Add server support for customizing the backend storage file

This change updates the server, adding in support for customizing
the backend storage file used to store all server data. The server
currently uses a simple SQLite database for storage. Prior versions
of the server kept this database file in /tmp, to emphasize the
testing focus of the server. This change loosens that restriction,
now allowing users to customize where the database file lives. A
new configuration option, 'database_path', has been added that will
override the default /tmp location for the database file. This
value can also be passed in if invoking the server via script using
the '-d' flag.

kmip/services/server/server.py

@@ -45,6 +45,7 @@ class KmipServer(object):
     shutting down all server components upon receiving a termination signal.
     """
 
+    # TODO (peter-hamilton) Move to using **kwargs for all server parameters.
     def __init__(
             self,
             hostname=None,
@@ -59,7 +60,8 @@ class KmipServer(object):
             enable_tls_client_auth=None,
             tls_cipher_suites=None,
             logging_level=None,
-            live_policies=False
+            live_policies=False,
+            database_path=None
     ):
         """
         Create a KmipServer.
@@ -123,6 +125,8 @@ class KmipServer(object):
                 policy directory should be actively monitored to autoload any
                 policy changes while the server is running. Optional, defaults
                 to False.
+            database_path (string): The path to the server's SQLite database
+                file. Optional, defaults to None.
         """
         self._logger = logging.getLogger('kmip.server')
         self._setup_logging(log_path)
@@ -139,7 +143,8 @@ class KmipServer(object):
             policy_path,
             enable_tls_client_auth,
             tls_cipher_suites,
-            logging_level
+            logging_level,
+            database_path
         )
         self.live_policies = live_policies
         self.policies = {}
@@ -188,7 +193,8 @@ class KmipServer(object):
             policy_path=None,
             enable_tls_client_auth=None,
             tls_cipher_suites=None,
-            logging_level=None
+            logging_level=None,
+            database_path=None
     ):
         if path:
             self.config.load_settings(path)
@@ -219,6 +225,8 @@ class KmipServer(object):
             )
         if logging_level:
             self.config.set_setting('logging_level', logging_level)
+        if database_path:
+            self.config.set_setting('database_path', database_path)
 
     def start(self):
         """
@@ -252,7 +260,8 @@ class KmipServer(object):
         self.policy_monitor.start()
 
         self._engine = engine.KmipEngine(
-            policies=self.policies
+            policies=self.policies,
+            database_path=self.config.settings.get('database_path')
         )
 
         self._logger.info("Starting server socket handler.")
@@ -604,6 +613,18 @@ def build_argument_parser():
             "DEBUG, INFO). Optional, defaults to None."
         )
     )
+    parser.add_option(
+        "-d",
+        "--database_path",
+        action="store",
+        type="str",
+        default=None,
+        dest="database_path",
+        help=(
+            "A string representing a path to the server's SQLite database "
+            "file. Optional, defaults to None."
+        ),
+    )
 
     return parser
 
@@ -636,6 +657,8 @@ def main(args=None):
         kwargs['enable_tls_client_auth'] = False
     if opts.logging_level:
         kwargs['logging_level'] = opts.logging_level
+    if opts.database_path:
+        kwargs['database_path'] = opts.database_path
 
     kwargs['live_policies'] = True