list-groups: Support listing only unused groups

Author: sschuberth

gerrit/list-groups.rb

@@ -3,12 +3,15 @@
 require_relative '../bundle/bundler/setup'
 
 require 'gerry'
+require 'set'
 
-uri_str, flag = ARGV
+uri_str, *flags = ARGV
 if uri_str.nil?
     script = File.basename(__FILE__)
-    puts "Usage   : #{script} <uri>"
+    puts "Usage   : #{script} <uri> [-u]"
     puts "Example : #{script} [user:password@]host[:port]"
+    puts
+    puts "     -u   List only unused groups (those that have no associated permissions)."
     exit
 end
 
@@ -21,6 +24,28 @@
 Gerry::Client.default_options.update(verify: false)
 client = Gerry.new("#{uri.scheme}://#{uri.host}", uri.user, uri.password)
 
-client.groups.keys.each do |name|
-    puts name
+if flags.include?('-u')
+    used_groups = Set.new
+
+    client.projects.keys.each_slice(100) do |projects|
+        client.access(projects).values.each do |info|
+            info['local'].values.each do |permissions|
+                permissions['permissions'].values.each do |info|
+                    info['rules'].keys.each do |group|
+                        used_groups.add(group)
+                    end
+                end
+            end
+        end
+    end
+
+    client.groups.each do |name, info|
+        if !used_groups.include?(info['id'])
+            puts name
+        end
+    end
+else
+    client.groups.keys.each do |name|
+        puts name
+    end
 end