Question

I want to make a single database object available across many python modules.

For a related example, I create globl.py:

DOCS_ROOT="c:\docs" ## as an example
SOLR_BASE="http://localhost:8636/solr/"

Any other module which needs it can do a

from globl import DOCS_ROOT

Now this example aside, I want to do the same thing with database connection objects, share them across many modules.

import MySQLdb
conn = MySQLdb.connect (host="localhost"...)
cursor = conn.cursor()

I tried this on the interpreter:

from globl import cursor

and it seems to work. But I suspect that this will cause the same module to be executed each time one imports from it. So is this the proper way?

Answer 1

You suspect wrongly. The code will only be executed once – subsequent imports just refer to the module via sys.modules, and don’t re-run it.

(Note that this is the case as long as you always use the same path to import the module – if you do from globl import cursor in one place, and from my.fullyqualified.project.global import cursor in another, you probably will find the code is re-executed.)

Edit to add as S.Lott says in the comment, this is a perfectly good way to handle a global object.