chore(Dockerfile): add local-dev-env build stage (PROJQUAY-2501) (#883)

When specified, the new build target (aka stage) builds quay the way
local-dev/Dockerfile used to, using local-dev/config.yml as
configuration, and starting up only the necessary tools for development.
See docker-compose.yml services:quay:build:target for how it's used.

Production builds should not be affected since the new target is not
referenced from anywhere but the docker-compose.yml.

Dockerfile

@@ -123,6 +123,26 @@ RUN curl -fsSL "https://github.com/quay/config-tool/archive/${CONFIGTOOL_VERSION
 COPY --from=config-editor /build/static/build  /go/src/config-tool/pkg/lib/editor/static/build
 RUN go install ./cmd/config-tool
 
+# Local dev only target. DO NOT USE FOR PROD!
+# It is similar to the `final` target, but uses development config.
+FROM base AS local-dev-env
+ENV QUAYCONF /quay-registry/local-dev
+
+RUN alternatives --set python /usr/bin/python3
+
+WORKDIR $QUAYDIR
+
+# Ordered from least changing to most changing.
+COPY --from=jwtproxy /usr/local/bin/jwtproxy /usr/local/bin/jwtproxy
+COPY --from=pushgateway /usr/local/bin/pushgateway /usr/local/bin/pushgateway
+COPY --from=build-python /app /app
+COPY --from=build-static /build/static ${QUAYDIR}/static
+
+EXPOSE 8080 8443 7443 9091 55443
+
+ENTRYPOINT ["dumb-init", "--", "/quay-registry/quay-entrypoint.sh"]
+CMD ["registry"]
+
 # Final is the end container, where all the work from the other
 # containers are copied in.
 FROM base AS final

docker-compose.yaml

@@ -42,9 +42,9 @@ services:
 
   quay:
     container_name: quay-quay
-    build: 
+    build:
       context: .
-      dockerfile: ./local-dev/Dockerfile
+      target: local-dev-env
     image: quay-local:local
     volumes:
       - ".:/quay-registry"