Ticket #83: twisted.2.diff

File twisted.2.diff, 19.5 KB (added by davep, 13 years ago)
  • twisted/enterprise/adbapi.py

    RCS file: /cvs/Twisted/twisted/enterprise/adbapi.py,v
    retrieving revision 1.50
    diff -u -r1.50 adbapi.py
     
    2525
    2626class Transaction:
    2727    """
    28     I am a lightweight wrapper for a database 'cursor' object.  I relay
     28    I am a lightweight wrapper for a DB-API 'cursor' object.  I relay
    2929    attribute access to the DB cursor.
    3030    """
    3131    _cursor = None
     
    4646class ConnectionPool(pb.Referenceable):
    4747    """I represent a pool of connections to a DB-API 2.0 compliant database.
    4848
    49     You can pass the noisy arg which determines whether informational
    50     log messages are generated during the pool's operation.
     49    You can pass cp_min, cp_max or both to set the minimum and maximum
     50    number of connections that will be opened by the pool. You can pass
     51    the noisy arg which determines whether informational log messages are
     52    generated during the pool's operation.
    5153    """
    52     noisy = 1
    5354
    54     # XXX - make the min and max attributes (and cp_min and cp_max
    55     # kwargs to __init__) actually do something?
    56     min = 3
    57     max = 5
     55    noisy = 1   # if true, generate informational log messages
     56    min = 3     # minimum number of connections in pool
     57    max = 5     # maximum number of connections in pool
    5858
    5959    def __init__(self, dbapiName, *connargs, **connkw):
    6060        """See ConnectionPool.__doc__
    6161        """
    6262        self.dbapiName = dbapiName
    63         if self.noisy:
    64             log.msg("Connecting to database: %s %s %s" %
    65                     (dbapiName, connargs, connkw))
    6663        self.dbapi = reflect.namedModule(dbapiName)
    6764
    6865        if getattr(self.dbapi, 'apilevel', None) != '2.0':
     
    7471        self.connargs = connargs
    7572        self.connkw = connkw
    7673
    77         import thread
    78         self.threadID = thread.get_ident
    79         self.connections = {}
    80 
    8174        if connkw.has_key('cp_min'):
    8275            self.min = connkw['cp_min']
    8376            del connkw['cp_min']
     
    9083            self.noisy = connkw['cp_noisy']
    9184            del connkw['cp_noisy']
    9285
     86        self.min = min(self.min, self.max)
     87        self.max = max(self.min, self.max)
     88
     89        self.connections = {}  # all connections, hashed on thread id
     90
     91        # these are optional so import them here
     92        from twisted.python import threadpool
     93        import thread
     94
     95        self.threadID = thread.get_ident
     96        self.threadpool = threadpool.ThreadPool(self.min, self.max)
     97        self.threadpool.start()
     98
     99        # TODO: start up min connections
     100
    93101        from twisted.internet import reactor
    94102        self.shutdownID = reactor.addSystemEventTrigger('during', 'shutdown',
    95103                                                        self.finalClose)
     
    98106        """Interact with the database and return the result.
    99107
    100108        The 'interaction' is a callable object which will be executed in a
    101         pooled thread.  It will be passed an L{Transaction} object as an
    102         argument (whose interface is identical to that of the database cursor
    103         for your DB-API module of choice), and its results will be returned as
    104         a Deferred.  If running the method raises an exception, the transaction
    105         will be rolled back.  If the method returns a value, the transaction
    106         will be committed.
     109        thread using a pooled connection. It will be passed an L{Transaction}
     110        object as an argument (whose interface is identical to that of the
     111        database cursor for your DB-API module of choice), and its results
     112        will be returned as a Deferred. If running the method raises an
     113        exception, the transaction will be rolled back. If the method returns
     114        a value, the transaction will be committed.
    107115
    108116        @param interaction: a callable object whose first argument is
    109117            L{adbapi.Transaction}.
     
