Bump up version + release process + OCI labels

Dockerfile

@@ -1,14 +1,8 @@
-FROM node:12.8.0-slim
+FROM node:13.10.1-alpine3.11
 LABEL maintainer="[email protected]"
 
-ARG VERSION=2.2.1
+ARG VERSION=4.0.0
 ARG BUILD_DATE
-LABEL org.label-schema.build-date=${BUILD_DATE}
-LABEL org.label-schema.schema-version="1.0"
-LABEL org.label-schema.name="yanzinetworks/wscat"
-LABEL org.label-schema.description="WebSocket cat"
-LABEL org.label-schema.url="https://github.com/websockets/wscat"
-LABEL org.label-schema.docker.cmd="docker run --rm -it --net=host yanzinetworks/wscat"
 
 # Create user
 ENV USER=wscat
@@ -25,4 +19,16 @@ RUN addgroup --gid "$GID" "$USER" && \
 RUN npm install -g wscat@${VERSION}
 
 USER ${USER}
-ENTRYPOINT [ "wscat" ]
+ENTRYPOINT [ "wscat" ]
+
+# OCI Annotation: https://github.com/opencontainers/image-spec/blob/master/annotations.md
+LABEL org.opencontainers.image.title="wscat"
+LABEL org.opencontainers.image.description="WebSocket cat"
+LABEL org.opencontainers.image.authors="Emmanuel Frecon <[email protected]>"
+LABEL org.opencontainers.image.url="https://github.com/YanziNetworks/wscat"
+LABEL org.opencontainers.image.documentation="https://github.com/YanziNetworks/wscat/README.md"
+LABEL org.opencontainers.image.source="https://github.com/YanziNetworks/wscat"
+LABEL org.opencontainers.image.version="$VERSION"
+LABEL org.opencontainers.image.created="$BUILD_DATE"
+LABEL org.opencontainers.image.vendor="Yanzi Networks AB"
+LABEL org.opencontainers.image.licenses="MIT"

README.md

@@ -26,3 +26,21 @@ docker build -t yanzinetworks/wscat:2.2.0 --build-arg VERSION=2.2.0 .
 
 Internally, the image installs [wscat] using `npm`. It uses a separate user
 called `wscat` with ids: `7532:7532`.
+
+## Release Tempo
+
+The intention for this repository is to follow the [release] tempo for the
+official [wscat] project. The project will typically pick the latest stable
+[node] Alpine image at release time. Generated images are automatically
+[tagged][tags] with the same version number as the [wscat] [release] number.
+
+Missing a release? Open a [PR]!
+
+Releases will be done through creating (git) tags with the same value as the one
+in the `VERSION` build argument of the [Dockerfile]
+
+  [release]: https://github.com/websockets/wscat/releases/
+  [node]: https://hub.docker.com/_/node
+  [tags]: https://hub.docker.com/r/yanzinetworks/wscat/tags
+  [PR]: https://github.com/YanziNetworks/wscat/pulls
+  [Dockerfile]: ./Dockerfile