Add -w/--wait storage parameter, to wait for backend to be available.

neo/lib/config.py

@@ -59,6 +59,9 @@ class ConfigurationManager(object):
     def getDatabase(self):
         return self.__get('database')
 
+    def getWait(self):
+        return self.__get('wait')
+
     def getDynamicMasterList(self):
         return self.__get('dynamic_master_list', optional=True)
 

neo/scripts/neostorage.py

@@ -42,6 +42,8 @@ parser.add_option('-a', '--adapter', help = 'database adapter to use')
 parser.add_option('-d', '--database', help = 'database connections string')
 parser.add_option('-D', '--dynamic-master-list', help='path of the file '
     'containing dynamic master node list')
+parser.add_option('-w', '--wait', help='seconds to wait for backend to be '
+    'available, before erroring-out (-1 = infinite)', type='float', default=0)
 
 defaults = dict(
     name = 'storage',
@@ -61,6 +63,7 @@ def main(args=None):
         database = options.database,
         reset = options.reset,
         adapter = options.adapter,
+        wait = options.wait,
     )
     config = ConfigurationManager(
             defaults,

neo/storage/app.py

@@ -49,7 +49,7 @@ class Application(object):
         self.nm = NodeManager(config.getDynamicMasterList())
         self.tm = TransactionManager(self)
         self.dm = buildDatabaseManager(config.getAdapter(),
-            (config.getDatabase(), )
+            (config.getDatabase(), config.getWait())
         )
 
         # load master nodes

neo/storage/database/btree.py

@@ -121,8 +121,8 @@ def safeIter(func, *args, **kw):
 
 class BTreeDatabaseManager(DatabaseManager):
 
-    def __init__(self, database):
-        super(BTreeDatabaseManager, self).__init__(database)
+    def __init__(self, database, wait):
+        super(BTreeDatabaseManager, self).__init__(database, wait)
         self.setup(reset=1)
 
     @property

neo/storage/database/manager.py

@@ -25,11 +25,12 @@ class CreationUndone(Exception):
 class DatabaseManager(object):
     """This class only describes an interface for database managers."""
 
-    def __init__(self, database):
+    def __init__(self, database, wait):
         """
             Initialize the object.
         """
         self._under_transaction = False
+        self._wait = wait
         self._parse(database)
 
     def _parse(self, database):

neo/storage/database/mysqldb.py

@@ -25,6 +25,7 @@ from array import array
 from hashlib import sha1
 import re
 import string
+import time
 
 from . import DatabaseManager
 from .manager import CreationUndone
@@ -55,8 +56,8 @@ class MySQLDatabaseManager(DatabaseManager):
     # (tested with testOudatedCellsOnDownStorage).
     _use_partition = False
 
-    def __init__(self, database):
-        super(MySQLDatabaseManager, self).__init__(database)
+    def __init__(self, database, wait):
+        super(MySQLDatabaseManager, self).__init__(database, wait)
         self.conn = None
         self._config = {}
         self._connect()
@@ -79,7 +80,21 @@ class MySQLDatabaseManager(DatabaseManager):
         neo.lib.logging.info(
                         'connecting to MySQL on the database %s with user %s',
                      self.db, self.user)
-        self.conn = MySQLdb.connect(**kwd)
+        if self._wait < 0:
+            timeout_at = None
+        else:
+            timeout_at = time.time() + self._wait
+        while True:
+            try:
+                self.conn = MySQLdb.connect(**kwd)
+            except Exception:
+                if timeout_at is not None and time.time() >= timeout_at:
+                    raise
+                neo.lib.logging.exception('Connection to MySQL failed, '
+                    'retrying.')
+                time.sleep(1)
+            else:
+                break
         self.conn.autocommit(False)
         self.conn.query("SET SESSION group_concat_max_len = -1")
         self.conn.set_sql_mode("TRADITIONAL,NO_ENGINE_SUBSTITUTION")

neo/tests/storage/testReplication.py

@@ -118,7 +118,7 @@ class ReplicationTests(NeoUnitTestBase):
     def buildStorage(self, transactions, objects, name='BTree', database=None):
         def makeid(oid_or_tid):
             return pack('!Q', oid_or_tid)
-        storage = buildDatabaseManager(name, (database, ))
+        storage = buildDatabaseManager(name, (database, 0))
         storage.setup(reset=True)
         storage.setNumPartitions(1)
         storage._transactions = transactions

neo/tests/storage/testStorageBTree.py

@@ -24,7 +24,7 @@ class StorageBTreeTests(StorageDBTests):
 
     def getDB(self, reset=0):
         # db manager
-        db = BTreeDatabaseManager('')
+        db = BTreeDatabaseManager('', 0)
         db.setup(reset)
         return db
 

neo/tests/storage/testStorageMySQLdb.py

@@ -31,7 +31,7 @@ class StorageMySQSLdbTests(StorageDBTests):
         self.prepareDatabase(number=1, prefix=NEO_SQL_DATABASE[:-1])
         # db manager
         database = '%s@%s' % (NEO_SQL_USER, NEO_SQL_DATABASE)
-        db = MySQLDatabaseManager(database)
+        db = MySQLDatabaseManager(database, 0)
         db.setup(reset)
         return db
 
@@ -41,7 +41,8 @@ class StorageMySQSLdbTests(StorageDBTests):
         call.checkArgs('BEGIN')
 
     def test_MySQLDatabaseManagerInit(self):
-        db = MySQLDatabaseManager('%s@%s' % (NEO_SQL_USER, NEO_SQL_DATABASE))
+        db = MySQLDatabaseManager('%s@%s' % (NEO_SQL_USER, NEO_SQL_DATABASE),
+            0)
         # init
         self.assertEqual(db.db, NEO_SQL_DATABASE)
         self.assertEqual(db.user, NEO_SQL_USER)