Start a docker daemon in background

Dockerfile

@@ -1,9 +1,32 @@
+# This Dockerfile is used to run a self-hosted GitHub runner on Koyeb.
+
+# Unfortunately, docker:dind only exists for alpine, so we can't use it as a
+# base image. As a workaround, we first install system dependencies and copy the
+# binaries from docker:dind.
 FROM ubuntu
 
-ARG RUNNER_VERSION
-RUN test -n "$RUNNER_VERSION"
+RUN apt-get update
+
+RUN apt-get install -y \
+ btrfs-progs \
+ e2fsprogs \
+ iptables \
+ openssl \
+ xfsprogs \
+ xz-utils \
+ pigz \
+ fuse-overlayfs
+
+COPY --from=docker:dind /etc/subuid /etc/subuid
+COPY --from=docker:dind /etc/subgid /etc/subgid
 
-# Install various dependencies that might be useful in a runner
+COPY --from=docker:dind /usr/local/bin/ /usr/local/bin/
+COPY --from=docker:dind /usr/local/libexec/docker/cli-plugins/ /usr/local/libexec/docker/cli-plugins/
+
+# Then, we install various dependencies that might be useful in a runner.
+# This is minimalist and we might want to extend this list. See
+# https://github.com/actions/runner-images/tree/main to check what is installed
+# on GitHub runners by default.
 RUN apt-get update && apt-get install -y \
  libicu70 \
  ca-certificates \
@@ -18,19 +41,24 @@ RUN apt-get update && apt-get install -y \
  git \
  docker.io
 
-RUN pip install poetry
 
+# Finally, let's install the runner.
 RUN groupadd -r runner && useradd -r -g runner runner
 RUN mkdir -p /home/runner
 
 WORKDIR /home/runner
 RUN chown -R runner:runner /home/runner
 
+# In Oct. 2023, the last RUNNER_VERSION was 2.310.0.
+ARG RUNNER_VERSION
+RUN test -n "$RUNNER_VERSION"
+
 ADD https://github.com/actions/runner/releases/download/v${RUNNER_VERSION}/actions-runner-linux-x64-${RUNNER_VERSION}.tar.gz /home/runner/
 RUN tar xzf /home/runner/actions-runner-linux-x64-${RUNNER_VERSION}.tar.gz
 RUN rm -f /home/runner/actions-runner-linux-x64-${RUNNER_VERSION}.tar.gz
 
-USER runner
+#ENV RUNNER_ALLOW_RUNASROOT=1
 
 COPY ./entrypoint.sh /entrypoint.sh
-CMD ["/entrypoint.sh"]
+
+ENTRYPOINT ["/entrypoint.sh"]

entrypoint.sh

@@ -2,6 +2,19 @@
 
 set -e
 
+# Run docker daemon
+/usr/local/bin/dockerd-entrypoint.sh --tls=false >/dev/null 2>&1 &
+
+echo "Waiting for docker daemon to start..."
+while true;
+do
+ test -S /var/run/docker.sock && echo "ok!" && break
+ echo -n .
+ sleep .5
+done
+
+chown runner:runner /var/run/docker.sock
+
 for required_env in \
  REPO_URL \
  GITHUB_TOKEN \
@@ -40,14 +53,14 @@ then
  exit 1
 fi
 
-./config.sh \
- --url "$REPO_URL" \
- --token "$RUNNER_TOKEN" \
- --name "koyeb-runner-$(hostname)" \
+su -c "./config.sh \
+ --url '$REPO_URL' \
+ --token '$RUNNER_TOKEN' \
+ --name 'koyeb-runner-$(hostname)' \
  --runnergroup default \
  --no-default-labels \
- --labels "$RUNNER_LABELS" \
+ --labels '$RUNNER_LABELS' \
  --work workspace \
- --replace
+ --replace" runner
 
-exec ./run.sh
+exec su -c "/usr/local/bin/dockerd-entrypoint.sh ./run.sh" runner