All,

If it's ok, I'd like to post a bit of code on here with the hope of getting a bit of help. What i'm attempting to do is create a simple database layer for all of my applications to traffic data in and out of my ZODB. I'm writing quite a few different apps, 10+ and growing, that all work with the same data. I've created a simple "newData" function that should decide what sort of data the incoming data is and arrange it in the database in an organized manner. The idea with all of this is if I want to change the way my database works, I don't have to change it across 10+ applications. I've taken a lot of the other methods out to simplify the post.


My current problem with the code is that as I'll try to insert say 150 objects into the db, and then verify that those objects have been inserted into the db with another application. It appears as if they're being inserted in the application that's doing the insertions, but the "reader" app can only see a handful (<10) objects have been inserted. The odd thing is that every time i ask the "insertion" application to insert these 150 objects, the "reader" can see a handful more. It's as if the ZODB listens to my request to insert the first few objects, but the newer transactions after a certain point. Any help is really appreciated!

Regards,
Kenneth Miller


from This.That import Thing,Blirp,Thingy,Thingamajig,Something

class Layer:
    def __init__(self,host,port):
"""A layer for trafficing Teledrill data types in and out of a ZODB through a ZEO client.
        host - the hostname
        port - the port
        """

        self.host = host
        self.port = port
        self.addr = self.host,self.port
        self.lf = '/tmp/mwdlf'

        self.connect()

        #the below is an excellect way to wipe out your DB
        #if not self.verifyIntegrity():
        #    self.createDBSystem()

    def connect(self):
        """Connect the layer to the underlying database."""
        from ZEO import ClientStorage
        from ZEO import Exceptions
        from ZODB import DB

self.storage = ClientStorage.ClientStorage(self.addr,wait=False) #try to connect, don't wait
        self.db = DB(self.storage)
        self.conn = self.db.open()
        self.root = self.conn.root()


    def disconnect(self):
        self.conn.close()
        self.db.close()
        self.storage.close()

    def verifyIntegrity(self):
        root = self.connect()

        #sync the DB
        #get the BTrees
        from BTrees import OOBTree
        from persistent.list import PersistentList
        #make sure the proper data containers exist
        try:
            if not isinstance(self.root['rawdata'],OOBTree.OOBTree):
                return False
            if not isinstance(self.root['things1'],OOBTree.OOBTree):
                return False
            if not isinstance(self.root['things2'],OOBTree.OOBTree):
                return False
            if not isinstance(self.root['things3'],OOBTree.OOBTree):
                return False
            if not isinstance(self.root['things4'],OOBTree.OOBTree):
                return False
            if not isinstance(self.root['things5'],OOBTree.OOBTree):
                return False
        except KeyError:
            return False

        #self.disconnect()
        #if all else
        return True

    def createDBSystem(self):
        #get the transaction module

        #root = self.connect()

        import transaction
        #and our BTrees and PL
        from BTrees import OOBTree
        from persistent.list import PersistentList
        #Create the containers
        self.root['rawdata'] = OOBTree.OOBTree()
        self.root['things1'] =  OOBTree.OOBTree()
        self.root['things2'] = OOBTree.OOBTree()
        self.root['things3'] = OOBTree.OOBTree()
        self.root['things4'] = OOBTree.OOBTree()
        self.root['things5'] = OOBTree.OOBTree()
        #make the changes permanent
        transaction.commit()



    def newData(self,data):

        print "Incoming Data!"
        #if we can iterate over the data
        try:
            for d in data:
                self.newData(d) #iterate over the elements individual
            return True
        except TypeError:
            pass

        import transaction

        #validate the object
        myErr = ValueError('Data has no timeStamp attached!')

        try:
            if data.timeStamp==None:
                raise myErr
        except AttributeError, e:
            print e
            raise myErr

        newKey = data.timeStamp

        if isinstance(data,Blirp.Blirp):
            print "It's a blirp!"
            if self.root['blirps'].has_key(newKey):
                print "They key already exists!", newKey
                raise KeyError('Data Exists!',newKey,data)
            else:
                print "Trying to insert!"
while(not self.root['blirps'].insert(newKey,data)): print 'Try!'
                print 'Done!'
            print len(self.root['blirps'])

        print "Committing"
        transaction.commit()

        return True

_______________________________________________
For more information about ZODB, see the ZODB Wiki:
http://www.zope.org/Wikis/ZODB/

ZODB-Dev mailing list  -  ZODB-Dev@zope.org
http://mail.zope.org/mailman/listinfo/zodb-dev

Reply via email to