Docker files

[tsaoyu]

Docker is probably a good idea to create portable ROS image for us.

@ukcojamak9-martin create a general docker file that useful for our project. (Can you share docker and put some document in https://github.com/Maritime-Robotics-Student-Society/sailing-robot/wiki/Virtual-Machine-for-Windows-Mac-users ?)

And we want to know for Raspberry Pi, are there any restriction on hardware access?

Reference: http://blog.hypriot.com/

[majek9]

Guidance on installing Docker and a sailing-robot image are now in the wiki. dockerfile files have been pushed to the repository.

[takluyver]

Thanks @ukcojamak9-martin !

Leaving this open for now to discuss the tradeoffs of using docker on the raspi as well.

[tsaoyu]

Thanks Martin! I have tried docker on macOS. The isolated docker developing environment seems promising to me. And here are some bugs I found when I make it works on macOS.

1. Shared catkin workspace only works on Linux

   
   docker run --name sailing-robot -h sailing-robot -v /Users/caoyu/PycharmProjects/sailing-robot:/home/pi/sailing-robot --rm -it jamak9/sailing-robot:indigo

indigo: Pulling from jamak9/sailing-robot Digest: sha256:f3fe5cc108f20e9ec4f1224a09330fa9c0d2a53db60b23f90e2fa1c0bd6830dc Status: Downloaded newer image for jamak9/sailing-robot:indigo

And the error message: 

bash: /home/pi/sailing-robot/devel/_setup_util.py: /usr/local/bin/python: bad interpreter: No such file or directory Failed to run '"/home/pi/sailing-robot/devel/_setup_util.py" ': return code 126

This is because ROS was installed on mac with `homebrew` version of python. So the python interpreter is located at `/usr/local/bin/python`, cause error when linking host and container. 

I think it would be great if we can point out that "Shared folder allows easy access to source file but the compatibility is based on host environment. " For me I have completely give up running ROS on macOS due to regular crash of `rviz` and `rqt`. And I just wondering, does it possible to `git pull` in the container and keep it completed isolated with host? 

2. Terminal access to container works well

`docker exec -it sailing-robot bash` 

3. No lucky with `ssh` access and X-forwarding

After setup `sshd` in container, I have tried `ssh pi@172.17.0.2 ` but time out.

And also `ping 172.17.0.2` with result 

PING 172.17.0.2 (172.17.0.2): 56 data bytes Request timeout for icmp_seq 0 Request timeout for icmp_seq 1 Request timeout for icmp_seq 2 Request timeout for icmp_seq 3 Request timeout for icmp_seq 4 Request timeout for icmp_seq 5 Request timeout for icmp_seq 6

I am investigating this issue to make sure we can run GUI program like `rqt` and `rviz` with X-forwarding on host computer. It would be helpful if you can share the output on yours computer of the two commands I have tried.  

[majek9]

I am not sure what 2 commands you mean, I assume that you mean ssh and ping. ssh pi@172.17.0.2 gives me the password prompt, although if I hadn't ssh'd to it before I would have got:

The authenticity of host '172.17.0.2 (172.17.0.2)' can't be established. ECDSA key fingerprint is 2b:df:86:6e:e5:2a:24:4d:9b:81:87:d1:4f:66:de :02. Are you sure you want to continue connecting (yes/no)?` then the password prompt.

ping 172.17.0.2 gives me:

`PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data. 64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.147 ms 64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.122 ms 64 bytes from 172.17.0.2: icmp_seq=3 ttl=64 time=0.084 ms 64 bytes from 172.17.0.2: icmp_seq=4 ttl=64 time=0.124 ms 64 bytes from 172.17.0.2: icmp_seq=5 ttl=64 time=0.116 ms .....

Before trying number 1, see the next comment please.

1) If you remove -v /Users/caoyu/PycharmProjects/sailing-robot:/home/pi/sailing-robot from the docker run... command, then git clone, git pull and all other git commands should work as normal. However, everything that you do will be forgotten when you shutdown and restart the docker container.

You can also change it to this instead:: -v sailing-robot-git:/home/pi/sailing-robot

It will appear very similar to removing it totally, but it should remember the files within /home/pi/sailing-robot between restarts. (It does this by creating a local container to contain the files within that directory.)

I have just tested this on linux and once started I had to chown the /home/pi/sailing-robot to pi as it defaulted to root. It did remember the owner on restart though.

2) good. :-)

3) Assuming that the ssh server started properly, then my next step in diagnosing it would be to check the ip address, as the one in the script is the default one on my computer, it may be different on a mac though. Not sure how to do that on a mac, but on linux it is with ifconfig within the container. This comes up with two interfaces eth0 and lo it is labelled 'inet addr:' under the eth0 interface.

(Sorry if I am telling you stuff you already know, also if there is not enough detail please let me know.)

[majek9]

I am compiling a new docker image to hopefully fix bug for Mac's. I will update when it is compiled and uploaded.

[majek9]

I have now uploaded a new version of the docker image to hopefully fix the python location problem on mac's.

Please docker pull jamak9/sailing-robot and let me know if it has fixed it please.

[tsaoyu]

Thanks, Martin. I can confirm the symbol link for python interpreter works well!

[majek9]

How is SSH going, did you manage to check the ip address?

[tsaoyu]

I have managed to ssh into sailing-robot container with bit of effort Here I found it is not possible to ping into containers on macOS. As a work around I publish the ssh port 22 to 2222 with command

docker run -p 2222:22 -it jamak9/sailing-robot

then inside the container start ssh service.

And the ssh access is done by

ssh -p 2222 pi@localhost

I am still working on X window forwarding issue. But I am not really optimistic about the result, rviz doesn't play well with X window. To have a fully functional desktop development environment, I would suggest using native homebrew approach (for mac user on macOS).

[majek9]

Can you update the wiki with Mac instructions please, as you understand it much more than me. rviz works well for me on X windows, so maybe it is a mac issue?

I know nothing about homebrew, so can not advise on this.

[takluyver]

I've added the three scripts from the wiki into git, and made the one that starts the docker container a bit smarter to find the repository directory by itself.