To start a remote plug-in endpoint, use the PLUGIN_REMOTE_ENDPOINT_EXECUTABLE environment variable in the Dockerfile.

Procedure

  • Start a remote plug-in endpoint using the CMD command in the Dockerfile:

    Dockerfile example
    FROM fedora:30

RUN dnf update -y && dnf install -y nodejs htop && node -v

RUN mkdir /home/user

ENV HOME=/home/user

RUN mkdir /projects \
    && chmod -R g+rwX /projects \
    && chmod -R g+rwX "${HOME}"

CMD ${PLUGIN_REMOTE_ENDPOINT_EXECUTABLE}

  • Start a remote plug-in endpoint using the ENTRYPOINT command in the Dockerfile:

    Dockerfile example
    FROM fedora:30

RUN dnf update -y && dnf install -y nodejs htop && node -v

RUN mkdir /home/user

ENV HOME=/home/user

RUN mkdir /projects \
    && chmod -R g+rwX /projects \
    && chmod -R g+rwX "${HOME}"

ENTRYPOINT ${PLUGIN_REMOTE_ENDPOINT_EXECUTABLE}

Using a wrapper script

Some images use a wrapper script to configure permissions. The script is defined it in the ENTRYPOINT command of the Dockerfile to configure permissions inside the container, and it script executes a main process defined in the CMD command of the Dockerfile.

Eclipse Che uses such images with a wrapper script to provide permission configurations on different infrastructures with advanced security, for example on OpenShift.

  • Example of a wrapper script:

    #!/bin/sh

set -e

export USER_ID=$(id -u)
export GROUP_ID=$(id -g)

if ! whoami >/dev/null 2>&1; then
    echo "${USER_NAME:-user}:x:${USER_ID}:0:${USER_NAME:-user} user:${HOME}:/bin/sh" >> /etc/passwd
fi

# Grant access to projects volume in case of non root user with sudo rights
if [ "${USER_ID}" -ne 0 ] && command -v sudo >/dev/null 2>&1 && sudo -n true > /dev/null 2>&1; then
    sudo chown "${USER_ID}:${GROUP_ID}" /projects
fi

exec "$@"

  • Example of a Dockerfile with a wrapper script:

    Dockefile example
    FROM alpine:3.10.2

ENV HOME=/home/theia

RUN mkdir /projects ${HOME} && \
    # Change permissions to let any arbitrary user
    for f in "${HOME}" "/etc/passwd" "/projects"; do \
      echo "Changing permissions on ${f}" && chgrp -R 0 ${f} && \
      chmod -R g+rwX ${f}; \
    done

ADD entrypoint.sh /entrypoint.sh

ENTRYPOINT [ "/entrypoint.sh" ]
CMD ${PLUGIN_REMOTE_ENDPOINT_EXECUTABLE}

    In this example, the container launches the /entrypoint.sh script defined in the ENTRYPOINT command of the Dockerfile. The script configures the permissions and executes the command using exec $@. CMD is the argument for ENTRYPOINT, and the exec $@ command calls ${PLUGIN_REMOTE_ENDPOINT_EXECUTABLE}. A remote plug-in endpoint then starts in the container after permission configuration.