Page 1 of 1 (2 posts)

  • talks about »
  • docker

Tags

Last update:
Sun Apr 30 05:45:14 2017

A Django site.

QGIS Planet

How to run a Linux GUI application on OSX using Docker

Ok so here is the scenario:

You just got a nice new MacBook 15″ Retina computer thinking it would work as nicely for Linux as your 13″ MacBook did and then you discover that the hybrid Intel/Nvidia card support in Linux is a show stopper and the WebCam does not work under Linux.

Well that is what happened to me, so I decided to give working with OSX a try on this laptop with the help of docker for running all those essential apps that I use for development. One thing I was curious about was whether it would be possible to run native GUI (X11) applications from inside docker and have them show up on my OSX desktop. I turns out that it is fairly easy to do this – here is what I did:

Overview

  • Install brew
  • Install socat
  • Install XQuartz
  • Install Docker (I used Kitematic beta)
  • Grab a docker image that has a gui app you want to run (I used my the QGIS Desktop image published by Kartoza on the docker hub)
  • Run it forwarding the display to your OSX host

 

Digging In

Ok first install brew (an apt-like package manager for OSX).

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Now install socat – a command line tool that lets you redirect sockets in unix like OS’s – thankfully it runs in OSX too as it is a really neat tool!

brew install socat

Next we are going to install XQuartz – which basically gives you an X11 display client on your OSX desktop. Just grab the package at http://xquartz.macosforge.org/landing/ and do the usual OSX procedure for installing it.

Unfortunately docker does not run natively on OSX, and the whole boot2docker setup is probably quite difficult to explain to people. However there is a very nice (currently beta) docker client being developed for OSX called kinematic. I installed kinematic and then simply hit shift-command-t in order to get a bash shell with docker available in it.

Now grab my QGIS desktop image for docker:

docker pull kartoza/qgis-desktop

Once the image is downloaded we are done with the basic setup and can kick over to running our Linux GUI application (obviously QGIS in this example).

Running QGIS

Ok so there are four steps we need to do to run our Linux app:

  1. Start socat (in my testing it had to be done first)
  2. Start XQuartz
  3. Start Kinematic
  4. Start QGIS

I started socat like this:

socat TCP-LISTEN:6000,reuseaddr,fork UNIX-CLIENT:\"$DISPLAY\"

It will run in the foreground waiting for connections and then pass them over to XQuartz.

Next I started XQuartz (you can close the XTerm window that opens by default).  In X11 preferences in XQuartz, in the security tab, check both boxes:

Screen Shot 2015-04-13 at 23.40.21

Next I started kinematic, and pressed SHIFT-COMMAND-T to open a docker terminal.

Screen Shot 2015-04-13 at 23.16.21

Lastly I ran the QGIS docker container like this:

docker run --rm -e DISPLAY=192.168.0.3:0 \
    -i -t -v /Users/timlinux:/home/timlinux \
    kartoza/qgis-desktop qgis

You can mix in any standard docker options there – in this case I created  shared volume between my OSX home directory and a /home/timlinux directory in the container. You need to determine the IP address of your OSX machine and use it instead of the IP address listed after DISPLAY in the above command. Here is a nice picture of QGIS (from a Linux container) running on my OSX desktop:

Screen Shot 2015-04-13 at 23.52.21

 

 

This same technique should work nicely with any other GUI application under Linux – I will mostly use if for running tests of QGIS based plugins and for using QGIS in my docker orchestrated environments.

Fun with docker and GRASS GIS software

GRASS GIS and dockerSometimes, we developers get reports via mailing list that this & that would not work on whatever operating system. Now what? Should we be so kind and install the operating system in question in order to reproduce the problem? Too much work… but nowadays it has become much easier to perform such tests without having the need to install a full virtual machine – thanks to docker.

Disclaimer: I don’t know much about docker yet, so take the code below with a grain of salt!

