[tahoe-dev] [tahoe-lafs] #677: WebAPI: GET /uri/$FILECAP?t=json doesn't return size for mutable files, but the HTML version does

[tahoe-lafs]

#677: WebAPI: GET /uri/$FILECAP?t=json doesn't return size for mutable files, but
the HTML version does
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 Reporter:  soult              |           Owner:           
     Type:  defect             |          Status:  new      
 Priority:  trivial            |       Milestone:  undecided
Component:  code-frontend-web  |         Version:  1.3.0    
 Keywords:                     |   Launchpad_bug:           
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Comment(by warner):

 yeah, get_size_of_best_version() is fairly new, and the JSON-rendering
 code was written before it was available. Also, I seem to remember that
 requiring a Deferred to get that size was annoying, and I didn't want to
 slow down a directory listing by doing a mapupdate for every single
 mutable file therein.

 For CHK files, the size is stored in the filecap, so it's trivial to get
 it. For mutable files, you have to ask around and find out what versions
 are available. This "mapupdate" operation isn't as expensive as actually
 retrieving the file's contents, but it's close (a roundtrip or two).

 Your approach sounds reasonable. Be sure to think about whether it's
 t=JSON on a single file that gets this fix, and/or t=JSON on a whole
 directory (which might not be a good idea, if there are lots of mutable
 files in it). It'd probably be better to leave the "size" field out of the
 elements of a directory fetch than to include "?" strings.

-- 
Ticket URL: <http://allmydata.org/trac/tahoe/ticket/677#comment:2>
tahoe-lafs <http://allmydata.org>
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