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POasyncore callbacks launching threads... ok to do?
 

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    <p>I'm unfamiliar with <a href="http://docs.python.org/library/asyncore.html" rel="nofollow">asyncore</a>, and have very limited knowledge of asynchronous programming except for a few intro to twisted tutorials.</p> <p>I am most familiar with threads and use them in all my apps. One particular app uses a <a href="http://www.couchone.com/" rel="nofollow">couchdb</a> database as its interface. This involves longpolling the db looking for changes and updates. The module I use for couchdb is <a href="http://couchdbkit.org/" rel="nofollow">couchdbkit</a>. It uses an asyncore loop to watch for these changes and send them to a callback. </p> <p>So, I figure from this callback is where I launch my worker threads. It seems a bit crude to mix asynchronous and threaded programming. I really like couchdbkit, but would rather not introduce issues into my program.</p> <p>So, my question is, is it safe to fire threads from an async callback?</p> <p>Here's some code...</p> <pre><code>def dispatch(change): global jobs, db_url # jobs is my queue db = Database(db_url) work_order = db.get(change['id']) # change is an id to the document that changed. # i need to get the actual document (workorder) worker = Worker(work_order, db) # fire the thread jobs.append(worker) worker.start() return main() . . . consumer.wait(cb=dispatch, since=update_seq, timeout=10000) #wait constains the asyncloop. </code></pre> <p>Update:</p> <p>After looking over this more, I have an additional question for the couchdbkit gurus. There will potentially be hundreds of threads using the database. As you can see in my code sample, I am instantiating a couchdbkit.Database object per thread. I think this may be wasteful. So, is it ok for a single database object to be used globally among the threads? </p>
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