example-voting-app/worker/Dockerfile

# because of dotnet, we always build on amd64, and target platforms in cli
# dotnet doesn't support QEMU for building or running. 
# (errors common in arm/v7 32bit) https://github.com/dotnet/dotnet-docker/issues/1537
# https://hub.docker.com/_/microsoft-dotnet
# hadolint ignore=DL3029
# to build for a different platform than your host, use --platform=<platform>
# for example, if you were on Intel (amd64) and wanted to build for ARM, you would use:
# docker buildx build --platform "linux/arm64/v8" .
FROM --platform=${BUILDPLATFORM} mcr.microsoft.com/dotnet/sdk:7.0 as build
ARG TARGETPLATFORM
ARG BUILDPLATFORM
RUN echo "I am running on $BUILDPLATFORM, building for $TARGETPLATFORM"

WORKDIR /source
COPY *.csproj .
RUN case ${TARGETPLATFORM} in \
         "linux/amd64")  ARCH=x64  ;; \
         "linux/arm64")  ARCH=arm64  ;; \
         "linux/arm64/v8")  ARCH=arm64  ;; \
         "linux/arm/v7") ARCH=arm  ;; \
    esac \
    && dotnet restore -r linux-${ARCH}

COPY . .
RUN  case ${TARGETPLATFORM} in \
         "linux/amd64")  ARCH=x64  ;; \
         "linux/arm64")  ARCH=arm64  ;; \
         "linux/arm64/v8")  ARCH=arm64  ;; \
         "linux/arm/v7") ARCH=arm  ;; \
    esac \
    && dotnet publish -c release -o /app -r linux-${ARCH} --self-contained false --no-restore

# app image
FROM mcr.microsoft.com/dotnet/runtime:7.0
WORKDIR /app
COPY --from=build /app .
ENTRYPOINT ["dotnet", "Worker.dll"]