    117125        apply(self.interaction, (interaction,d.callback,d.errback,)+args, kw)
    118126        return d
    119127
    120     def __getstate__(self):
    121         return {'dbapiName': self.dbapiName,
    122                 'noisy': self.noisy,
    123                 'min': self.min,
    124                 'max': self.max,
    125                 'connargs': self.connargs,
    126                 'connkw': self.connkw}
     128    def runQuery(self, *args, **kw):
     129        """Execute an SQL query and return the result.
    127130
    128     def __setstate__(self, state):
    129         self.__dict__ = state
    130         apply(self.__init__, (self.dbapiName, )+self.connargs, self.connkw)
     131        A DB-API cursor will will be invoked with cursor.execute(*args, **kw).
     132        The exact nature of the arguments will depend on the specific flavor
     133        of DB-API being used, but the first argument in *args be an SQL
     134        statement. The result of a subsequent cursor.fetchall() will be
     135        fired to the Deferred which is returned. If either the 'execute' or
     136        'fetchall' methods raise an exception, the transaction will be rolled
     137        back and a Failure returned.
     138
     139        @param *args,**kw: arguments to be passed to a DB-API cursor's
     140        'execute' method.
     141
     142        @return: a Deferred which will fire the return value of a DB-API
     143        cursor's 'fetchall' method, or a Failure.
     144        """
     145
     146        d = defer.Deferred()
     147        apply(self.query, (d.callback, d.errback)+args, kw)
     148        return d
     149
     150    def runOperation(self, *args, **kw):
     151        """Execute an SQL query and return None.
     152
     153        A DB-API cursor will will be invoked with cursor.execute(*args, **kw).
     154        The exact nature of the arguments will depend on the specific flavor
     155        of DB-API being used, but the first argument in *args will be an SQL
     156        statement. This method will not attempt to fetch any results from the
     157        query and is thus suitable for INSERT, DELETE, and other SQL statements
     158        which do not return values. If the 'execute' method raises an exception,
     159        the transaction will be rolled back and a Failure returned.
     160
     161        @param *args,**kw: arguments to be passed to a DB-API cursor's
     162        'execute' method.
     163
     164        @return: a Deferred which will fire None or a Failure.
     165        """
     166
     167        d = defer.Deferred()
     168        apply(self.operation, (d.callback, d.errback)+args, kw)
     169        return d
     170
     171    def close(self):
     172        """Close all pool connections and shutdown the pool.
     173
     174        Connections will be closed even if they are in use!
     175        """
     176
     177        from twisted.internet import reactor
     178        reactor.removeSystemEventTrigger(self.shutdownID)
     179        self.finalClose()
     180
     181    def finalClose(self):
     182        """This should only be called by the shutdown trigger."""
     183
     184        self.threadpool.stop()
     185        for connection in self.connections.values():
     186            if self.noisy:
     187                log.msg('adbapi closing: %s %s%s' % (self.dbapiName,
     188                                                     self.connargs or '',
     189                                                     self.connkw or ''))
     190            connection.close()
     191        self.connections.clear()
    131192
    132193    def connect(self):
    133         """Should be run in thread, blocks.
     194        """Return a database connection when one becomes available. This method blocks and should be run in a thread from the internal threadpool.
    134195
    135196        Don't call this method directly from non-threaded twisted code.
     197
     198        @return: a database connection from the pool.
    136199        """
     200
    137201        tid = self.threadID()
    138202        conn = self.connections.get(tid)
    139         if not conn:
     203        if conn is None:
     204            if self.noisy:
     205                log.msg('adbapi connecting: %s %s%s' % (self.dbapiName,
     206                                                        self.connargs or '',
     207                                                        self.connkw or ''))
    140208            conn = apply(self.dbapi.connect, self.connargs, self.connkw)
    141209            self.connections[tid] = conn
    142             if self.noisy:
    143                 log.msg('adbapi connecting: %s %s%s' %
    144                     ( self.dbapiName, self.connargs or '', self.connkw or ''))
    145210        return conn
    146211
     212    def _runInteraction(self, interaction, *args, **kw):
     213        trans = Transaction(self, self.connect())
     214        try:
     215            result = apply(interaction, (trans,)+args, kw)
     216            trans.close()
     217            trans._connection.commit()
     218            return result
     219        except:
     220            log.msg('Exception in SQL interaction. Rolling back.')
     221            log.deferr()
     222            trans._connection.rollback()
     223            raise
     224
    147225    def _runQuery(self, args, kw):
    148226        conn = self.connect()
    149227        curs = conn.cursor()
     
