fixed docker file creator

Author: maureeungaro

.github/workflows/build_and_test.yml

@@ -127,13 +127,13 @@ jobs:
           cache-from: type=registry,ref=${{ needs.discover.outputs.image }}:cache-amd64
           cache-to: type=registry,ref=${{ needs.discover.outputs.image }}:cache-amd64,mode=max
 
-      # NEW: export logs from the logs-export stage to local disk (no docker pull)
+      # export logs from the logs-export stage to local disk (no docker pull)
       - name: Export logs (amd64)
         uses: docker/build-push-action@v5
         with:
           context: .
           file: ./Dockerfile.generated
-          # Build only the tiny logs stage; reuse previous cache so it doesn't rebuild.
+          # Build only the tiny logs stage; reuse the previous cache so it doesn't rebuild.
           target: logs-export
           platforms: linux/amd64
           push: false

ci/dockerfile_creator.py

@@ -27,7 +27,7 @@ def available_images() -> str:
 
 
 def docker_header(image: str) -> str:
-	commands = f"FROM ghcr.io/gemc/g4install:{image}\n"
+	commands = f"FROM ghcr.io/gemc/g4install:{image} AS final\n"
 	commands += f"LABEL maintainer=\"Maurizio Ungaro <ungaro@jlab.org>\"\n\n"
 	commands += f"# run bash instead of sh\n"
 	commands += f"SHELL [\"/bin/bash\", \"-c\"]\n\n"
@@ -52,7 +52,7 @@ def install_gemc(tag: str) -> str:
 def log_exporters() -> str:
 	commands = '\n# logs exporter \n'
 	commands += 'FROM scratch AS logs-export \n'
-	commands += 'COPY --from=build /root/src/logs /logs \n'
+	commands += 'COPY --from=final /root/src/logs /logs \n'
 	return commands
 
 def create_dockerfile(image: str, tag: str) -> str: