ops: improve dockerfile

Author: nunom27

Dockerfile

@@ -71,7 +71,7 @@ RUN mix release
 FROM ${RUNNER_IMAGE} AS final
 
 RUN apt-get update \
-  && apt-get install -y --no-install-recommends libstdc++6 openssl libncurses6 locales ca-certificates \
+  && apt-get install -y --no-install-recommends libstdc++6 openssl libncurses6 locales ca-certificates curl \
   && rm -rf /var/lib/apt/lists/*
 
 # Set the locale
@@ -98,4 +98,9 @@ USER nobody
 # above and adding an entrypoint. See https://github.com/krallin/tini for details
 # ENTRYPOINT ["/tini", "--"]
 
-CMD ["/app/bin/server"]
+EXPOSE 4000
+
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s \
+  CMD curl -f http://localhost:4000/ || exit 1
+
+CMD ["sh", "-c", "/app/bin/migrate && /app/bin/server"]