    154232            conn.commit()
    155233            return result
    156234        except:
     235            log.msg('Exception in SQL query. Rolling back.')
     236            log.deferr()
    157237            conn.rollback()
    158238            raise
    159239
    160240    def _runOperation(self, args, kw):
    161241        conn = self.connect()
    162242        curs = conn.cursor()
    163 
    164243        try:
    165244            apply(curs.execute, args, kw)
    166             result = None
    167245            curs.close()
    168246            conn.commit()
    169247        except:
    170             # XXX - failures aren't working here
     248            log.msg('Exception in SQL operation. Rolling back.')
     249            log.deferr()
    171250            conn.rollback()
    172251            raise
    173         return result
     252
     253    def __getstate__(self):
     254        return {'dbapiName': self.dbapiName,
     255                'noisy': self.noisy,
     256                'min': self.min,
     257                'max': self.max,
     258                'connargs': self.connargs,
     259                'connkw': self.connkw}
     260
     261    def __setstate__(self, state):
     262        self.__dict__ = state
     263        apply(self.__init__, (self.dbapiName, )+self.connargs, self.connkw)
     264
     265    def deferToThread(self, f, *args, **kwargs):
     266        """Internal function.
     267
     268        Call f in one of the connection pool's threads.
     269        """
     270
     271        d = defer.Deferred()
     272        self.threadpool.callInThread(threads._putResultInDeferred,
     273                                     d, f, args, kwargs)
     274        return d
    174275
    175276    def query(self, callback, errback, *args, **kw):
    176277        # this will be deprecated ASAP
    177         threads.deferToThread(self._runQuery, args, kw).addCallbacks(
     278        self.deferToThread(self._runQuery, args, kw).addCallbacks(
    178279            callback, errback)
    179280
    180281    def operation(self, callback, errback, *args, **kw):
    181282        # this will be deprecated ASAP
    182         threads.deferToThread(self._runOperation, args, kw).addCallbacks(
     283        self.deferToThread(self._runOperation, args, kw).addCallbacks(
    183284            callback, errback)
    184285
    185286    def synchronousOperation(self, *args, **kw):
     
    187288
    188289    def interaction(self, interaction, callback, errback, *args, **kw):
    189290        # this will be deprecated ASAP
    190         apply(threads.deferToThread,
     291        apply(self.deferToThread,
    191292              (self._runInteraction, interaction) + args, kw).addCallbacks(
    192293            callback, errback)
    193294
    194     def runOperation(self, *args, **kw):
    195         """Run a SQL statement and return a Deferred of result."""
    196         d = defer.Deferred()
    197         apply(self.operation, (d.callback,d.errback)+args, kw)
    198         return d
    199 
    200     def runQuery(self, *args, **kw):
    201         """Run a read-only query and return a Deferred."""
    202         d = defer.Deferred()
    203         apply(self.query, (d.callback, d.errback)+args, kw)
    204         return d
    205 
    206     def _runInteraction(self, interaction, *args, **kw):
    207         trans = Transaction(self, self.connect())
    208         try:
    209             result = apply(interaction, (trans,)+args, kw)
    210         except:
    211             log.msg('Exception in SQL interaction!  rolling back...')
    212             log.deferr()
    213             trans._connection.rollback()
    214             raise
    215         else:
    216             trans._cursor.close()
    217             trans._connection.commit()
    218             return result
    219 
    220     def close(self):
    221         from twisted.internet import reactor
    222         reactor.removeSystemEventTrigger(self.shutdownID)
    223         self.finalClose()
    224 
    225     def finalClose(self):
    226         for connection in self.connections.values():
    227             if self.noisy:
    228                 log.msg('adbapi closing: %s %s%s' % (self.dbapiName,
    229                                                      self.connargs or '',
    230                                                      self.connkw or ''))
    231             connection.close()
    232295
    233296class Augmentation:
    234297    '''A class which augments a database connector with some functionality.
     
