🍱 Better image metadata plus welcome message

- Added documentation URL
- Added link to Github Sponsors

Author: mkarlesky

build/base/templates/Dockerfile.erb

@@ -26,14 +26,17 @@ ENV CONTAINER_PLATFORM=$TARGETPLATFORM
 # Docker image tag for internal container use, set via Docker build argument
 ENV MADSCIENCELAB_VERSION=$CONTAINER_VERSION
 
+# Docker Hub URL
+ENV DOCKERHUB_URL=https://hub.docker.com/r/$IMAGE_NAME
+
 ##
 ## Docker Image Best Practices
 ## https://docs.docker.com/develop/develop-images/instructions/
 ##
 
 ## Metadata
 LABEL org.opencontainers.image.source=https://github.com/ThrowTheSwitch/MadScienceLabDocker/releases
-LABEL org.opencontainers.image.url=https://hub.docker.com/r/$IMAGE_NAME
+LABEL org.opencontainers.image.url=$DOCKERHUB_URL
 LABEL org.opencontainers.image.base.name=docker.io/bitnami/minideb
 LABEL org.opencontainers.image.title="Mad Science Lab"
 LABEL org.opencontainers.image.description="Contains Ceedling, supporting frameworks, and GNU C toolchain to provide a unit testing and build system environment for C projects"

build/base/templates/welcome.erb

@@ -5,8 +5,10 @@ echo "  This container includes:"
 <%# INSERT CONTENTS LIST -%>
 <% @contents.each {|item|%><%= "if [[ \"$CONTAINER_PLATFORM\" == #{item['platform']} ]]; then echo \"   * #{item['entry']}\"; fi\n"%><% } -%>
 echo "\e[0m"
+echo "  Documentation available at $DOCKERHUB_URL"
 echo "  NOTICE: Container user \`$(whoami)\` lacks root privileges as a security best practice."
-echo "  This limits installing software and more. See Docker Hub page for security docs and options."
+echo ""
+echo "  Please consider supporting this work: https://github.com/sponsors/ThrowTheSwitch"
 echo "\e[33m"
 echo "  To get started, enter \`ceedling help\` at the command line..."
 echo "\e[0m"