Use a local script for pushing Docker images

Dockerfile

@@ -1,15 +1,14 @@
-FROM rust:alpine AS builder
+# This file is not intended to be used directly ;
+# please refer to the build script instead
 
-RUN apk add musl-dev perl make
+FROM debian:bullseye-slim
 
-WORKDIR /app
-
-COPY Cargo.toml Cargo.lock .
-COPY src src
-RUN cargo build --release
-
-FROM alpine
+# These two are provided by docker buildx
+ARG TARGETOS
+ARG TARGETARCH
+ARG TARGETVARIANT
 
 WORKDIR /app
-COPY --from=builder /app/target/release/tapo-rest .
+COPY target/building-for-docker/artifacts/${TARGETOS}/${TARGETARCH}/${TARGETVARIANT}/tapo-rest ./
+
 ENTRYPOINT ["./tapo-rest", "/app/devices.json", "--port=80"]

docker-build.rsh

@@ -0,0 +1,49 @@
+# Due to difficulties building cross-platform binaries with Docker,
+# I resort here to building locally using `cross` and then copying the
+# output into a container.
+
+# Ensure 'cross' is installed
+if whereis('cross') == null {
+    throw 'Please install "cross" to continue.'
+}
+
+# Ensure a container engine is installed
+if whereis('docker') == null && whereis('podman') == null {
+    throw 'Please install either "docker" or "podman" to continue.'
+}
+
+# Get name and version from the manifest
+let manifest = parseToml(readFile('Cargo.toml'))
+let { name, version } = $manifest['package']
+
+# List build targets
+let targets = map([
+    ['aarch64-unknown-linux-musl', 'linux/arm64'],
+    ['x86_64-unknown-linux-musl' , 'linux/amd64']
+])
+
+# Build for every image
+let buildDir = 'target/building-for-docker'
+
+for target, dockerPlatform in $targets {
+    echo "\nBuilding for target: $target...\n"
+
+    # We use a different target directory for each crate and each target, otherwise dependencies build
+    # may clash between platforms
+    let targetDir = "$buildDir/targets/$target"
+    mkdir -p -i $targetDir
+    cross build --release --target $target --target-dir $targetDir
+
+    # Put build artifact in the correct directory
+    let artifactsFile = "$buildDir/artifacts/$dockerPlatform/$name"
+    mkdir -p (parentDir($artifactsFile))
+    cp "$targetDir/$target/release/$name" $artifactsFile
+}
+
+# Build and publish Docker images
+echo '\nPublishing on Docker Hub...\n'
+
+docker buildx build --push . \
+    --platform ($targets.values().join(',')) \
+    --tag "clementnerma/$name:$version" \
+    --tag "clementnerma/$name:latest"