Improve Dockerfile

- Cross-compilation support (amd64 + arm64)
- Use cargo build cache
- Add opencontainers labels

.dockerignore

@@ -0,0 +1,4 @@
+scripts
+.github
+.editorconfig
+.pre-commit-hooks.yaml

Dockerfile

@@ -1,20 +1,45 @@
-FROM rust:alpine as base
+# syntax=docker/dockerfile:1
+FROM --platform=$BUILDPLATFORM tonistiigi/xx AS xx
 
-COPY . /src
+FROM --platform=$BUILDPLATFORM rust:1.74-alpine AS base
 
-RUN rustup update 1.74 && rustup default 1.74
-
-RUN apk update \
-    && apk add \
+RUN apk update && \
+    apk add \
         gcc \
-        g++
+        g++ \
+        clang
 
-RUN cd /src && cargo build --release
+COPY --from=xx / /
 
-FROM alpine as tool
+ARG TARGETPLATFORM
+RUN xx-info env
 
-COPY --from=base /src/target/release/oxipng /usr/local/bin
+RUN xx-apk add \
+    gcc \
+    musl-dev \
+    libdeflate
 
 WORKDIR /src
+
+COPY . .
+
+RUN --mount=type=cache,target=/root/.cargo/git/db \
+    --mount=type=cache,target=/root/.cargo/registry/cache \
+    --mount=type=cache,target=/root/.cargo/registry/index \
+    xx-cargo build --release && \
+    xx-verify /src/target/$(xx-cargo --print-target-triple)/release/oxipng && \
+    cp /src/target/$(xx-cargo --print-target-triple)/release/oxipng /src/target/oxipng
+
+FROM alpine AS tool
+
+LABEL org.opencontainers.image.title="Oxipng"
+LABEL org.opencontainers.image.description="Multithreaded PNG optimizer written in Rust"
+LABEL org.opencontainers.image.authors="Joshua Holmer <jholmer.in@gmail.com>"
+LABEL org.opencontainers.image.licenses="MIT"
+LABEL org.opencontainers.image.source="https://github.com/shssoichiro/oxipng"
+
+COPY --from=base /src/target/oxipng /usr/local/bin
+
+WORKDIR /work
 ENTRYPOINT [ "oxipng" ]
 CMD [ "--help" ]