X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=trunk%2Fpsycopg2%2Flib%2Fextras.py;fp=trunk%2Fpsycopg2%2Flib%2Fextras.py;h=847bdb70241448e6efc4fe651c2d27b915027d68;hb=5a4c1b1278ffa01e630fde47f7c54888ed20a576;hp=0000000000000000000000000000000000000000;hpb=cee5ab52df1c9f38b6eaff2dd354cb22f59028c7;p=plcapi.git

diff --git a/trunk/psycopg2/lib/extras.py b/trunk/psycopg2/lib/extras.py
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+"""Miscellaneous goodies for psycopg2
+
+This module is a generic place used to hold little helper functions
+and classes untill a better place in the distribution is found.
+"""
+# psycopg/extras.py - miscellaneous extra goodies for psycopg
+#
+# Copyright (C) 2003-2004 Federico Di Gregorio  <fog@debian.org>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by the
+# Free Software Foundation; either version 2, or (at your option) any later
+# version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# for more details.
+
+import os
+import time
+
+try:
+    import logging
+except:
+    logging = None
+    
+from psycopg2.extensions import cursor as _cursor
+from psycopg2.extensions import connection as _connection
+from psycopg2.extensions import register_adapter as _RA
+from psycopg2.extensions import adapt as _A
+
+
+class DictConnection(_connection):
+    """A connection that uses DictCursor automatically."""
+    def cursor(self):
+        return _connection.cursor(self, cursor_factory=DictCursor)
+
+class DictCursor(_cursor):
+    """A cursor that keeps a list of column name -> index mappings."""
+
+    __query_executed = 0
+    
+    def execute(self, query, vars=None, async=0):
+        self.row_factory = DictRow
+        self.index = {}
+        self.__query_executed = 1
+        return _cursor.execute(self, query, vars, async)
+    
+    def callproc(self, procname, vars=None):
+        self.row_factory = DictRow
+        self.index = {}
+        self.__query_executed = 1
+        return _cursor.callproc(self, procname, vars)   
+
+    def _build_index(self):
+        if self.__query_executed == 1 and self.description:
+            for i in range(len(self.description)):
+                self.index[self.description[i][0]] = i
+            self.__query_executed = 0
+            
+    def fetchone(self):
+        res = _cursor.fetchone(self)
+        if self.__query_executed:
+            self._build_index()
+        return res
+
+    def fetchmany(self, size=None):
+        res = _cursor.fetchmany(self, size)
+        if self.__query_executed:
+            self._build_index()
+        return res
+
+    def fetchall(self):
+        res = _cursor.fetchall(self)
+        if self.__query_executed:
+            self._build_index()
+        return res
+    
+    def next(self):
+        res = _cursor.fetchone(self)
+        if res is None:
+            raise StopIteration()
+        if self.__query_executed:
+            self._build_index()
+        return res
+
+class DictRow(list):
+    """A row object that allow by-colun-name access to data."""
+
+    def __init__(self, cursor):
+        self._index = cursor.index
+        self[:] = [None] * len(cursor.description)
+
+    def __getitem__(self, x):
+        if type(x) != int:
+            x = self._index[x]
+        return list.__getitem__(self, x)
+
+    def items(self):
+        res = []
+        for n, v in self._index.items():
+            res.append((n, list.__getitem__(self, v)))
+        return res
+    
+    def keys(self):
+        return self._index.keys()
+
+    def values(self):
+        return tuple(self[:])
+
+    def has_key(self, x):
+        return self._index.has_key(x)
+
+    def get(self, x, default=None):
+        try:
+            return self[x]
+        except:
+            return default
+
+
+class SQL_IN(object):
+    """Adapt any iterable to an SQL quotable object."""
+    
+    def __init__(self, seq):
+        self._seq = seq
+
+    def prepare(self, conn):
+        self._conn = conn
+    
+    def getquoted(self):
+        # this is the important line: note how every object in the
+        # list is adapted and then how getquoted() is called on it
+        pobjs = [_A(o) for o in self._seq]
+        for obj in pobjs:
+            if hasattr(obj, 'prepare'):
+                obj.prepare(self._conn)
+        qobjs = [str(o.getquoted()) for o in pobjs]
+        return '(' + ', '.join(qobjs) + ')'
+
+    __str__ = getquoted
+    
+_RA(tuple, SQL_IN)
+
+    
+class LoggingConnection(_connection):
+    """A connection that logs all queries to a file or logger object."""
+
+    def initialize(self, logobj):
+        """Initialize the connection to log to `logobj`.
+        
+        The `logobj` parameter can be an open file object or a Logger instance
+        from the standard logging module.
+        """
+        self._logobj = logobj
+        if logging and isinstance(logobj, logging.Logger):
+            self.log = self._logtologger
+        else:
+            self.log = self._logtofile
+    
+    def filter(self, msg, curs):
+        """Filter the query before logging it.
+        
+        This is the method to overwrite to filter unwanted queries out of the
+        log or to add some extra data to the output. The default implementation
+        just does nothing.
+        """
+        return msg
+    
+    def _logtofile(self, msg, curs):
+        msg = self.filter(msg, curs)
+        if msg: self._logobj.write(msg + os.linesep)
+        
+    def _logtologger(self, msg, curs):
+        msg = self.filter(msg, curs)
+        if msg: self._logobj.debug(msg)
+    
+    def _check(self):
+        if not hasattr(self, '_logobj'):
+            raise self.ProgrammingError(
+                "LoggingConnection object has not been initialize()d")
+            
+    def cursor(self):
+        self._check()
+        return _connection.cursor(self, cursor_factory=LoggingCursor)
+    
+class LoggingCursor(_cursor):
+    """A cursor that logs queries using its connection logging facilities."""
+
+    def execute(self, query, vars=None, async=0):
+        try:
+            return _cursor.execute(self, query, vars, async)
+        finally:
+            self.connection.log(self.query, self)
+
+    def callproc(self, procname, vars=None):
+        try:
+            return _cursor.callproc(self, procname, vars)  
+        finally:
+            self.connection.log(self.query, self)
+
+            
+class MinTimeLoggingConnection(LoggingConnection):
+    """A connection that logs queries based on execution time.
+    
+    This is just an example of how to sub-class LoggingConnection to provide
+    some extra filtering for the logged queries. Both the `.inizialize()` and
+    `.filter()` methods are overwritten to make sure that only queries
+    executing for more than `mintime` ms are logged.
+    
+    Note that this connection uses the specialized cursor MinTimeLoggingCursor.
+    """
+    def initialize(self, logobj, mintime=0):
+        LoggingConnection.initialize(self, logobj)
+        self._mintime = mintime
+        
+    def filter(self, msg, curs):
+        t = (time.time() - curs.timestamp) * 1000
+        if t > self._mintime:
+            return msg + os.linesep + "  (execution time: %d ms)" % t
+
+    def cursor(self):
+        self._check()
+        return _connection.cursor(self, cursor_factory=MinTimeLoggingCursor)
+    
+class MinTimeLoggingCursor(LoggingCursor):
+    """The cursor sub-class companion to MinTimeLoggingConnection."""
+
+    def execute(self, query, vars=None, async=0):
+        self.timestamp = time.time()
+        return LoggingCursor.execute(self, query, vars, async)
+    
+    def callproc(self, procname, vars=None):
+        self.timestamp = time.time()
+        return LoggingCursor.execute(self, procname, var)