PyDM Docker

A docker image with PyDM built-in.

How to run the container

Since PyDM uses a graphical interface, you need to pass additional arguments in order to properly forward X:

Linux:

$ docker pull pydm/pydm:latest
$ docker run --rm -ti \
-u $(id -u):$(id -g) \
-e DISPLAY=unix$DISPLAY \
-v "/tmp/.X11-unix:/tmp/.X11-unix" \
-v "/etc/group:/etc/group:ro" \
-v "/etc/passwd:/etc/passwd:ro" \
pydm/pydm

MacOS:

First install XQuartz. Then run it from the command line using open -a XQuartz. In the XQuartz preferences, go to the “Security” tab and make sure you’ve got “Allow connections from network clients” ticked. Restart XQuartz.

$ docker pull pydm/pydm:latest
$ IP=$(ifconfig en0 | grep inet | awk '$1=="inet" {print $2}')
$ xhost + $IP
$ docker run --rm -ti -e DISPLAY=$IP:0 pydm/pydm

Windows:

First, install an X server such as the one available in MobaXterm. Run Moba and ensure that the X server is running. Then:

C:\> docker pull pydm/pydm:latest
C:\> docker run --rm -ti -e DISPLAY=host.docker.internal:0.0 pydm/pydm

Sharing a folder with the container

In order to share a folder with your container you need to add an extra parameter to the way it is launched.

The extra parameter is in the following format: -v <local path>:<container path>. E.g.: To share a folder on linux /tmp/screens with the container and have it at /pydm/workspace you need to specify -v /tmp/screens:/pydm/workspace.

$ docker run --rm -ti -e DISPLAY=$IP:0 -v /tmp/screens:/pydm/workspace pydm/pydm

One recommendation is to use /pydm/workspace when sharing folders with this container. The container will use this folder as initial work directory.

For more information on shared folders please read the Docker documentation for volumes.

Changing default work directory

The default work directory is /pydm/workspace. In order to change that you need to specify an extra parameter at the launching script: --workdif <container path>

Launching PyDM and QtDesigner

Instead of getting access to the shell at the container you can specify a command to be executed such as pydm or designer.

E.g: Opening PyDM:

$ docker run --rm -ti -e DISPLAY=$IP:0 pydm/pydm pydm

The t option will allocate a pseudo-TTY, the i is for interactive and will keep STDIN open even if not attached.

In order to run detached remove -ti and use -d which will run the container in background and print the container ID.

Running with an user other than root

By default the container will run as root, which may cause some issues when a folder is shared with the container and files are modified. One suggestion valid for Linux and macOS to specify the UID and GID for the container is to use the -u parameter: -u $(id -u):$(id -g).

At a Linux system it is possible to share as ReadOnly the group and passwd files so the container will present the correct values for the username and group. For macOS I couldn't find a way to accomplish that yet.

Linux sharing group and passwd

$ docker pull pydm/pydm:latest
$ docker run \
--rm -ti \
-u $(id -u):$(id -g) \
-e DISPLAY=unix$DISPLAY \
-v "/tmp/.X11-unix:/tmp/.X11-unix" \
-v "/etc/group:/etc/group:ro" \
-v "/etc/passwd:/etc/passwd:ro" \
pydm/pydm

Useful aliases

Here are some useful aliases for Linux and macOS to launch QtDesigner and PyDM at the docker container sharing the current folder.

Linux

alias pydm='docker run --rm -d -u $(id -u):$(id -g) -e DISPLAY=unix$DISPLAY  -v ${PWD}:/pydm/workspace -v "/tmp/.X11-unix:/tmp/.X11-unix" -v "/etc/group:/etc/group:ro" -v "/etc/passwd:/etc/passwd:ro" pydm/pydm pydm'
alias designer='docker run --rm -d -u $(id -u):$(id -g) -e DISPLAY=unix$DISPLAY  -v ${PWD}:/pydm/workspace -v "/tmp/.X11-unix:/tmp/.X11-unix" -v "/etc/group:/etc/group:ro" -v "/etc/passwd:/etc/passwd:ro" pydm/pydm designer'
alias pydmbash='docker run --rm -it -u $(id -u):$(id -g) -e DISPLAY=unix$DISPLAY  -v ${PWD}:/pydm/workspace -v "/tmp/.X11-unix:/tmp/.X11-unix" -v "/etc/group:/etc/group:ro" -v "/etc/passwd:/etc/passwd:ro" pydm/pydm'
alias pydmipython='docker run --rm -it -u $(id -u):$(id -g) -e DISPLAY=unix$DISPLAY  -v ${PWD}:/pydm/workspace -v "/tmp/.X11-unix:/tmp/.X11-unix" -v "/etc/group:/etc/group:ro" -v "/etc/passwd:/etc/passwd:ro" pydm/pydm ipython'

macOS

Remember to also define IP and register it with xhost + ${IP} as instructed above.

alias pydm='docker run -d -u $(id -u):$(id -g) -e DISPLAY=${IP}:0 -v ${PWD}:/pydm/workspace pydm/pydm pydm'
alias designer='docker run --rm -d -u $(id -u):$(id -g) -e DISPLAY=${IP}:0 -v ${PWD}:/pydm/workspace pydm/pydm designer'
alias pydmbash='docker run --rm -it -u $(id -u):$(id -g) -e DISPLAY=${IP}:0 -v ${PWD}:/pydm/workspace pydm/pydm'
alias pydmipython='docker run --rm -it -u $(id -u):$(id -g) -e DISPLAY=${IP}:0 -v ${PWD}:/pydm/workspace pydm/pydm ipython'

How to build the container

You can build the container, for example, like this:

$ git clone https://github.com/hhslepicka/pydm-docker.git
$ cd pydm-docker
$ docker build -t pydm/pydm .