BIND 10 #1975: implement meta-or-container-of data source

[BIND 10 Development]

#1975: implement meta-or-container-of data source
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                   Reporter:         |                 Owner:  UnAssigned
  jinmei                             |                Status:  assigned
                       Type:  task   |             Milestone:
                   Priority:         |  Sprint-20120612
  medium                             |            Resolution:
                  Component:  data   |             Sensitive:  0
  source                             |           Sub-Project:  DNS
                   Keywords:         |  Estimated Difficulty:  9
            Defect Severity:  N/A    |           Total Hours:  0
Feature Depending on Ticket:         |
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Changes (by vorner):

 * owner:  vorner => UnAssigned
 * status:  accepted => assigned


Comment:

 It is ready for review.

 But it is not complete. The interface is how it should be, but there are
 three things that need to be done and I'd like to create some follow up
 tickets for them:
  * The in-memory cache is not implemented. Only the data sources that can
 be created directly are used.
  * I want it to reuse created data sources (and caches) on re-
 configuration. Now it creates everything from scratch.
  * We need a special-case handling for loading master files.

 The amount of code is somewhat large, but it is because there are a lot of
 tests and a new interface. The amount of actual code of the class is
 pretty small.

 I don't think it needs a changelog entry, nothing is visible.

-- 
Ticket URL: <http://bind10.isc.org/ticket/1975#comment:5>
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