Add ARM64 Docker image support (#3810)

* Add ARM64 Docker image support

* Fix

* Fix Docker build

* Fix typo

* Use OpenSSL 3 and PostgreSQL Lib v15 in Docker builder

* Use simple comments in Dockerfile

* Add comment explaining Docker image cross build

* Move docker step above tests for testing

* Move docker build step back to normal position

---------

Co-authored-by: Dessalines <dessalines@users.noreply.github.com>

.woodpecker.yml

@@ -239,7 +239,7 @@ steps:
     settings:
       repo: dessalines/lemmy
       dockerfile: docker/Dockerfile
-      platforms: linux/amd64
+      platforms: linux/amd64,linux/arm64
       build_args:
         - RUST_RELEASE_MODE=release
       auto_tag: true
@@ -252,7 +252,7 @@ steps:
     settings:
       repo: dessalines/lemmy
       dockerfile: docker/Dockerfile
-      platforms: linux/amd64
+      platforms: linux/amd64,linux/arm64
       build_args:
         - RUST_RELEASE_MODE=release
       tag: dev

docker/Dockerfile

@@ -1,45 +1,125 @@
-FROM clux/muslrust:1.70.0 as builder
-WORKDIR /app
-ARG CARGO_BUILD_TARGET=x86_64-unknown-linux-musl
+#
+# Docker multiarch image:
+#   We build the Lemmy binary for amd64 and arm64 in individual stages using the blackdex/rust-musl image (github.com/blackdex/rust-musl). 
+#   This image uses musl-cross-make (github.com/richfelker/musl-cross-make) to build a musl cross compilation toolchain for the target 
+#   architecture. It also includes pre-built static libraries such as libpq. These libraries can improve the compile time and eliminate 
+#   the requirement for extra dependencies in the final image.
+#
+#   During each build stage, we use the blackdex/rust-musl openssl 3 images and configure PQ_LIB_DIR=/usr/local/musl/pq15/lib to use 
+#   libpq v15. We also ensure the installation of the Rust toolchain corresponding to the target architecture using:
+#   `rustup target add $TARGET-unknown-linux-musl`.
+#
 
-# comma-seperated list of features to enable
+ARG RUST_VERSION=1.71.0
+ARG ALPINE_VERSION=3.18
 ARG CARGO_BUILD_FEATURES=default
+ARG RUST_RELEASE_MODE=debug
+ARG UID=911
+ARG GID=911
 
-# This can be set to release using --build-arg
-ARG RUST_RELEASE_MODE="debug"
+# AMD64 builder base
+FROM --platform=${BUILDPLATFORM} blackdex/rust-musl:x86_64-musl-stable-${RUST_VERSION}-openssl3 AS base-amd64
 
-COPY . .
+ENV DEBIAN_FRONTEND=noninteractive
+ENV CARGO_HOME=/root/.cargo
+ENV PQ_LIB_DIR=/usr/local/musl/pq15/lib
 
-# Build the project
-
-# Debug mode build
-RUN --mount=type=cache,target=/app/target \
-    if [ "$RUST_RELEASE_MODE" = "debug" ] ; then \
-      echo "pub const VERSION: &str = \"$(git describe --tag)\";" > "crates/utils/src/version.rs" \
-      && cargo build --target ${CARGO_BUILD_TARGET} --features ${CARGO_BUILD_FEATURES} \
-      && cp ./target/$CARGO_BUILD_TARGET/$RUST_RELEASE_MODE/lemmy_server /app/lemmy_server; \
+RUN apt update && apt install -y \
+    --no-install-recommends \
+    git
+
+RUN mkdir -pv "${CARGO_HOME}" && \
+    rustup set profile minimal && \
+    rustup target add x86_64-unknown-linux-musl
+
+# ARM64 builder base
+FROM --platform=${BUILDPLATFORM} blackdex/rust-musl:aarch64-musl-stable-${RUST_VERSION}-openssl3 AS base-arm64
+
+ENV DEBIAN_FRONTEND=noninteractive
+ENV CARGO_HOME=/root/.cargo
+ENV PQ_LIB_DIR=/usr/local/musl/pq15/lib
+
+RUN apt update && apt install -y \
+    --no-install-recommends \
+    git
+
+RUN mkdir -pv "${CARGO_HOME}" && \
+    rustup set profile minimal && \
+    rustup target add aarch64-unknown-linux-musl
+
+# AMD64 builder
+FROM base-amd64 AS build-amd64
+
+ARG CARGO_BUILD_FEATURES
+ARG RUST_RELEASE_MODE
+
+WORKDIR /lemmy
+
+COPY . ./
+
+# Debug build
+RUN --mount=type=cache,target=/lemmy/target set -ex; \
+    if [ "${RUST_RELEASE_MODE}" = "debug" ]; then \
+        echo "pub const VERSION: &str = \"$(git describe --tag)\";" > crates/utils/src/version.rs; \
+        cargo build --target=x86_64-unknown-linux-musl --features "${CARGO_BUILD_FEATURES}"; \
+        mv target/x86_64-unknown-linux-musl/debug/lemmy_server ./lemmy; \
     fi
 