    242305
    243306    def __init__(self, dbpool):
    244307        self.dbpool = dbpool
    245         #self.createSchema()
    246308
    247309    def __setstate__(self, state):
    248310        self.__dict__ = state
    249         #self.createSchema()
    250311
    251312    def operationDone(self, done):
    252313        """Example callback for database operation success.
  • twisted/test/test_enterprise.py

    RCS file: /cvs/Twisted/twisted/test/test_enterprise.py,v
    retrieving revision 1.16
    diff -u -r1.16 test_enterprise.py
     
    2222import os
    2323import random
    2424
    25 from twisted.trial.util import deferredResult
    2625from twisted.enterprise.row import RowObject
    2726from twisted.enterprise.reflector import *
    2827from twisted.enterprise.xmlreflector import XMLReflector
    2928from twisted.enterprise.sqlreflector import SQLReflector
    3029from twisted.enterprise.adbapi import ConnectionPool
    3130from twisted.enterprise import util
     31from twisted.internet import defer
     32from twisted.trial.util import deferredResult, deferredError
     33from twisted.python import log
    3234
    3335try: import gadfly
    3436except: gadfly = None
     
    8991)
    9092"""
    9193
     94simple_table_schema = """
     95CREATE TABLE simple (
     96  x integer
     97)
     98"""
     99
    92100def randomizeRow(row, nullsOK=1, trailingSpacesOK=1):
    93101    values = {}
    94102    for name, type in row.rowColumns:
     
    298306    DB_USER = 'twisted_test'
    299307    DB_PASS = 'twisted_test'
    300308
     309    can_rollback = 1
     310
    301311    reflectorClass = SQLReflector
    302312
    303313    def createReflector(self):
     
    305315        self.dbpool = self.makePool()
    306316        deferredResult(self.dbpool.runOperation(main_table_schema))
    307317        deferredResult(self.dbpool.runOperation(child_table_schema))
     318        deferredResult(self.dbpool.runOperation(simple_table_schema))
    308319        return self.reflectorClass(self.dbpool, [TestRow, ChildRow])
    309320
    310321    def destroyReflector(self):
    311322        deferredResult(self.dbpool.runOperation('DROP TABLE testTable'))
    312323        deferredResult(self.dbpool.runOperation('DROP TABLE childTable'))
     324        deferredResult(self.dbpool.runOperation('DROP TABLE simple'))
    313325        self.dbpool.close()
    314326        self.stopDB()
    315327
    316     def startDB(self): pass
    317     def stopDB(self): pass
     328    def testPool(self):
     329        # make sure failures are raised correctly
     330        deferredError(self.dbpool.runQuery("select * from NOTABLE"))
     331        deferredError(self.dbpool.runOperation("delete from * from NOTABLE"))
     332        deferredError(self.dbpool.runInteraction(self.bad_interaction))
     333        log.flushErrors()
     334
     335        # verify simple table is empty
     336        sql = "select count(1) from simple"
     337        row = deferredResult(self.dbpool.runQuery(sql))
     338        self.failUnless(int(row[0][0]) == 0, "Interaction not rolled back")
     339
     340        # add some rows to simple table (runOperation)
     341        for i in range(self.count):
     342            sql = "insert into simple(x) values(%d)" % i
     343            deferredResult(self.dbpool.runOperation(sql))
     344
     345        # make sure they were added (runQuery)
     346        sql = "select x from simple order by x";
     347        rows = deferredResult(self.dbpool.runQuery(sql))
     348        self.failUnless(len(rows) == self.count, "Wrong number of rows")
     349        for i in range(self.count):
     350            self.failUnless(len(rows[i]) == 1, "Wrong size row")
     351            self.failUnless(rows[i][0] == i, "Values not returned.")
     352
     353        # runInteraction
     354        deferredResult(self.dbpool.runInteraction(self.interaction))
     355
     356        # give the pool a workout
     357        ds = []
     358        for i in range(self.count):
     359            sql = "select x from simple where x = %d" % i
     360            ds.append(self.dbpool.runQuery(sql))
     361        dlist = defer.DeferredList(ds, fireOnOneErrback=1)
     362        result = deferredResult(dlist)
     363        for i in range(self.count):
     364            self.failUnless(result[i][1][0][0] == i, "Value not returned")
     365
     366        # now delete everything
     367        ds = []
     368        for i in range(self.count):
     369            sql = "delete from simple where x = %d" % i
     370            ds.append(self.dbpool.runOperation(sql))
     371        dlist = defer.DeferredList(ds, fireOnOneErrback=1)
     372        deferredResult(dlist)
     373
     374        # verify simple table is empty
     375        sql = "select count(1) from simple"
     376        row = deferredResult(self.dbpool.runQuery(sql))
     377        self.failUnless(int(row[0][0]) == 0, "Interaction not rolled back")
     378
     379    def interaction(self, transaction):
     380        transaction.execute("select x from simple order by x")
     381        for i in range(self.count):
     382            row = transaction.fetchone()
     383            self.failUnless(len(row) == 1, "Wrong size row")
     384            self.failUnless(row[0] == i, "Value not returned.")
     385        # should test this, but gadfly throws an exception instead
     386        #self.failUnless(transaction.fetchone() is None, "Too many rows")
     387
     388    def bad_interaction(self, transaction):
     389        if self.can_rollback:
     390            transaction.execute("insert into simple(x) values(0)")
    318391
     392        transaction.execute("select * from NOTABLE")
    319393
    320 class SinglePool(ConnectionPool):
    321     """A pool for just one connection at a time.
    322     Remove this when ConnectionPool is fixed.
    323     """
    324 
    325     def __init__(self, connection):
    326         self.connection = connection
    327 
    328     def connect(self):
    329         return self.connection
    330 
    331     def close(self):
    332         self.connection.close()
    333         del self.connection
     394    def startDB(self): pass
     395    def stopDB(self): pass
    334396
    335397
    336398class NoSlashSQLReflector(SQLReflector):
     
