refactor: replace supervisord with s6

This change looks to drop the python dependency in the base image and replaces supervisord with [s6](https://github.com/just-containers/s6-overlay).

If we could get this branch pushed to the `s6` tag on Docker it will allow us to test this with the downstream containers.

I will update the README.md if it's decided that we will adopt s6 over supervisord.

Dockerfile

@@ -1,25 +1,28 @@
 FROM ubuntu:bionic
 MAINTAINER LanCache.Net Team <[email protected]>
+
 ARG DEBIAN_FRONTEND=noninteractive
-RUN \
-  apt-get -y update && apt-get -y upgrade && \
-  apt-get -y install python3-pip curl wget bzip2 locales tzdata && \
-  locale-gen en_GB.utf8 && \
-  update-locale LANG=en_GB.utf8
-RUN \
-  pip3 install supervisor && \
-  mkdir --mode 777 -p /var/log/supervisor
-RUN \
-  apt-get -y clean && \
-  rm -rf /var/lib/apt/lists/*
+ARG ARCH="amd64"
+ARG OVERLAY_VERSION="v2.2.0.3"
+
 ENV \
-  SUPERVISORD_EXIT_ON_FATAL=1 \
+  S6_BEHAVIOUR_IF_STAGE2_FAILS=2 \
   LC_ALL=en_GB.UTF-8 \
   LANG=en_GB.UTF-8 \
   LANGUAGE=en_GB.UTF-8 \
-  TZ=Europe/London \
-  SUPERVISORD_LOGLEVEL=WARN
+  TZ=Europe/London
+
 COPY overlay/ /
-RUN chmod -R 755 /init /hooks
-ENTRYPOINT ["/bin/bash", "-e", "/init/entrypoint"]
-CMD ["/init/supervisord"]
+
+RUN \
+  apt-get -y update && apt-get -y upgrade && \
+  apt-get -y install curl wget bzip2 locales tzdata && \
+  locale-gen en_GB.utf8 && \
+  update-locale LANG=en_GB.utf8 \
+  cd /tmp && \
+  curl -sSfL -o s6-overlay.tar.gz "https://github.com/just-containers/s6-overlay/releases/download/${OVERLAY_VERSION}/s6-overlay-${ARCH}.tar.gz" && \
+  tar xfz s6-overlay.tar.gz -C / && \
+  apt-get -y clean && \
+  rm -rf /tmp/* /var/lib/apt/lists/*
+
+ENTRYPOINT ["/init"]

goss.yaml

@@ -3,10 +3,8 @@ package:
     installed: true
   curl:
     installed: true
-  python3-pip:
-    installed: true
   wget:
     installed: true
 process:
-  supervisord:
+  s6-svscan:
     running: true

overlay/etc/cont-init.d/00-asciilogo

@@ -0,0 +1,12 @@
+#!/usr/bin/with-contenv bash
+
+cat <<EOF
+  _                  _____           _                       _    
+ | |                / ____|         | |                     | |   
+ | |     __ _ _ __ | |     __ _  ___| |__   ___   _ __   ___| |_  
+ | |    / _\` | '_ \| |    / _\` |/ __| '_ \ / _ \ | '_ \ / _ \ __| 
+ | |___| (_| | | | | |___| (_| | (__| | | |  __/_| | | |  __/ |_  
+ |______\__,_|_| |_|\_____\__,_|\___|_| |_|\___(_)_| |_|\___|\__| 
+
+
+EOF

run-tests.sh

@@ -1,9 +1,3 @@
 #!/bin/bash
 
-if [[ "$@" == *" -- "* ]]; then
-	SD_LOGLEVEL="-e SUPERVISORD_LOGLEVEL=INFO"
-else
-	SD_LOGLEVEL="-- -e SUPERVISORD_LOGLEVEL=INFO"
-fi
-
-curl -fsSL https://raw.githubusercontent.com/lancachenet/test-suite/master/dgoss-tests.sh | bash -s -- --imagename="lancachenet/ubuntu:goss-test" $@ $SD_LOGLEVEL
+curl -fsSL https://raw.githubusercontent.com/lancachenet/test-suite/master/dgoss-tests.sh | bash -s -- --imagename="lancachenet/ubuntu:goss-test" $@