Sqlalchemy.exc.UnboundExecutionError: Impossibile trovare un vicolo cieco configurato sul mapper Mapper | SellsTable | venditori o questa Sessione

Question

creo una classe per lavorare con SQLAlchemy:

class DbAbsLayer(object): 
    def __init__(self): 
     self.setConnectionURI(); 
    def setConnectionURI(self): 
     self.dbDriver = "mysql"; 
     self.dbHostname = "localhost"; 
     self.dbUsername = "root"; 
     self.dbPassword = "123"; 
     self.dbName = "mydbname"; 
    def createSession(self): 
     Session = sessionmaker(); 
     self.session = Session.configure(); 
     self.session = Session(); 
    def createEngine(self): 
     self.setConnectionURI(); 
     self.engine = create_engine(self.dbDriver + "://" + self.dbUsername + ":" + self.dbPassword + "@" + self.dbHostname + "/" + self.dbName); 

Poi ho creato il mio classe tabella:

class SellsTable(declarative_base()): 
    __tablename__ = 'sellers'; #  
    id = Column(Integer,primary_key = True) 
    name = Column(String) 
    name_type = Column(Integer) 
    address = Column(String) 
    telephones = Column(String) 
    emails = Column(String) 
    job_background = Column(String) 
    agent_first_name = Column(String) 
    agent_last_name = Column(String)  
    agent_attributes = Column(String) 
    agent_values = Column(String) 

suo costruttore:

def __init__(self,fieldsName ,fieldsValue): 
    completeVariableName = list(); 
    tmpKeysOfFieldsValue = fieldsValue.keys(); 
    for fieldsNameCounter in range (0,len(fieldsName)): 
     for filedsValueCounter in range(0,len(tmpKeysOfFieldsValue)): 
      if fieldsName[fieldsNameCounter] == tmpKeysOfFieldsValue[filedsValueCounter]: 
       completeVariableName.append("self." + tmpKeysOfFieldsValue[filedsValueCounter]); 
       tmpVariable = completeVariableName[filedsValueCounter]; 
       tmpValue = fieldsValue[fieldsName[fieldsNameCounter]]; 
       exec ('%s = \"%s\"' % (tmpVariable, tmpValue)); 

ho la seguente funzione per l'aggiunta di record:

def addRecord(self,tableObj): 
    TableClass = tableObj.__class__ ; 
    sessionObj = TableClass(['name','telephones'],dict([('name','golrang'),('telephones','092127878,21078288')])); 
    self.session.add(sessionObj); ##### MY ERROR LINE 
    self.session.commit(); 

Ma quando ho eseguito aggiungere func, ricevo il seguente traccia posteriore:

Traceback (most recent call last): 
    File "./main.py", line 218, in <module> 
    main() 
    File "./main.py", line 210, in main 
    dbObj.addRecord(ddd); 
    File "./main.py", line 104, in addRecord 
    self.session.commit(); 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 721, in commit 
    self.transaction.commit() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 354, in commit 
    self._prepare_impl() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 334, in _prepare_impl 
    self.session.flush() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 1818, in flush 
    self._flush(objects) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 1936, in _flush 
    transaction.rollback(_capture_exception=True) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/util/langhelpers.py", line 58, in __exit__ 
    compat.reraise(exc_type, exc_value, exc_tb) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 1900, in _flush 
    flush_context.execute() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/unitofwork.py", line 372, in execute 
    rec.execute(self) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/unitofwork.py", line 525, in execute 
    uow 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/persistence.py", line 45, in save_obj 
    uowtransaction) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/persistence.py", line 140, in _organize_states_for_save 
    states): 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/persistence.py", line 772, in _connections_for_states 
    base_mapper) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 211, in connection 
    bind = self.session.get_bind(bindkey, **kwargs) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 1102, in get_bind 
    ', '.join(context))) 
sqlalchemy.exc.UnboundExecutionError: Could not locate a bind configured on mapper Mapper|SellsTable|sellers or this Session 

Answer 1

Si dovrebbe legare il motore al modello.

class DbAbsLayer(object): 

    def createSession(self): 
     Session = sessionmaker() 
     self.session = Session.configure(bind=self.engine)