contrib exit messages

clean up the error messages in the contrib script. well... to be more
precise, actually _add_ some error messages to the script.

contrib/pre-commit-hook-static-dba-files.sh

@@ -19,20 +19,23 @@
 echoerr() { echo "$@" 1>&2; }
 
 # Utility function to exit if last command exited non-zero.
-exit_if_err() {
-  if [[ $? -ne 0 ]]
-  then
+ensure() {
+  if [[ $? -ne 0 ]] ; then
+    echoerr "Could not execute task: $1"
+    echoerr "Exiting..."
     exit 1
   fi
 }
 
 
-# The schema-tool has to be run from the directory where config.json lives,
-# which may not be the same location as where the root of the project.  So, we
-# have to move the working directory of the script to the location of
-# config.json (which is the same real path as this hook), but before doing so
-# save the current working directory to a variable so that Git operations can
-# be performed.
+# This part is a bit tricky. In terms of getting the correct directories to
+# work with. This makes the assumption that the alters sit in the root of the
+# directory. This may not always be the case, but we can't reliably call `pwd`
+# from this context. Sometimes git (seemingly) changes up the root directory
+# of where the hooks are called from. Because of this we have to be limited
+# to this assumption.
+#
+# If you need to change this, simply edit ORIG_DIR below
 
 HOOK_DIR="$( cd "$(dirname "$0")" ; pwd -P  )"
 ORIG_DIR="$HOOK_DIR/../.."
@@ -79,17 +82,17 @@ do
   SEEN+=($NODE)
 
   UP_RESULT=$(schema gen-sql -q -w $NODE)
-  exit_if_err
+  ensure "Generate UP alter for $NODE"
 
   DOWN_RESULT=$(schema gen-sql -q -w -d $NODE)
-  exit_if_err
+  ensure "Generate DOWN alter for $NODE"
 
   # Add the up and down files to git
   ADD_UP=$(cd $ORIG_DIR && git add "$UP_RESULT")
-  exit_if_err
+  ensure "Add $UP_RESULT to git"
 
   ADD_DOWN=$(cd $ORIG_DIR && git add "$DOWN_RESULT")
-  exit_if_err
+  ensure "Add $DOWN_RESULT to git"
 
   echo "Added file to commit (up):   $UP_RESULT"
   echo "Added file to commit (down): $DOWN_RESULT"