Add metric change tracking scripts.

postgres-metrics-get-changes.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+# Script to parse a text exposition format file into a unique list of metrics
+# output by the exporter and then build lists of added/removed metrics.
+
+old_src="$1"
+[ ! -e "$old_src" ] && exit 1
+
+function generate_add_removed() {
+    type="$1"
+    pg_version="$2"
+    old_version="$3"
+    new_version="$4"
+    
+    comm -23 "$old_version" "$new_version" > ".metrics.${type}.${pg_version}.removed"
+    comm -13 "$old_version" "$new_version" > ".metrics.${type}.${pg_version}.added"   
+}
+
+for raw_prom in $(echo .*.prom) ; do
+    # Get the type and version
+    type=$(cut -d'.' -f3)
+    pg_version=$(cut -d'.' -f4)
+
+    unique_file="${raw_prom}.unique"
+    old_unique_file="$old_src/$unique_file"
+
+    # Strip, sort and deduplicate the label names
+    grep -v '#' "$raw_prom" | \
+        rev | cut -d' ' -f2- | \
+        rev | cut -d'{' -f1 | \
+        sort | \
+        uniq > "$unique_file"
+    
+    generate_add_removed "$type" "$pg_version" "$old_unique_file" "$unique_file"
+done