feat: add ARM64 multi-platform Docker image support

- Add linux-arm64 binary download from radar repo
- Create Dockerfile.multiplatform for Debian-based multi-arch images
- Create Dockerfile.alpine.multiplatform for Alpine-based multi-arch images
- Use TARGETARCH to select correct binary (amd64 vs arm64)
- Build and push images for both linux/amd64 and linux/arm64
- Update release notes to document ARM64 support
- Tag latest/debian-latest images as multi-platform
- Enables native Docker support on Apple Silicon and ARM64 servers

Author: joshrotenberg

.github/workflows/release.yml

@@ -33,6 +33,7 @@ jobs:
           # Copy all binaries to root for consistent access
           cp ./binaries/radar-agent-linux/radar-agent-linux ./radar-agent-linux
           cp ./binaries/radar-agent-linux-musl/radar-agent-linux-musl ./radar-agent-linux-musl
+          cp ./binaries/radar-agent-linux-arm64/radar-agent-linux-arm64 ./radar-agent-linux-arm64
           cp ./binaries/radar-agent-darwin/radar-agent-darwin ./radar-agent-darwin
 
           # Make binaries executable
@@ -51,6 +52,7 @@ jobs:
           path: |
             radar-agent-linux
             radar-agent-linux-musl
+            radar-agent-linux-arm64
             radar-agent-darwin
           retention-days: 1
 
@@ -68,6 +70,9 @@ jobs:
           name: agent-binaries
           path: ./
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
@@ -98,33 +103,31 @@ jobs:
         run: |
           echo "tag_name=${{ github.event.client_payload.ref }}" >> $GITHUB_OUTPUT
 
-      - name: Build and push Debian image
+      - name: Build and push multi-platform Debian image
         uses: docker/build-push-action@v5
         with:
           context: .
-          file: ./docker/Dockerfile
-          build-args: |
-            BINARY=radar-agent-linux
+          file: ./docker/Dockerfile.multiplatform
           push: true
           tags: |
+            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ steps.tag.outputs.tag_name }}
+            ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
             ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:debian-${{ steps.tag.outputs.tag_name }}
             ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:debian-latest
           labels: ${{ steps.meta.outputs.labels }}
-          platforms: linux/amd64
+          platforms: linux/amd64,linux/arm64
 
-      - name: Build and push Alpine image
+      - name: Build and push multi-platform Alpine image
         uses: docker/build-push-action@v5
         with:
           context: .
-          file: ./docker/Dockerfile.alpine
-          build-args: |
-            BINARY=radar-agent-linux-musl
+          file: ./docker/Dockerfile.alpine.multiplatform
           push: true
           tags: |
             ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:alpine-${{ steps.tag.outputs.tag_name }}
             ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:alpine-latest
           labels: ${{ steps.meta.outputs.labels }}
-          platforms: linux/amd64
+          platforms: linux/amd64,linux/arm64
 
   release:
     name: Create Release
@@ -156,7 +159,7 @@ jobs:
         run: |
           # Create and explicitly sign the tag with -s flag
           git tag -s ${{ steps.tag.outputs.tag_name }} -m "Release ${{ steps.tag.outputs.tag_name }}" --force
-          
+
           # Push the signed tag to the repository
           git push origin ${{ steps.tag.outputs.tag_name }} --force
 
@@ -168,24 +171,30 @@ jobs:
           files: |
             radar-agent-linux
             radar-agent-linux-musl
+            radar-agent-linux-arm64
             radar-agent-darwin
           make_latest: true
           body: |
             ## Radar Agent Release ${{ steps.tag.outputs.tag_name }}
 
             ### Quick Install
 
-            **Linux (glibc):**
+            **Linux AMD64 (glibc):**
             ```bash
             curl -L "https://github.com/redis-field-engineering/radar-agent/releases/download/${{ steps.tag.outputs.tag_name }}/radar-agent-linux" -o radar-agent
             ```
 
-            **Linux (musl):**
+            **Linux AMD64 (musl):**
             ```bash
             curl -L "https://github.com/redis-field-engineering/radar-agent/releases/download/${{ steps.tag.outputs.tag_name }}/radar-agent-linux-musl" -o radar-agent
             ```
 
-            **macOS:**
+            **Linux ARM64:**
+            ```bash
+            curl -L "https://github.com/redis-field-engineering/radar-agent/releases/download/${{ steps.tag.outputs.tag_name }}/radar-agent-linux-arm64" -o radar-agent
+            ```
+
+            **macOS (Apple Silicon):**
             ```bash
             curl -L "https://github.com/redis-field-engineering/radar-agent/releases/download/${{ steps.tag.outputs.tag_name }}/radar-agent-darwin" -o radar-agent
             ```
@@ -196,13 +205,25 @@ jobs:
             sudo cp radar-agent /usr/local/bin/radar-agent
             ```
 
-            **Docker:**
+            **Docker (Multi-Platform - AMD64 & ARM64):**
             ```bash
-            # Alpine (recommended)
-            docker pull ghcr.io/redis-field-engineering/radar-agent:alpine-${{ steps.tag.outputs.tag_name }}
+            # Latest (Debian-based, works on both AMD64 and ARM64)
+            docker pull ghcr.io/redis-field-engineering/radar-agent:latest
+
+            # Specific version
+            docker pull ghcr.io/redis-field-engineering/radar-agent:${{ steps.tag.outputs.tag_name }}
 
