[tahoe-dev] [tahoe-lafs] #833: reject mutable children when *reading* an immutable dirnode

[tahoe-lafs]

#833: reject mutable children when *reading* an immutable dirnode
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 Reporter:  warner                           |           Owner:  warner  
     Type:  defect                           |          Status:  assigned
 Priority:  critical                         |       Milestone:  1.6.0   
Component:  code-dirnodes                    |         Version:  1.5.0   
 Keywords:  integrity forward-compatibility  |   Launchpad_bug:          
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Comment(by zooko):

 Oh, what about having two separate keys next to {{{"children"}}} --
 {{{"bad_children"}}} for mutable children of an immutable directory and
 {{{"unrecognized_children"}}} for children from the future or corrupted.

 I guess it boils down to whether we want the implementation written by a
 lazy programmer to exclude the children entirely from the listing or to
 include them but not make them "live" (clickable, cd'able, cp'able, etc.)
 -- just make them "greyed-out".

 If we want them excluded, then they shouldn't appear as keys under
 {{{"children"}}} at all.  If we want them included but "greyed-out", then
 they should appear as keys under {{{"children"}}} but they should not have
 a {{{"ro_uri"}}} or {{{"rw_uri"}}} key.

 So maybe this means that mutable children of an immutable directory should
 appear in a separate {{{"bad_children"}}} key or shouldn't appear at all,
 while unrecognized children (hopefully from the future) should appear in
 the {{{"children"}}} key while having no {{{"ro_uri"}}} or {{{"rw_uri"}}}.

-- 
Ticket URL: <http://allmydata.org/trac/tahoe/ticket/833#comment:15>
tahoe-lafs <http://allmydata.org>
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