Make ansible unbuffered for better experience while logging

util/vagrant/upgrade.sh

@@ -168,6 +168,12 @@ if [[ -f ${OPENEDX_ROOT}/app/edx_ansible/server-vars.yml ]]; then
   SERVER_VARS="--extra-vars=\"@${OPENEDX_ROOT}/app/edx_ansible/server-vars.yml\""
 fi
 
+# When tee'ing to a log, ansible (like many programs) buffers its output. This
+# makes it hard to tell what is actually happening during the upgrade.
+# "stdbuf -oL" will run ansible with line-buffered stdout, which makes the
+# messages scroll in the way people expect.
+ANSIBLE_PLAYBOOK="sudo stdbuf -oL ansible-playbook --inventory-file=localhost, --connection=local "
+
 make_config_venv () {
   virtualenv venv
   source venv/bin/activate
@@ -209,9 +215,7 @@ EOF
 
   echo "Upgrading to the end of Django 1.4"
   cd configuration/playbooks/vagrant
-  sudo ansible-playbook \
-    --inventory-file=localhost, \
-    --connection=local \
+  $ANSIBLE_PLAYBOOK \
     $SERVER_VARS \
     --extra-vars="edx_platform_version=release-2015-11-09" \
     --extra-vars="xqueue_version=named-release/cypress" \
@@ -229,9 +233,7 @@ EOF
 
   echo "Upgrading to the beginning of Django 1.8"
   cd configuration/playbooks/vagrant
-  sudo ansible-playbook \
-    --inventory-file=localhost, \
-    --connection=local \
+  $ANSIBLE_PLAYBOOK \
     $SERVER_VARS \
     --extra-vars="edx_platform_version=dogwood-first-18" \
     --extra-vars="xqueue_version=dogwood-first-18" \
@@ -268,9 +270,7 @@ if [[ $TARGET == *eucalyptus* ]] ; then
 
   echo "Upgrade the code"
   cd configuration/playbooks/vagrant
-  sudo ansible-playbook \
-    --inventory-file=localhost, \
-    --connection=local \
+  $ANSIBLE_PLAYBOOK \
     $SERVER_VARS \
     --extra-vars="edx_platform_version=$TARGET" \
     --extra-vars="xqueue_version=$TARGET" \
@@ -296,9 +296,7 @@ echo "ora2_version: $TARGET" >> vars.yml
 echo "certs_version: $TARGET" >> vars.yml
 echo "forum_version: $TARGET" >> vars.yml
 echo "xqueue_version: $TARGET" >> vars.yml
-sudo ansible-playbook \
-    --inventory-file=localhost, \
-    --connection=local \
+$ANSIBLE_PLAYBOOK \
     --extra-vars="@vars.yml" \
     $SERVER_VARS \
     vagrant-$CONFIGURATION.yml