[Sqlalchemy-tickets] [sqlalchemy] #978: ResultProxy fetches don't wrap DBAPI exceptions

[sqlalchemy <mi...@zz...>]

#978: ResultProxy fetches don't wrap DBAPI exceptions
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 Reporter:  guest   |          Owner:  zzzeek                
     Type:  defect  |         Status:  new                   
 Priority:  medium  |      Milestone:                        
Component:  (none)  |       Severity:  no triage selected yet
 Keywords:          |   Status_field:  awaiting triage       
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 I was using SQLALchemy 0.4.3 to read a simple Oracle table in an endless
 loop when I shut down the server (on purpose). Apparently this was noticed
 after the query was executed but during the fetches on the ResultProxy.
 The resulting cx_Oracle exception was not wrapped in a subclass of
 DBAPIError. The following code reproduces the problem reliably if you have
 the server up at the start then take it down before hitting Return.


 {{{
 import sys

 from sqlalchemy import (create_engine, MetaData, Table, Column,
                         Integer, String)

 engine = create_engine(sys.argv[1])
 meta = MetaData(bind=engine)
 example = Table("example",
                 meta,
                 Column("id", Integer, primary_key=True),
                 Column("name", String(20))
                 )
 meta.drop_all()
 meta.create_all()
 example.insert().execute(id=1, name="George")
 example.insert().execute(id=2, name="Ursula")
 example.insert().execute(id=3, name="Ape")
 example.insert().execute(id=4, name="Shep")
 example.insert().execute(id=5, name="TookieTookie")

 rows = example.select().execute()
 raw_input("Type return when the server is down.")
 print list(rows)

 Type return when the server is down.
 Traceback (most recent call last):
   File "sabug.py", line 23, in <module>
     print list(rows)
   File "/tmp/SQLAlchemy-0.4.3/lib/sqlalchemy/engine/base.py", line 1533,
 in __iter__
     row = self.fetchone()
   File "/tmp/SQLAlchemy-0.4.3/lib/sqlalchemy/engine/base.py", line 1633,
 in fetchone
     row = self._fetchone_impl()
   File "/tmp/SQLAlchemy-0.4.3/lib/sqlalchemy/engine/base.py", line 1608,
 in _fetchone_impl
     return self.cursor.fetchone()
 cx_Oracle.DatabaseError: ORA-03113: end-of-file on communication channel

 }}}

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Ticket URL: <http://www.sqlalchemy.org/trac/ticket/978>
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