Add timezone support (#550)

Dockerfile

@@ -13,9 +13,11 @@ RUN --mount=type=cache,target=/root/.cache/go-build \
 
 FROM alpine AS certs
 RUN apk add -U \
-    ca-certificates
+    ca-certificates \
+    tzdata
 
 FROM scratch
 ENTRYPOINT ["/mc-router"]
 COPY --from=certs /etc/ssl/certs/ /etc/ssl/certs
+COPY --from=certs /usr/share/zoneinfo /usr/share/zoneinfo
 COPY --from=builder /build/mc-router /mc-router

Dockerfile.release

@@ -1,11 +1,13 @@
 FROM alpine AS certs
 RUN apk add -U \
-    ca-certificates
+    ca-certificates \
+    tzdata
 
 FROM scratch
 
 ARG TARGETPLATFORM
 
 COPY --from=certs /etc/ssl/certs/ /etc/ssl/certs
+COPY --from=certs /usr/share/zoneinfo /usr/share/zoneinfo
 COPY $TARGETPLATFORM/mc-router /
 ENTRYPOINT ["/mc-router"]

README.md

@@ -121,6 +121,15 @@ Some other features included:
 
 The [multi-architecture image published at Docker Hub](https://hub.docker.com/repository/docker/itzg/mc-router) supports amd64, arm64, and arm32v6 (i.e. RaspberryPi).
 
+## Timezone
+
+The image bundles `tzdata` so log timestamps can match your local timezone. Pick one:
+
+- Set the `TZ` environment variable, e.g. `TZ=America/New_York`
+- Bind mount the host's zone file: `-v /etc/localtime:/etc/localtime:ro`
+
+If neither is set, timestamps are in UTC.
+
 ## Docker Compose Usage
 
 The diagram below shows how this `docker-compose.yml` configures two Minecraft server services named `vanilla` and `forge`, which also become the internal network aliases. _Notice those services don't need their ports exposed since the internal networking allows for the inter-container access._