port mac fix from #92

Author: pk910

Dockerfile-local

@@ -23,11 +23,12 @@ RUN apt-get update && apt-get -y upgrade && apt-get install -y --no-install-reco
   && update-ca-certificates
 ARG userid=10001
 ARG groupid=10001
-RUN groupadd -g ${groupid} assertoor && useradd -m -u ${userid} -g assertoor assertoor
+RUN (getent group ${groupid} || groupadd -g ${groupid} assertoor) && \
+    useradd -m -u ${userid} -g ${groupid} assertoor
 RUN echo "assertoor ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers.d/assertoor
 WORKDIR /app
 COPY --from=builder /src/bin/* /app/
-RUN chown -R assertoor:assertoor /app
+RUN chown -R assertoor:${groupid} /app
 RUN mkdir /workspace
 USER assertoor
 WORKDIR /workspace