-# Release mode build
-RUN \
-    if [ "$RUST_RELEASE_MODE" = "release" ] ; then \
-      echo "pub const VERSION: &str = \"$(git describe --tag)\";" > "crates/utils/src/version.rs" \
-      && cargo build --target ${CARGO_BUILD_TARGET} --features ${CARGO_BUILD_FEATURES} --release \
-      && cp ./target/$CARGO_BUILD_TARGET/$RUST_RELEASE_MODE/lemmy_server /app/lemmy_server; \
+# Release build
+RUN set -ex; \
+    if [ "${RUST_RELEASE_MODE}" = "release" ]; then \
+        echo "pub const VERSION: &str = \"$(git describe --tag)\";" > crates/utils/src/version.rs; \
+        cargo build --target=x86_64-unknown-linux-musl --features "${CARGO_BUILD_FEATURES}" --release; \
+        mv target/x86_64-unknown-linux-musl/release/lemmy_server ./lemmy; \
     fi
 
-# The alpine runner
-FROM alpine:3 as lemmy
+# ARM64 builder
+FROM base-arm64 AS build-arm64
+
+ARG CARGO_BUILD_FEATURES
+ARG RUST_RELEASE_MODE
 
-# Install libpq for postgres
-RUN apk add --no-cache libpq
+WORKDIR /lemmy
 
-# Copy resources
-COPY --from=builder /app/lemmy_server /app/lemmy
+COPY . ./
+
+# Debug build
+RUN --mount=type=cache,target=/lemmy/target set -ex; \
+    if [ "${RUST_RELEASE_MODE}" = "debug" ]; then \
+        echo "pub const VERSION: &str = \"$(git describe --tag)\";" > crates/utils/src/version.rs; \
+        cargo build --target=aarch64-unknown-linux-musl --features "${CARGO_BUILD_FEATURES}"; \
+        mv target/aarch64-unknown-linux-musl/debug/lemmy_server ./lemmy; \
+    fi
+
+# Release build
+RUN set -ex; \
+    if [ "${RUST_RELEASE_MODE}" = "release" ]; then \
+        echo "pub const VERSION: &str = \"$(git describe --tag)\";" > crates/utils/src/version.rs; \
+        cargo build --target=aarch64-unknown-linux-musl --features "${CARGO_BUILD_FEATURES}" --release; \
+        mv target/aarch64-unknown-linux-musl/release/lemmy_server ./lemmy; \
+    fi
+
+# Get target binary
+FROM build-${TARGETARCH} AS build
+
+## Final image
+FROM alpine:${ALPINE_VERSION} 
+
+ARG UID
+ARG GID
+
+RUN apk add --no-cache \
+    ca-certificates
+
+COPY --from=build --chmod=0755 /lemmy/lemmy /usr/local/bin
+
+RUN addgroup -S -g ${GID} lemmy && \
+    adduser -S -H -D -G lemmy -u ${UID} -g "" -s /sbin/nologin lemmy
 
-# Create non-privileged user
-RUN adduser -h /app -s sh -S -u 1000 lemmy
-RUN chown -R lemmy /app
 USER lemmy
 
-CMD ["/app/lemmy"]
+CMD ["lemmy"]
+
+EXPOSE 8536
+
+STOPSIGNAL SIGTERM