We have support to build the image for branches and tags

Dockerfile

@@ -24,6 +24,14 @@ ENV DEBIAN_FRONTEND=noninteractive
 # Increase the value to force renstalling of all apt-get dependencies
 ENV FORCE_REINSTALL_APT_GET_DEPENDENCIES=1
 
+ARG AIRFLOW_TAG
+
+# If you build for different version it will invalidate the cache here and rebuild from scratch
+# This is typically used in release versions
+ENV AIRFLOW_TAG=${AIRFLOW_TAG:-"development"}
+
+RUN echo "Airflow tag: ${AIRFLOW_TAG}"
+
 # Install  build dependencies
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \

hooks/build

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+set +x
+
+# Pull the image for image currently built if it exists
+docker pull ${IMAGE_NAME} || true
+
+# Pull the image for latest build if it exists
+docker pull ${DOCKER_REPO}:latest || true
+
+if [[ ${CACHE_TAG} == "latest-clean" || ${CACHE_TAG} =~ "release.*" ]]; then
+    CACHE_SPEC="--no-cache"
+else
+    CACHE_SPEC="--cache-from ${IMAGE_NAME} --cache-from ${DOCKER_REPO}:latest"
+fi
+
+# Build the image using cached versions if present - both the branch/tag version and latest build can be used
+# as cache source - docker will choose appropriate cache based on hashes of the files changed
+docker build --pull --build-arg AIRFLOW_TAG=${CACHE_TAG} -f ${DOCKERFILE_PATH} -t ${IMAGE_NAME} \
+        ${CACHE_SPEC} .

setup.py

@@ -38,7 +38,7 @@
 try:
     with io.open('README.md', encoding='utf-8') as f:
         long_description = f.read()
-except FileNotFoundError as e:
+except FileNotFoundError:
     long_description = ''