[tor-bugs] #3015 [BridgeDB]: Enhance bucket functionality

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#3015: Enhance bucket functionality
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 Reporter:  kaner        |          Owner:  kaner   
     Type:  enhancement  |         Status:  assigned
 Priority:  normal       |      Milestone:          
Component:  BridgeDB     |        Version:          
 Keywords:               |         Parent:          
   Points:               |   Actualpoints:          
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Comment(by karsten):

 So, after discussing this on IRC and trying out the code, I think BridgeDB
 does ''not'' remove non-running bridges from file buckets.  At least the
 number of bridges never decreased, but always stayed the same or increased
 in my tests.  This also makes sense in the code, because Bucket.py does
 not import anything from Bridges.py, and Bridges.py is where we store
 which bridges are running.

 (I think what confused me on IRC was that when we dump bridge pool
 assignments, we look at the running bridges in Bridges.py and obtain the
 pseudo distributors from Buckets.py.  We do not, however, simply iterate
 over all the bridges in Buckets.py.  That's why we only dump pool
 assignments of running bridges.)

 The fact that we dump non-running bridges to file buckets is a bug, and we
 shouldn't fix it by only removing bridges that haven't been running for a
 day or two.  I don't see how distributing bridges via HTTPS/email or via
 Twitter/social networks is different in that we make sure we give out only
 running bridges in the former case but not in the latter.  And we do have
 the information which bridges are running, so I think we should use it.

 Here's my idea:

 We could make the BucketManager in Buckets.py, that decides which bridges
 are written to which file, extend from Bridges.BridgeHolder in the same
 way as the *Distributor classes in Dist.py do.  That's how the
 BucketManager would learn which bridges are running at the moment.

 We could also remove the command-line option to dump bridges to buckets
 and simply dump them whenever we're done reloading the network status and
 bridge descriptors.  External tools wouldn't have to run BridgeDB with the
 command-line option, but could simply read the files whenever they like.

 As a side-effect, this approach would implement the first half of #2755 by
 removing the time gap between dumping bridges to file buckets (and thereby
 possibly changing their pseudo distributors) and dumping assignments upon
 the next HUP.

 Does that make sense?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3015#comment:4>
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