spec-defined users and groups.

src/service/service.cr

@@ -670,9 +670,15 @@ class Service
 		@context.services.select(&.consumes?(token, self))
 	end
 
-	def user_name
+	def default_user_name
 		full_id.sub('/', '.')
 	end
+	def user_name
+		@reference.user || default_user_name
+	end
+	def group_name
+		@reference.group || default_user_name
+	end
 
 	def get_uid_gid
 		passwd = Passwd.new("/etc/passwd", "/etc/group")

src/service/service_definition.cr

@@ -81,6 +81,7 @@ class ServiceDefinition
 	getter readiness_check_command : String?
 	getter directory : String?
 	getter user : String?
+	getter group : String?
 	getter provides : String?
 	getter consumes : Array(Consumes)
 	getter environment_variables : Array(String)
@@ -101,6 +102,7 @@ class ServiceDefinition
 		@readiness_check_command = specs["readiness-check-command"]?.try &.as_s
 		@directory     = specs["directory"]?.try &.as_s
 		@user          = specs["user"]?.try &.as_s
+		@group         = specs["group"]?.try &.as_s
 		@provides      = specs["provides"]?.try &.as_a_or_s.map { |x| Provides.new x } || Array(Provides).new
 		@consumes      = specs["consumes"]?.try &.as_a_or_s.map { |x| Consumes.new x } || Array(Consumes).new
 		@environment_variables = specs["environment-variables"]?.try &.as_a_or_s || Array(String).new