Merge pull request #6 from PercussiveElbow/scratch_container

Scratch image base and drop root

Dockerfile

@@ -1,12 +1,15 @@
+# Build image to compile the app
 FROM crystallang/crystal:latest-alpine AS builder
-RUN apk --no-cache add ca-certificates
-RUN apk update && apk upgrade
+RUN apk update && apk upgrade && apk --no-cache add ca-certificates
 WORKDIR /app
-COPY . /app
+RUN adduser -S lowpriv
+COPY ./src /app/src/
 RUN crystal build --static --release /app/src/crobat_client.cr 
-FROM busybox:latest
-WORKDIR /app
+
+# Build the lightweight busybox based image
+FROM scratch
+COPY --from=builder /etc/passwd /etc/passwd
 COPY --from=builder  /app/crobat_client /app/crobat_client
-COPY --from=builder /etc/ssl/certs /etc/ssl/certs
-RUN ln -s /etc/ssl/certs/ca-certificates.crt /etc/ssl/cert.pem
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/cert.pem
+USER lowpriv
 ENTRYPOINT ["/app/crobat_client"]