Add new function get_from_global_requirements

Instead of specifying the version of a library in devstack, use the version from
global-requirements

Add new function get_from_global_requirements and use it
where it makes sense.

Change-Id: I6b2f062761ac05ef72fc6cc9993bc204faf06fa5

inc/python

@@ -95,6 +95,17 @@ function pip_install {
     fi
 }
 
+# get version of a package from global requirements file
+# get_from_global_requirements <package>
+function get_from_global_requirements {
+    local package=$1
+    local required_pkg=$(grep -h ${package} $REQUIREMENTS_DIR/global-requirements.txt | cut -d\# -f1)
+    if [[ $required_pkg == ""  ]]; then
+        die $LINENO "Can't find package $package in requirements"
+    fi
+    echo $required_pkg
+}
+
 # should we use this library from their git repo, or should we let it
 # get pulled in via pip dependencies.
 function use_library_from_git {

lib/horizon

@@ -182,8 +182,7 @@ function stop_horizon {
 # NOTE: It can be moved to common functions, but it is only used by compilation
 # of django_openstack_auth catalogs at the moment.
 function _prepare_message_catalog_compilation {
-    local babel_package=$(grep ^Babel $REQUIREMENTS_DIR/global-requirements.txt)
-    pip_install "$babel_package"
+    pip_install $(get_from_global_requirements Babel)
 }
 
 

lib/tempest

@@ -96,7 +96,8 @@ function remove_disabled_extensions {
 # configure_tempest() - Set config files, create data dirs, etc
 function configure_tempest {
     # install testr since its used to process tempest logs
-    pip_install `grep -h testrepository $REQUIREMENTS_DIR/global-requirements.txt | cut -d\# -f1`
+    pip_install $(get_from_global_requirements testrepository)
+
     local image_lines
     local images
     local num_images