Docker image that creates, builds and runs a simple .net core console app using multi-stage build

Dockerfile

# A simple test using multi-stage builds in Docker to create a simple console app using dotnet core
# if only using the sdk, the image size is 1.7GB. Using multi-stage build the size is reduced to 180mb

FROM microsoft/dotnet:2.1-sdk AS build

## creates and builds the app 
RUN dotnet new console -lang "c#" -n testapp
RUN cd testapp
WORKDIR /testapp/
RUN dotnet build -c Release -o output

# uses output from build step and runs the dll
FROM microsoft/dotnet:2.1-runtime AS runtime
COPY --from=build /testapp/output .
ENTRYPOINT ["dotnet", "testapp.dll"]