Fixed Dockerfile.

Author: sandeep-ps

sample-extractors/simple-extractor/Dockerfile

@@ -1,6 +1,6 @@
 FROM clowder/pyclowder:onbuild
 
-ENV EXTRACTION_FUNC=""
-ENV EXTRACTION_MODULE=""
+ENV EXTRACTION_FUNC=os.env.get('EXTRACTION_FUNC', '')
+ENV EXTRACTION_MODULE=os.env.get('EXTRACTION_MODULE', '')
 
-CMD python -c "from simple_extractor import SimpleExtractor; from EXTRACTION_MODULE import *; SimpleExtractor(${EXTRACTION_FUNC}).start()"
+CMD python -c "from simple_extractor import SimpleExtractor; from ${EXTRACTION_MODULE} import *; SimpleExtractor(${EXTRACTION_FUNC}).start()"