new rdbms config item sqlite_timeout...

...makes the previously hard-coded timeout of 30 seconds
configurable. This is the time a client waits for the locked database
to become free before giving up. Used only for SQLite backend.

Author: Ralf Schlatterbeck

CHANGES.txt

@@ -13,6 +13,10 @@ Features:
   title with the changed subject. Thanks to Arkadiusz Kita and Peter
   Funk for requesting the feature and discussing the implementation.
   http://thread.gmane.org/gmane.comp.bug-tracking.roundup.user/10169
+- new rdbms config item sqlite_timeout makes the previously hard-coded
+  timeout of 30 seconds configurable. This is the time a client waits
+  for the locked database to become free before giving up. Used only for
+  SQLite backend.
 
 Fixed:
 

roundup/backends/back_sqlite.py

@@ -75,11 +75,11 @@ class Database(rdbms_common.Database):
 
     def sqlite_busy_handler(self, data, table, count):
         """invoked whenever SQLite tries to access a database that is locked"""
+        now = time.time()
         if count == 1:
-            # use a 30 second timeout (extraordinarily generous)
-            # for handling locked database
-            self._busy_handler_endtime = time.time() + 30
-        elif time.time() > self._busy_handler_endtime:
+            # Timeout for handling locked database (default 30s)
+            self._busy_handler_endtime = now + self.config.RDBMS_SQLITE_TIMEOUT
+        elif now > self._busy_handler_endtime:
             # timeout expired - no more retries
             return 0
         # sleep adaptively as retry count grows,
@@ -100,13 +100,13 @@ def sql_open_connection(self):
 
         db = os.path.join(self.config.DATABASE, 'db')
         logging.getLogger('hyperdb').info('open database %r'%db)
-        # set a 30 second timeout (extraordinarily generous) for handling
-        # locked database
+        # set timeout (30 second default is extraordinarily generous)
+        # for handling locked database
         if sqlite_version == 1:
             conn = sqlite.connect(db=db)
             conn.db.sqlite_busy_handler(self.sqlite_busy_handler)
         else:
-            conn = sqlite.connect(db, timeout=30)
+            conn = sqlite.connect(db, timeout=self.config.RDBMS_SQLITE_TIMEOUT)
             conn.row_factory = sqlite.Row
 
         # pysqlite2 / sqlite3 want us to store Unicode in the db but

roundup/configuration.py

@@ -604,6 +604,10 @@ def str2value(self, value):
         (NullableOption, 'read_default_group', 'roundup',
             "Name of the group to use in the MySQL defaults file (.my.cnf).\n"
             "Only used in MySQL connections."),
+        (IntegerNumberOption, 'sqlite_timeout', '30',
+            "Number of seconds to wait when the SQLite database is locked\n"
+            "Default: use a 30 second timeout (extraordinarily generous)\n"
+            "Only used in SQLite connections."),
         (IntegerNumberOption, 'cache_size', '100',
             "Size of the node cache (in elements)"),
     ), "Settings in this section are used"