Auto generate minimal environment variables doc

This script will generate the minimal-environment-variables doc
based on the what each services has in the check_required_var field.
Anytime that field is changed run this script and commit the changes.
Since Neutron is a thick container, the script will get a few duplicates
in the neutron-agents field.  When Neutron is thinned out, this script
will function normally.

Closes-bug: #1459347

Co-Authored-By: Lon Hohberger <lhh@redhat.com>
Change-Id: I1ba6bd5148af12cacfd872591b3c7b84a8dccba2

1 files changed, 68 insertions, 0 deletions

diff --git a/tools/min-env.sh b/tools/min-env.sh
new file mode 100755
index 000000000..403a43c34
--- /dev/null
+++ b/tools/min-env.sh
@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+#
+# This script generates the minimal environment variable doc
+
+# Move to top level directory
+REAL_PATH=$(python -c "import os,sys;print os.path.realpath('$0')")
+cd "$(dirname "$REAL_PATH")/.."
+
+DOC=docs/minimal-environment-vars.md
+DOCKERDIR="docker"
+# BASE and TYPE can be hard coded to centos and rdo since the required vars will always be the same
+BASE="centos"
+TYPE="rdo"
+
+function write_header {
+    local header=$1
+    header=${header^}
+    header=$(echo ${header} | sed -e 's/-app//')
+    echo -e "\n# $header\n" >> "$DOC"
+}
+
+function write_env_var {
+    local env_var=$1
+    if [ -z "$env_var" ]; then
+        echo "" >> "$DOC"
+    else
+        env_var=${env_var%=*}
+        echo "    $env_var" >> "$DOC"
+    fi
+}
+
+function find_vars {
+    local img_location=$1
+    local empty=true
+    scripts=$(find ${img_location} -name *.sh | sort -t / -k 4)
+
+    for script in $scripts; do
+        local vars=$(awk '/^\s*check_required_vars/,/([^\\]\s*$)/' $script)
+        vars=$(echo "$vars" | sed 's/check_required_vars//' | sed 's/\\//g')
+
+        if [ ! -z "$vars" ]; then
+            empty=false
+            for v in $vars; do
+                write_env_var $v
+            done
+        fi
+    done
+
+    if $empty; then
+        echo "    None" >> "$DOC"
+    fi
+}
+
+cat > $DOC <<EOF
+# Environment Variables
+
+In order for each service to function, there is a minimum set of required variables that need to be plugged into the environment.  Below is the list of variables that is needed for each service to run in a minimal setting.
+EOF
+
+declare -a startsh
+startsh=$(find "${DOCKERDIR}/${BASE}/${TYPE}/" -name Dockerfile | sort -t / -k 4 | grep -v data)
+
+for start_script in $startsh; do
+    if [ ! "$(dirname $start_script | xargs basename)" == "base" ]; then
+        write_header $(dirname $start_script | xargs basename)
+        find_vars $(dirname $start_script) $(dirname $start_script | xargs basename)
+    fi
+done