morro

sqlalchemy/dialects/firebird/kinterbasdb.py

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+# kinterbasdb.py
+# Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Michael Bayer mike_mp@zzzcomputing.com
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""
+The most common way to connect to a Firebird engine is implemented by
+kinterbasdb__, currently maintained__ directly by the Firebird people.
+
+The connection URL is of the form
+``firebird[+kinterbasdb]://user:password@host:port/path/to/db[?key=value&key=value...]``.
+
+Kinterbasedb backend specific keyword arguments are:
+
+type_conv
+  select the kind of mapping done on the types: by default SQLAlchemy
+  uses 200 with Unicode, datetime and decimal support (see details__).
+
+concurrency_level
+  set the backend policy with regards to threading issues: by default
+  SQLAlchemy uses policy 1 (see details__).
+
+__ http://sourceforge.net/projects/kinterbasdb
+__ http://firebirdsql.org/index.php?op=devel&sub=python
+__ http://kinterbasdb.sourceforge.net/dist_docs/usage.html#adv_param_conv_dynamic_type_translation
+__ http://kinterbasdb.sourceforge.net/dist_docs/usage.html#special_issue_concurrency
+"""
+
+from sqlalchemy.dialects.firebird.base import FBDialect, FBCompiler
+from sqlalchemy import util, types as sqltypes
+
+class _FBNumeric_kinterbasdb(sqltypes.Numeric):
+    def bind_processor(self, dialect):
+        def process(value):
+            if value is not None:
+                return str(value)
+            else:
+                return value
+        return process
+        
+class FBDialect_kinterbasdb(FBDialect):
+    driver = 'kinterbasdb'
+    supports_sane_rowcount = False
+    supports_sane_multi_rowcount = False
+    
+    supports_native_decimal = True
+    
+    colspecs = util.update_copy(
+        FBDialect.colspecs,
+        {
+            sqltypes.Numeric:_FBNumeric_kinterbasdb
+        }
+        
+    )
+    
+    def __init__(self, type_conv=200, concurrency_level=1, **kwargs):
+        super(FBDialect_kinterbasdb, self).__init__(**kwargs)
+
+        self.type_conv = type_conv
+        self.concurrency_level = concurrency_level
+
+    @classmethod
+    def dbapi(cls):
+        k = __import__('kinterbasdb')
+        return k
+
+    def create_connect_args(self, url):
+        opts = url.translate_connect_args(username='user')
+        if opts.get('port'):
+            opts['host'] = "%s/%s" % (opts['host'], opts['port'])
+            del opts['port']
+        opts.update(url.query)
+
+        type_conv = opts.pop('type_conv', self.type_conv)
+        concurrency_level = opts.pop('concurrency_level', self.concurrency_level)
+
+        if self.dbapi is not None:
+            initialized = getattr(self.dbapi, 'initialized', None)
+            if initialized is None:
+                # CVS rev 1.96 changed the name of the attribute:
+                # http://kinterbasdb.cvs.sourceforge.net/viewvc/kinterbasdb/Kinterbasdb-3.0/__init__.py?r1=1.95&r2=1.96
+                initialized = getattr(self.dbapi, '_initialized', False)
+            if not initialized:
+                self.dbapi.init(type_conv=type_conv, concurrency_level=concurrency_level)
+        return ([], opts)
+
+    def _get_server_version_info(self, connection):
+        """Get the version of the Firebird server used by a connection.
+
+        Returns a tuple of (`major`, `minor`, `build`), three integers
+        representing the version of the attached server.
+        """
+
+        # This is the simpler approach (the other uses the services api),
+        # that for backward compatibility reasons returns a string like
+        #   LI-V6.3.3.12981 Firebird 2.0
+        # where the first version is a fake one resembling the old
+        # Interbase signature. This is more than enough for our purposes,
+        # as this is mainly (only?) used by the testsuite.
+
+        from re import match
+
+        fbconn = connection.connection
+        version = fbconn.server_version
+        m = match('\w+-V(\d+)\.(\d+)\.(\d+)\.(\d+) \w+ (\d+)\.(\d+)', version)
+        if not m:
+            raise AssertionError("Could not determine version from string '%s'" % version)
+        return tuple([int(x) for x in m.group(5, 6, 4)])
+
+    def is_disconnect(self, e):
+        if isinstance(e, (self.dbapi.OperationalError, self.dbapi.ProgrammingError)):
+            msg = str(e)
+            return ('Unable to complete network request to host' in msg or
+                    'Invalid connection state' in msg or
+                    'Invalid cursor state' in msg)
+        else:
+            return False
+
+dialect = FBDialect_kinterbasdb