    346408    nullsOK = 0
    347409    DB_DIR = "./gadflyDB"
    348410    reflectorClass = NoSlashSQLReflector
     411    can_rollback = 0
    349412
    350413    def startDB(self):
    351414        if not os.path.exists(self.DB_DIR): os.mkdir(self.DB_DIR)
     
    359422        conn.close()
    360423
    361424    def makePool(self):
    362         return SinglePool(gadfly.gadfly(self.DB_NAME, self.DB_DIR))
     425        return ConnectionPool('gadfly', self.DB_NAME, self.DB_DIR, cp_max=1)
    363426
    364427
    365428class SQLiteTestCase(SQLReflectorTestCase, unittest.TestCase):
     
    375438        if os.path.exists(self.database): os.unlink(self.database)
    376439
    377440    def makePool(self):
    378         return SinglePool(sqlite.connect(database=self.database))
     441        return ConnectionPool('sqlite', database=self.database, cp_max=1)
    379442
    380443
    381444class PostgresTestCase(SQLReflectorTestCase, unittest.TestCase):
     
    384447
    385448    def makePool(self):
    386449        return ConnectionPool('pyPgSQL.PgSQL', database=self.DB_NAME,
    387                               user=self.DB_USER, password=self.DB_PASS)
     450                              user=self.DB_USER, password=self.DB_PASS,
     451                              cp_min=0)
    388452
    389453
    390454class MySQLTestCase(SQLReflectorTestCase, unittest.TestCase):
     
    392456    """
    393457
    394458    trailingSpacesOK = 0
     459    can_rollback = 0
    395460
    396461    def makePool(self):
    397462        return ConnectionPool('MySQLdb', db=self.DB_NAME,
     
    410475
    411476
    412477if gadfly is None: GadflyTestCase.skip = 1
     478elif not getattr(gadfly, 'connect', None): gadfly.connect = gadfly.gadfly
     479
    413480if sqlite is None: SQLiteTestCase.skip = 1
    414481
    415482if PgSQL is None: PostgresTestCase.skip = 1