Multi-platform build (linux/amd64 and linux/arm64) (#230)

* wip

* pin to latest version, not commit

* test run

* Revert "test run"

This reverts commit 355e8f8.

Author: kokes

.github/workflows/publish.yml

@@ -24,6 +24,14 @@ jobs:
         with:
           persist-credentials: false
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@96fe6ef7f33517b61c61be40b68a1882f3264fb8 # v4.2.0
+        with:
+          platforms: linux/amd64,linux/arm64
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0
+
       - name: Log in to the Container registry
         uses: docker/login-action@dbcb813823bdd20940b903addbd779551569679f
         with:
@@ -41,6 +49,7 @@ jobs:
         uses: docker/build-push-action@53b7df96c91f9c12dcc8a07bcb9ccacbed38856a
         with:
           context: .
+          platforms: linux/amd64,linux/arm64
           push: true
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.26.5-alpine AS builder
+FROM --platform=$BUILDPLATFORM golang:1.26.5-alpine AS builder
 
 WORKDIR /src
 
@@ -12,8 +12,9 @@ RUN go mod download
 # Copy source code
 COPY . .
 
-# Build the binary
-RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-s -w" -o /proxy ./cmd/proxy
+# Build the binary for the target platform
+ARG TARGETARCH
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=${TARGETARCH} go build -ldflags="-s -w" -o /proxy ./cmd/proxy
 
 FROM alpine:3.24.1