Mono

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Mono is an open source implementation of Microsoft’s .NET Framework

GitHub repo: https://github.com/mono/docker

Library reference

This content is imported from the official Docker Library docs, and is provided by the original uploader. You can view the Docker Store page for this repo at https://store.docker.com/images/mono.

Supported tags and respective Dockerfile links

For detailed information about the published artifacts of each of the above supported tags (image metadata, transfer size, etc), please see the repos/mono directory in the docker-library/repo-info GitHub repo.

For more information about this image and its history, please see the relevant manifest file (library/mono). This image is updated via pull requests to the docker-library/official-images GitHub repo.

What is Mono

Sponsored by Xamarin, Mono is an open source implementation of Microsoft’s .NET Framework based on the ECMA standards for C# and the Common Language Runtime. A growing family of solutions and an active and enthusiastic contributing community is helping position Mono to become the leading choice for development of cross platform applications.

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How to use this image

This image will run stand-alone Mono console apps.

Create a Dockerfile in your Mono app project

This example Dockerfile will run an executable called TestingConsoleApp.exe.

FROM mono:3.10-onbuild
CMD [ "mono",  "./TestingConsoleApp.exe" ]

Place this file in the root of your app, next to the .sln solution file. Modify the exectuable name to match what you want to run.

This image includes ONBUILD triggers that adds your app source code to /usr/src/app/source, restores NuGet packages and compiles the app, placing the output in /usr/src/app/build.

With the Dockerfile in place, you can build and run a Docker image with your app:

$ docker build -t my-app .
$ docker run my-app

You should see any output from your app now.

Credits

This Docker image is provided by Xamarin, for users of the Mono Project.

Thanks to Michael Friis for his preliminary work.

Image Variants

The mono images come in many flavors, each designed for a specific use case.

mono:<version>

This is the defacto image. If you are unsure about what your needs are, you probably want to use this one. It is designed to be used both as a throw away container (mount your source code and start the container to start your app), as well as the base to build other images off of.

mono:onbuild

This image makes building derivative images easier. For most use cases, creating a Dockerfile in the base of your project directory with the line FROM mono:onbuild will be enough to create a stand-alone image for your project.

While the onbuild variant is really useful for “getting off the ground running” (zero to Dockerized in a short period of time), it’s not recommended for long-term usage within a project due to the lack of control over when the ONBUILD triggers fire (see also docker/docker#5714, docker/docker#8240, docker/docker#11917).

Once you’ve got a handle on how your project functions within Docker, you’ll probably want to adjust your Dockerfile to inherit from a non-onbuild variant and copy the commands from the onbuild variant Dockerfile (moving the ONBUILD lines to the end and removing the ONBUILD keywords) into your own file so that you have tighter control over them and more transparency for yourself and others looking at your Dockerfile as to what it does. This also makes it easier to add additional requirements as time goes on (such as installing more packages before performing the previously-ONBUILD steps).

License

This Docker Image is licensed with the Expat License. See the Mono Project licensing FAQ for details on how Mono and associated libraries are licensed.

Supported Docker versions

This image is officially supported on Docker version 17.04.0-ce.

Support for older versions (down to 1.6) is provided on a best-effort basis.

Please see the Docker installation documentation for details on how to upgrade your Docker daemon.

User Feedback

Please report issues on the GitHub project.

library, sample, Mono