In my case I usually work on Fedora or Scientific Linux based systems. In order to quickly (i.e. roughly 10 min of automated installation on my slow laptop) try out issues of GRASS GIS 7 on e.g., Ubuntu, I can run all my tests in docker installed on my Fedora box:

# we need to run stuff as root user
su
# Fedora 21: install docker 
yum -y docker-io

# Fedora 22: install docker
dnf -y install docker

# enable service
systemctl start docker
systemctl enable docker

Now we have a running docker environment. Since we want to exchange data (e.g. GIS data) with the docker container later, we prepare a shared directory beforehand:

# we'll later map /home/neteler/data/docker_tmp to /tmp within the docker container
mkdir /home/neteler/data/docker_tmp

Now we can start to install a Ubuntu docker image (may be “any” image, here we use “Ubuntu trusty” in our example). We will share the X11 display in order to be able to use the GUI as well:

# enable X11 forwarding
xhost +local:docker

# search for available docker images
docker search trusty

# fetch docker image from internet, establish shared directory and display redirect
# and launch the container along with a shell
docker run -v /data/docker_tmp:/tmp:rw -v /tmp/.X11-unix:/tmp/.X11-unix \
       -e uid=$(id -u) -e gid=$(id -g) -e DISPLAY=unix$DISPLAY \
       --name grass70trusty -i -t corbinu/docker-trusty /bin/bash

In almost no time we reach the command line of this minimalistic Ubuntu container which will carry the name “grass70trusty” in our case (btw: read more about Working with Docker Images):

root@8e0f233c3d68:/# 
# now we register the Ubuntu-GIS repos and get GRASS GIS 7.0
add-apt-repository ppa:ubuntugis/ubuntugis-unstable
add-apt-repository ppa:grass/grass-stable
apt-get update
apt-get install grass7

This will take a while (the remaining 9 minutes or so of the overall 10 minutes).

Since I like cursor support on the command line, I launch (again?) the bash in the container session:

root@8e0f233c3d68:/# bash
# yes, we are in Ubuntu here
root@8e0f233c3d68:/# cat /etc/issue

Now we can start to use GRASS GIS 7, even with its graphical user interface from inside the docker container:

# create a directory for our data, it is mapped to /home/neteler/data/docker_tmp/
# on the host machine 
root@8e0f233c3d68:/# mkdir /tmp/grassdata
# create a new LatLong location from EPSG code
# (or copy a location into /home/neteler/data/docker_tmp/)
root@8e0f233c3d68:/# grass70 -c epsg:4326 ~/grassdata/latlong_wgs84
# generate some data to play with
root@8e0f233c3d68:/# v.random n=30 output=random30
# start the GUI manually (since we didn't start GRASS GIS right away with it before)
root@8e0f233c3d68:/# g.gui

Indeed, the GUI comes up as expected!

GRASS GIS 7 GUI in docker container

GRASS GIS 7 GUI in docker container

You may now perform all tests, bugfixes, whatever you like and leave the GRASS GIS session as usual.
To get out of the docker session:

root@8e0f233c3d68:/# exit    # leave the extra bash shell
root@8e0f233c3d68:/# exit    # leave docker session

# disable docker connections to the X server
[root@oboe neteler]# xhost -local:docker

To restart this session later again, you will call it with the name which we have earlier assigned:

[root@oboe neteler]# docker ps -a
# ... you should see "grass70trusty" in the output in the right column

# we are lazy and automate the start a bit
[root@oboe neteler]# GRASSDOCKER_ID=`docker ps -a | grep grass70trusty | cut -d' ' -f1`
[root@oboe neteler]# echo $GRASSDOCKER_ID 
[root@oboe neteler]# xhost +local:docker
[root@oboe neteler]# docker start -a -i $GRASSDOCKER_ID

### ... and so on as described above.

Enjoy.

The post Fun with docker and GRASS GIS software appeared first on GFOSS Blog | GRASS GIS Courses.

  • Page 1 of 1 ( 2 posts )
  • docker

Back to Top

Sponsors