Does the with-as technique work with cx_Oracle?

Question

In recent versions of python, one can use something like with open('abc.txt') as f: to guarantee that the file is closed even if an exception occurs in the following (indented) code block. I was wondering if this technique would also work for cx_Oracle connection objects. For example, could I do something like this to guarantee the database connection gets closed if an error occurred in the subsequent code block:

with cx_Oracle.connect('uname/pwd@schema.db') as conn:
  c = conn.Cursor()
  c.execute("Select * from table1")
  #...etc

Currently I can accomplish this through the use of try...except...finally, but I prefer the with...as technique.

Answer 1

是的， Connection对象可以充当上下文管理器。

Answer 2

Even if the Connection object didn't do it itself (which apparently it does), as long as it provided a .close() method it'd be easy to make your own wrapper, using contextlib.closing

>>> from contextlib import closing
>>> 
>>> class FakeC(object):
...     def close(self):
...         print 'closing!'
...     def execute(self, cmd):
...         print cmd
... 
>>> with closing(FakeC()) as c:
...     c.execute("fred")
...     raise Exception("something went wrong!")
... 
fred
closing!
Traceback (most recent call last):
  File "<stdin>", line 3, in <module>
Exception: something went wrong!

And other variations are almost as easy.

[Wrote the above before the "Yes!" answer was posted and decided to publish it anyway.]