Setting up Rosbridge in a docker container

Introduction

This article shows the following:

how to get rosbridge working in a docker container
How to create a custom user in a dockerfile
how to set up rosbridge for use with a physical network, even one through a wifi NIC (which has historically been harder)

Folder structure

.
├── build
│   ├── Dockerfile
├── docker-compose.yaml

Dockerfile

FROM osrf/ros:humble-desktop
WORKDIR /temp
    
ENV RMW_IMPLEMENTATION=rmw_cyclonedds_cpp

RUN apt update && \ 
    apt install -y \ 
    iputils-ping \ 
    software-properties-common \
    ros-humble-rmw-cyclonedds-cpp \ 
    ros-dev-tools \
    ros-humble-rosbridge-server

ENV MYUSER=danaukes
ENV MYGROUP=danaukes
ENV MYUID=1000
ENV MYGID=1000

RUN apt install -y sudo && \ 
    addgroup --gid ${MYGID} ${MYUSER} && \
    adduser --gecos '' --disabled-password --uid ${MYUID} --gid ${MYGID} ${MYUSER} && \
    adduser ${MYUSER} sudo && \
    adduser ${MYUSER} adm && \
    echo "${MYUSER} ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers.d/nopasswd

USER ${MYUSER}

Docker Compose

version: '2'

services:
  ros2:
    build: ./build
    user: danaukes
    networks:
      network:
        ipv4_address: "192.168.4.8"
    dns:
      - 192.168.4.1
    ports:
      - "9090:9090"
    command: bash -c "source /opt/ros/humble/setup.bash && ros2 launch rosbridge_server rosbridge_websocket_launch.xml"

networks:
  network:
    driver: ipvlan
    driver_opts:
      parent: wlp1s0
      ipvlan-mode: l2
    ipam:
      driver: default
      config:
        - subnet: 192.168.4.0/24
          gateway: 192.168.4.1
          ip_range: 192.168.4.1/24

Notes and snippets

may need to run this to enable the kind of networking needed above:

sysctl -w net.ipv4.ip_forward=1
sudo iptables -P FORWARD ACCEPT
 
sudo service docker restart
docker system prune

apt update
apt install -y openssh-server iputils-ping
echo "PermitRootLogin yes" >> /etc/ssh/sshd_config
#apt install nano
#nano /etc/ssh/sshd_config
service ssh start
#sudo passwd root

sudo /etc/init.d/ssh reload

docker compose up --force-recreate --build ros -d
docker exec -it --user user1 d64dd7a05bb3 /bin/bash

echo "export PATH=/opt/ros/galactic/bin:\$PATH" >> ~/.bashrc

old docker compose stuff

services:
  ros2:
    build: ./build
    # container_name: ros2
    user: danaukes
    # hostname: ros2
    # domainname: test
    networks:
      network:
        ipv4_address: "192.168.4.8"
    dns:
      - 192.168.4.1
    ports:
      # - 22/tcp
      - "9090:9090"
    # command: bash -c "sudo service ssh start && sleep infinity"
    # command: bash -c "sleep infinity"
    command: bash -c "source /opt/ros/humble/setup.bash && ros2 launch rosbridge_server rosbridge_websocket_launch.xml"
    # restart: unless-stopped

Old dockerfile commands

# RUN echo "source /opt/ros/humble/setup.bash" >> /home/${MYUSER}/.bashrc

# RUN source /opt/ros/humble/setup.bash

# RUN apt update && \ 
    # apt install -y \ 
    # openssh-server \ 
    # git \ 
    # net-tools \


# ENV ROS_LOCALHOST_ONLY=0

# ENV LD_LIBRARY_PATH=/opt/ros/humble/opt/yaml_cpp_vendor/lib:/opt/ros/humble/opt/rviz_ogre_vendor/lib:/opt/ros/humble/lib/x86_64-linux-gnu:/opt/ros/humble/lib


# RUN addgroup --gid ${MYGID} ${MYGROUP} && \
#     useradd -p $(perl -e 'print crypt($ARGV[0], "password")' 'test') -u ${MYUID} -g ${MYGID} -G adm,sudo ${MYUSER} && \
#     mkdir /home/${MYUSER} && \
#     chown ${MYUSER}:${MYGROUP} /home/${MYUSER} && \
#     echo "${MYUSER} ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers.d/nopasswd

#COPY . .

#ENV MYVAR=hello
#ENV MYPW=test
#COPY requirements.txt requirements.txt
#RUN echo "PermitRootLogin yes" >> /etc/ssh/sshd_config && service ssh start
#RUN adduser ${user} && usermod -aG adm ${user} && usermod -aG sudo ${user}
#RUN cd code_git_tools && bash add_to_path.bash && bash add_to_pythonpath.bash 
#RUN eval `ssh-agent -s`
#EXPOSE 5000
#ADD /test/code_git_tools /test/code_git_tools/
#CMD ["gitman", "status"]

External Resources

Note: Another important thing to remember (Macvlan and IPvlan): Traffic to and from the master device cannot be sent to and from slave devices. If you need to enable master to slave communication see section “Communication with the host (default-ns)” in the “IPVLAN – The beginning” paper published by one of the IPvlan authors (Mahesh Bandewar). found here