+            # Alpine (recommended for minimal size)
+            docker pull ghcr.io/redis-field-engineering/radar-agent:alpine-latest
+            
             # Debian
-            docker pull ghcr.io/redis-field-engineering/radar-agent:debian-${{ steps.tag.outputs.tag_name }}
+            docker pull ghcr.io/redis-field-engineering/radar-agent:debian-latest
             ```
+
+            ### Platform Support
+
+            - **AMD64 (x86_64)**: All binaries and Docker images
+            - **ARM64 (aarch64)**: Native binary + multi-platform Docker images
+            - **Apple Silicon (M1/M2/M3)**: Native macOS binary + ARM64 Docker images
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

docker/Dockerfile.alpine.multiplatform

@@ -0,0 +1,51 @@
+FROM alpine:3.18
+
+# TARGETARCH is automatically set by Docker buildx (amd64, arm64, etc.)
+ARG TARGETARCH
+
+LABEL org.opencontainers.image.source="https://github.com/redis-field-engineering/radar-agent" \
+  org.opencontainers.image.licenses="Redis, Inc." \
+  org.opencontainers.image.authors="Radar Team"
+
+# Install required packages and create user
+RUN apk add --no-cache \
+    ca-certificates \
+    curl \
+    libgcc && \
+    adduser -D -g "" appuser
+
+# Create necessary directories
+RUN mkdir -p /certs /etc/agent /home/appuser/bin && \
+    chown -R appuser:appuser /certs /etc/agent /home/appuser
+
+# Copy default config (customers may override via volume)
+COPY --chown=appuser:appuser radar-agent-config-sample.yml /etc/agent/config.yaml
+
+# Copy the correct binary based on architecture
+# For Alpine, we use musl binaries
+# Note: Currently we only have musl for amd64, so arm64 will use glibc binary
+COPY radar-agent-linux* /tmp/
+RUN if [ "$TARGETARCH" = "amd64" ]; then \
+      cp /tmp/radar-agent-linux-musl /usr/local/bin/radar-agent || cp /tmp/radar-agent-linux /usr/local/bin/radar-agent; \
+    elif [ "$TARGETARCH" = "arm64" ]; then \
+      cp /tmp/radar-agent-linux-arm64 /usr/local/bin/radar-agent; \
+    fi && \
+    chmod +x /usr/local/bin/radar-agent && \
+    rm -rf /tmp/radar-agent-*
+
+USER appuser
+
+# Environment defaults
+ENV AGENT_CONFIG=/etc/agent/config.yaml \
+    AGENT_TLS_CERT=/certs/server.pem \
+    AGENT_TLS_KEY=/certs/server.key
+
+# Expose volumes for certs and config
+VOLUME ["/certs", "/etc/agent"]
+
+# Healthcheck for orchestrators
+HEALTHCHECK --interval=30s --timeout=5s \
+  CMD ["radar-agent", "--health"] || exit 1
+
+ENTRYPOINT ["radar-agent"]
+CMD ["--config", "/etc/agent/config.yaml"]

docker/Dockerfile.multiplatform

@@ -0,0 +1,59 @@
+FROM debian:bookworm-slim
+
+# TARGETARCH is automatically set by Docker buildx (amd64, arm64, etc.)
+ARG TARGETARCH
+
+LABEL org.opencontainers.image.source="https://github.com/redis-field-engineering/radar-agent" \
+  org.opencontainers.image.licenses="Redis, Inc." \
+  org.opencontainers.image.authors="Radar Team"
+
+# Install required packages
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+    libssl3 \
+    ca-certificates \
+    curl && \
+    rm -rf /var/lib/apt/lists/* && \
+    adduser --disabled-password --gecos "" appuser
+
+# Create necessary directories
+RUN mkdir -p /certs /etc/agent /home/appuser/bin && \
+    chown -R appuser:appuser /certs /etc/agent /home/appuser
+
+# Copy default config (customers may override via volume)
+COPY --chown=appuser:appuser radar-agent-config-sample.yml /etc/agent/config.yaml
+
+# Copy the correct binary based on architecture
+# For amd64: use radar-agent-linux
+# For arm64: use radar-agent-linux-arm64
+RUN if [ "$TARGETARCH" = "amd64" ]; then \
+      echo "Using AMD64 binary"; \
+    elif [ "$TARGETARCH" = "arm64" ]; then \
+      echo "Using ARM64 binary"; \
+    fi
+
+COPY radar-agent-linux* /tmp/
+RUN if [ "$TARGETARCH" = "amd64" ]; then \
+      cp /tmp/radar-agent-linux /usr/local/bin/radar-agent; \
+    elif [ "$TARGETARCH" = "arm64" ]; then \
+      cp /tmp/radar-agent-linux-arm64 /usr/local/bin/radar-agent; \
+    fi && \
+    chmod +x /usr/local/bin/radar-agent && \
+    rm -rf /tmp/radar-agent-*
+
+USER appuser
+
+# Environment defaults
+ENV AGENT_CONFIG=/etc/agent/config.yaml \
+    AGENT_TLS_CERT=/certs/server.pem \
+    AGENT_TLS_KEY=/certs/server.key
+
+# Expose volumes for certs and config
+VOLUME ["/certs", "/etc/agent"]
+
+# Healthcheck for orchestrators
+HEALTHCHECK --interval=30s --timeout=5s \
+  CMD ["radar-agent", "--health"] || exit 1
+
+ENTRYPOINT ["radar-agent"]
+CMD ["--config", "/etc/agent/config.yaml"]