Add check_uptodate to tools/config

Add a script which can be used to validate a project's
sample config and ensure that it remains up to date on every commit.

Change-Id: Iee6cc05cad70963f2a151f595ac376c9338f5774

tools/config/README

@@ -10,3 +10,23 @@ Run it by passing the base directory and package name i.e.
 Watch out for warnings about modules like libvirt, qpid and zmq not
 being found - these warnings are significant because they result
 in options not appearing in the generated config file.
+
+
+
+This check_uptodate.sh tool is used to ensure that the generated sample
+config file in the OpenStack project source tree is continually kept up
+to date with the code itself.
+
+This can be done by adding a hook to tox.ini. For example, if a project
+already had flake8 enabled in a section like this:
+
+  [testenv.pep8]
+  commands =
+    flake8 {posargs}
+
+This section would be changed to:
+
+  [testenv.pep8]
+  commands =
+    flake8 {posargs}
+    {toxinidir}/tools/config/check_uptodate.sh

tools/config/check_uptodate.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+PROJECT_NAME=${PROJECT_NAME:-oslo}
+CFGFILE_NAME=${PROJECT_NAME}.conf.sample
+
+if [ -e etc/${PROJECT_NAME}/${CFGFILE_NAME} ]; then
+    CFGFILE=etc/${PROJECT_NAME}/${CFGFILE_NAME}
+elif [ -e etc/${CFGFILE_NAME} ]; then
+    CFGFILE=etc/${CFGFILE_NAME}
+else
+    echo "${0##*/}: can not find config file"
+    exit 1
+fi
+
+TEMPDIR=`mktemp -d /tmp/${PROJECT_NAME}.XXXXXX`
+trap "rm -rf $TEMPDIR" EXIT
+
+tools/config/generate_sample.sh -b ./ -p ${PROJECT_NAME} -o ${TEMPDIR}
+
+if ! diff -u ${TEMPDIR}/${CFGFILE_NAME} ${CFGFILE}
+then
+   echo "${0##*/}: ${PROJECT_NAME}.conf.sample is not up to date."
+   echo "${0##*/}: Please run ${0%%${0##*/}}generate_sample.sh."
+   exit 1
+fi