.

Example: Run ASP.NET Core app from Gist

docker run --rm -it -p 8080:8080 mayuki/dotnet-sail https://gist.github.com/mayuki/6779e703c81333457aef4a3271d6d5c5

Example: Run Blazor sample app (dotnet/blazor-samples)

docker run --rm -it -p 8080:8080 mayuki/dotnet-sail -r publish https://github.com/dotnet/blazor-samples/tree/main/8.0/BlazorSample_BlazorWebApp

Note

To run a Blazor app, publish mode or DOTNET_URLS environment variable must be specified.

How to use

The container images are available from the following container registries:

• mayuki/dotnet-sail (Docker Hub)
• ghcr.io/mayuki/dotnet-sail (GitHub Packages Container Registry)

Run from Gist

docker run --rm -it mayuki/dotnet-sail https://gist.github.com/mayuki/d052d7457a63f25763ce8ecf04b1d0fc

If the Gist contains only one C# file, it automatically generates a C# project and starts it. If the Gist includes a .csproj file, it uses that to start the project.

Run from GitHub

docker run --rm -it -p 8080:8080 -e mayuki/dotnet-sail https://github.com/mayuki/dotnet-sail/tree/main/samples/SampleWebApp/SampleWebApp.csproj

Allowed URL forms

• https://github.com/<org>/<repo>
• https://github.com/<org>/<repo>/tree/<branch-or-hash>/<path-to-source-directory>
• https://github.com/<org>/<repo>/blob/<branch-or-hash>/<path-to-source-directory>/<target>.csproj

Run from Git

docker run --rm -it -p 8080:8080 mayuki/dotnet-sail https://github.com/mayuki/dotnet-sail.git?path=samples/SampleWebApp/SampleWebApp.csproj&branch=main

Options

• path: The path of the directory or file that includes projects and sources within the repository.
• branch: The branch to checkout when cloning the repository.

What does this do to help?

• Running temporary verification project
• Running samples or demonstration applications
• Hosting in environments where images can be easily run like Azure Container Instance, Container Apps, or Google Cloud Run

Typically, to run applications in container execution environments, you need to build for deployment, store build artifacts (container images), and set up secrets to make them deployable.

However, such settings are annoying when building a temporary environment for development, verification, or demonstration application. This container image realizes the developer's need to "I just want to run the source code that is here now."

What is this not intended for?

• Use in production environments
• Use as a day-to-day development environment

The container image is very large because it includes the .NET SDKs, and in addition, it requires time to fetch the source code and build it each time it starts up. This overhead becomes non-negligible for regular usage. For general development purposes, it is recommended to set up a CI/CD mechanism.

Also, at this point, there is no provided method for configuring authentication when fetching source code.

Command line options and environment variables

Environemnt variable	Command option	Description
DOTNET_SAIL_SOURCE	-s, --source	Gist, GitHub, or any other address that provides source code. (https://, git://...) Can be used instead of passing it as an argument.
DOTNET_SAIL_ARGUMENTS		The arguments to be passed to the application.
DOTNET_SAIL_VERBOSITY	-v, --verbosity	Set the verbosity level. The default is 'Information'. Allowed values are None, Error, Information and Trace.
DOTNET_SAIL_RUNNER	-r, --runner	The strategy to run for. The default is 'DotNetRunRunner'. Available runners are: DotNetRunRunner, run: Use 'dotnet build' and 'dotnet run' DotNetPublishAndExecRunner, publish: Use 'dotnet publish' and 'dotnet exec'.
DOTNET_SAIL_CONFIGURATION	-c, --configuration	The configuration to run for.
DOTNET_SAIL_LAUNCH_PROFILE	--launch-profile	The name of the launch profile to use when launching the application. This option is available with 'dotnet run' (DotNetRunRunner).
DOTNET_SAIL_NO_LAUNCH_PROFILE	--no-launch-profile	Do not attempt to use launchSettings.json to configure the application. This option is available with 'dotnet run' (DotNetRunRunner).
DOTNET_SAIL_EXEC_NAME	--exec-name	The name of the entrypoint assembly. This option is available with 'dotnet publish' and 'dotnet exec' (DotNetPublishAndExecRunner).
DOTNET_SAIL_SDK	--sdk	The SDK to run for single C# source project. The default is 'Microsoft.NET.Sdk'.
DOTNET_SAIL_TARGET_FRAMEWORK	--target-framework	The target framework to run for single C# source project. The default is 'net8.0'.
DOTNET_SAIL_ENV_*	-e, --env	The environment variables for the application to be run.

docker run --rm -it mayuki/dotnet-sail -e DOTNET_ENVIRONMENT=Production -r publish https://example.com/repo.git arg1 arg2

It is also possible to pass settings through environment variables of the container.

docker run --rm -it -e DOTNET_SAIL_ENV_DOTNET_ENVIRONMENT=Production \
                    -e DOTNET_SAIL_SOURCE=https://example.com/repo.git \
                    -e DOTNET_SAIL_RUNNER=publish \
                    -e DOTNET_SAIL_ARGUMENTS="arg1 arg2" \
                    mayuki/dotnet-sail

Run in cloud services

Azure Container Instance

In ACI, containers can easily be launched by specifying the container image and setting environment variables. The screenshot below is an example of running a Blazor sample application.

• Image source: Other registry
• Image: mayuki/dotnet-sail
• Environment variables:
  • DOTNET_URLS: http://+:80
  • DOTNET_SAIL_SOURCE: https://github.com/dotnet/blazor-samples/tree/main/8.0/BlazorSample_BlazorWebApp
  • DOTNET_SAIL_RUNNER: publish

License

MIT License