Merge branch 'master' of github.com:heroku/heroku-buildpack-python

Readme.md

-# Heroku buildpack: Python
+# Heroku Buildpack: Python
 ![python-banner](https://cloud.githubusercontent.com/assets/51578/8914205/ecf2047c-346b-11e5-98c5-42547f9f4410.jpg)
 
 This is a [Heroku buildpack](http://devcenter.heroku.com/articles/buildpacks) for Python apps, powered by [pip](http://www.pip-installer.org/).
@@ -42,7 +42,7 @@ Specify a Runtime
 You can also provide arbitrary releases Python with a `runtime.txt` file.
 
     $ cat runtime.txt
-    python-3.5.0
+    python-3.5.1
 
 Runtime options include:
 

bin/compile

@@ -48,6 +48,8 @@ export PATH=$PATH:$ROOT_DIR/vendor/pip-pop
 
 # Sanitizing environment variables.
 unset GIT_DIR PYTHONHOME PYTHONPATH LD_LIBRARY_PATH LIBRARY_PATH
+unset RECEIVE_DATA SOURCE_VERSION RUN_KEY BUILD_INFO DEPLOY
+unset LOG_TOKEN DYNO CYTOKINE_LOG_FILE GEM_PATH
 
 bpwatch init $LOGPLEX_KEY
 bpwatch build python $BUILDPACK_VERSION $REQUEST_ID

bin/steps/collectstatic

 #!/usr/bin/env bash
 
+# Django Collectstatic runner. If you have Django installed, collectstatic will
+# automatically be executed as part of the build process. If collectstatic
+# fails, your build fails.
+
+# This functionality will only activate if Django is in requirements.txt.
+
+# Runtime arguments:
+#   - $DISABLE_COLLECTSTATIC: disables this functionality.
+#   - $DEBUG_COLLECTSTATIC: upon failure, print out environment variables.
+
 source $BIN_DIR/utils
 
+# Location of 'manage.py', if it exists.
 MANAGE_FILE=$(find . -maxdepth 3 -type f -name 'manage.py' -printf '%d\t%P\n' | sort -nk1 | cut -f2 | head -1)
 MANAGE_FILE=${MANAGE_FILE:-fakepath}
 
+# Legacy file-based support for $DISABLE_COLLECTSTATIC
 [ -f .heroku/collectstatic_disabled ] && DISABLE_COLLECTSTATIC=1
 
-bpwatch start collectstatic
+# Ensure that Django is explicitily specified in requirments.txt
+pip-grep -s requirements.txt django Django && DJANGO_INSTALLED=1
 
-if [ ! "$DISABLE_COLLECTSTATIC" ] && [ -f "$MANAGE_FILE" ]; then
-    set +e
+bpwatch start collectstatic  # metrics collection
 
-    echo "-----> Preparing static assets"
-    # Check if collectstatic is configured properly.
-    python $MANAGE_FILE collectstatic --dry-run --noinput &> /dev/null && RUN_COLLECTSTATIC=true
+if [ ! "$DISABLE_COLLECTSTATIC" ] && [ -f "$MANAGE_FILE" ] && [ "$DJANGO_INSTALLED" ]; then
+    set +e
 
-    # Compile assets if collectstatic appears to be kosher.
-    if [ "$RUN_COLLECTSTATIC" ]; then
+    echo "-----> Preparing static assets with 'collectstatic'"
 
-        echo "       Running collectstatic..."
-        python $MANAGE_FILE collectstatic --noinput  2>&1 | sed '/^Post-processed/d;/^Copying/d;/^$/d;/^ /d' | indent
+    # Run collectstatic, cleanup some of the noisy output.
+    python $MANAGE_FILE collectstatic --noinput --traceback 2>&1 | sed '/^Copying/d;/^$/d;/^ /d' | indent
+    echo
+    python $MANAGE_FILE collectstatic 2>&1 | sed '/^Copying/d;/^$/d' | indent
+    COLLECTSTATIC_STATUS="${PIPESTATUS[0]}"
+
+    set -e
+
+    # Display a warning if collectstatic failed.
+    [ $COLLECTSTATIC_STATUS -ne 0 ] && {
+        echo
+        echo " !     Error while runnning '$ python $MANAGE_FILE collectstatic --noinput'."
+        echo "       See traceback above for more details."
+        echo "       More info: http://devcenter.heroku.com/articles/django-assets"
+
+        # Additionally, dump out the environment, if debug mode is on.
+        if [ "$DEBUG_COLLECTSTATIC" ]; then
+            echo
+            echo "****** Collectstatic environment variables:"
+            echo
+            env | indent
+        fi
+
+        # Abort the build.
+        exit 1
+    }
 
-        [ $? -ne 0 ] && {
-            echo " !     Error running 'manage.py collectstatic'. More info:"
-            echo "       http://devcenter.heroku.com/articles/django-assets"
-        }
-    else
-        echo "       Collectstatic configuration error. To debug, run:"
-        echo "       $ heroku run python $MANAGE_FILE collectstatic --noinput"
-    fi
     echo
 fi
 
-bpwatch stop collectstatic
+bpwatch stop collectstatic  # metrics collection

bin/utils

@@ -88,6 +88,10 @@ sub-env() {
   WHITELIST=${2:-''}
   BLACKLIST=${3:-'^(GIT_DIR|PYTHONHOME|LD_LIBRARY_PATH|LIBRARY_PATH|PATH)$'}
 
+  # Python-specific variables.
+  export PYHONHOME=$BUILD_DIR/.heroku/python
+  export PYTHONPATH=$BUILD_DIR/
+
   (
     if [ -d "$ENV_DIR" ]; then
       for e in $(ls $ENV_DIR); do