move to a verb-based architecture

backupmgr/__main__.py

@@ -6,7 +6,7 @@ import json
 from . import application
 
 def main():
-    return application.Application().run()
+    return application.Application(sys.argv[1:]).run()
 
 if __name__ == "__main__":
     sys.exit(main())

backupmgr/application.py

@@ -15,6 +15,9 @@ class Application(object):
     def logger(self):
         return package_logger().getChild("application")
 
+    def __init__(self, argv):
+        self.argv = argv
+
     def configure_logging(self):
         logging.basicConfig()
         l = package_logger()
@@ -31,9 +34,9 @@ class Application(object):
         backend_types.load_backend_types()
 
     def load_config(self):
-        self.config = configuration.read_config()
+        self.config = configuration.Config(self.argv, "backupmgr")
         self.email_handler.toaddr = self.config.notification_address
-        if self.config.quiet:
+        if self.config.config_options.quiet:
             self.stderr_handler.disable()
 
     def prepare_backups(self):
@@ -47,17 +50,26 @@ class Application(object):
     def finalize(self):
         self.email_handler.finalize()
 
+    def perform_backups(self):
+        backups = self.prepare_backups()
+        backup_successes = []
+        for backup in backups:
+            if backup.perform():
+                backup_successes.append(backup)
+        self.log_backups(backup_successes)
+        self.logger.info("Successfully completed {}/{} backups.".format(len(backup_successes), len(backups)))
+
+    def unknown_verb(self):
+        raise Exception("Unknown verb")
+
     def run(self):
+        verbs = {
+            "backup": self.perform_backups
+        }
         try:
             self.bootstrap()
             self.load_config()
-            backups = self.prepare_backups()
-            backup_successes = []
-            for backup in backups:
-                if backup.perform():
-                    backup_successes.append(backup)
-            self.log_backups(backup_successes)
-            self.logger.info("Successfully completed {}/{} backups.".format(len(backup_successes), len(backups)))
+            verbs.get(self.config.config_options.verb, self.unknown_verb)()
         except error.Error as e:
             self.logger.fatal(e.message)
             sys.exit(1)

backupmgr/configuration.py

@@ -142,11 +142,20 @@ class Config(object):
     def default_state(self):
         return {}
 
-    def __init__(self):
-        parser = argparse.ArgumentParser()
-        parser.add_argument("-q", "--quiet", action="store_true")
-        ns = parser.parse_args()
-        self.quiet = ns.quiet
+    def parse_args(self):
+        parser = argparse.ArgumentParser(prog=self.prog)
+        parser.add_argument("-q", "--quiet", action="store_true", 
+                            help="Be quiet on logging to stdout/stderr")
+        subparsers = parser.add_subparsers()
+        parser_backup = subparsers.add_parser("backup")
+        parser_backup.set_defaults(verb="backup")
+        return parser.parse_args(self.argv)
+
+    def __init__(self, argv, prog):
+        self.argv = argv
+        self.prog = prog
+        ns = self.parse_args()
+        self.config_options = ns
 
         self.configfile = CONFIG_LOCATION
         try:
@@ -253,6 +262,3 @@ class Config(object):
             if backup.should_run(self.last_run_of_backup(backup)):
                 backups_to_run.append(backup)
         return backups_to_run
-
-def read_config():
-    return Config()