BIND 10 #1330: Extend DatabaseAccessor to support reading diffs

[BIND 10 Development]

#1330: Extend DatabaseAccessor to support reading diffs
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                   Reporter:         |                 Owner:
  jinmei                             |                Status:  new
                       Type:  task   |             Milestone:  Next-Sprint-
                   Priority:  major  |  Proposed
                  Component:  data   |            Resolution:
  source                             |             Sensitive:  0
                   Keywords:         |           Sub-Project:  DNS
            Defect Severity:  N/A    |  Estimated Difficulty:  0
Feature Depending on Ticket:         |           Total Hours:  0
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Comment (by jinmei):

 Replying to [comment:1 stephen]:
 > I think this needs a little more specification.  When it says "next
 "diff" in the form of RRset (in fact, essentially an "RR") ", is this:
 > * One RR for every difference, with an indication of whether the RR was
 added or removed (so if an RR has been modified, it appears twice, once as
 the old version and once as the new)?

 My intent was this one.  See also the wiki page on the difference
 design: http://bind10.isc.org/wiki/DifferenceDesign
 which I hope clarifies this point a bit better.

 Using the example shown in the "Top Level Diff Representation" section,
 the first call of getting "next diff" returns this RR:
 {{{
 example.com. SOA serial=1
 }}}
 The second call returns this:
 {{{
 a.example.com. A  192.0.2.1
 }}}
 Third returns this:
 {{{
 example.com. SOA serial=2
 }}}
 and so on.

 And since this is already IXFR-style sequence, we don't have to
 specify whether it's for "add" or "delete".

 FWIW, this is largely derived from the BIND 9's journal API.

 But I'm not necessarily insisting this particular design.

 > * Does the list of RRs include the SOA record?

 Yes.

-- 
Ticket URL: <http://bind10.isc.org/ticket/1330#comment:2>
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