Dockerfile: fix style

- don't cache packages to lighten the image.

Author: MisterDA

Dockerfile

@@ -1,32 +1,41 @@
-FROM ocaml/opam:alpine-3.20-ocaml-5.2 as build
+FROM ocaml/opam:alpine-3.20-ocaml-5.2 AS build
 
 # Install system dependencies
-RUN sudo apk update && sudo apk add --update libev-dev openssl-dev gmp-dev oniguruma-dev inotify-tools curl-dev autoconf
+RUN apk -U upgrade --no-cache && apk add --no-cache \
+    autoconf \
+    curl-dev \
+    gmp-dev \
+    inotify-tools \
+    libev-dev \
+    oniguruma-dev \
+    openssl-dev
 
 # Branch freeze was opam-repo HEAD at the time of commit
-RUN cd opam-repository && git pull origin c45f5bab71d3589f41f9603daca5acad14df0ab0 && opam update
+RUN cd ~/opam-repository && git fetch -q origin master && git reset --hard c45f5bab71d3589f41f9603daca5acad14df0ab0 && opam update
 
 WORKDIR /home/opam
 
-# Install Opam dependencies
-ADD ocamlorg.opam ocamlorg.opam
+# Install opam dependencies
+COPY --chown=opam --link ocamlorg.opam .
 RUN opam install . --deps-only
 
 # Build project
-COPY --chown=opam:opam . .
+COPY --chown=opam . .
 RUN opam exec -- dune build @install --profile=release
 
 # Launch project in order to generate the package state cache
-RUN cd opam-repository && git checkout master && git pull origin master && opam update
-ENV OCAMLORG_REPO_PATH opam-repository
-ENV OCAMLORG_PKG_STATE_PATH package.state
+RUN cd ~/opam-repository && git checkout master && opam update
+ENV OCAMLORG_PKG_STATE_PATH=package.state \
+    OCAMLORG_REPO_PATH=opam-repository
 RUN touch package.state && ./init-cache package.state
 
-FROM alpine:3.20 as run
 
-RUN apk update && apk add --update libev gmp git
+FROM alpine:3.20
 
-RUN chmod -R 755 /var
+RUN apk -U upgrade --no-cache && apk add --no-cache \
+    git \
+    gmp \
+    libev
 
 COPY --from=build /home/opam/package.state /var/package.state
 COPY --from=build /home/opam/opam-repository /var/opam-repository
@@ -38,12 +47,12 @@ RUN git clone https://github.com/ocaml-web/html-compiler-manuals /manual
 
 RUN git config --global --add safe.directory /var/opam-repository
 
-ENV OCAMLORG_REPO_PATH /var/opam-repository/
-ENV OCAMLORG_MANUAL_PATH /manual
-ENV OCAMLORG_PKG_STATE_PATH /var/package.state
-ENV DREAM_VERBOSITY info
-ENV OCAMLORG_HTTP_PORT 8080
+ENV DREAM_VERBOSITY=info \
+    OCAMLORG_HTTP_PORT=8080 \
+    OCAMLORG_MANUAL_PATH=/manual \
+    OCAMLORG_PKG_STATE_PATH=/var/package.state \
+    OCAMLORG_REPO_PATH=/var/opam-repository/
 
 EXPOSE 8080
 
-ENTRYPOINT /bin/server
+ENTRYPOINT ["/bin/server"]