Apekshit Sharma 0c883a23c5 HBASE-17732 Coprocessor Design Improvements ... ------------------------------------------------------ TL;DR ------------------------------------------------------ We are moving from Inheritence - Observer *is* Coprocessor - FooService *is* CoprocessorService To Composition - Coprocessor *has* Observer - Coprocessor *has* Service ------------------------------------------------------ Design Changes ------------------------------------------------------ - Adds four new interfaces - MasterCoprocessor, RegionCoprocessor, RegionServierCoprocessor, WALCoprocessor - These new *Coprocessor interfaces have a get*Observer() function for each observer type supported by them. - Added Coprocessor#getService() to base interface. All extending *Coprocessor interfaces will get it from the base interface. - Added BulkLoadObserver hooks to RegionCoprocessorHost instad of SecureBulkLoadManager doing its own trickery. - CoprocessorHost#find*() fuctions: Too many testing hooks digging into CP internals. Deleted if can, else marked @VisibleForTesting. ------------------------------------------------------ Backward Compatibility ------------------------------------------------------ - Old coprocessors implementing *Observer won't get loaded (no backward compatibility guarantees). - Third party coprocessors only implementing Coprocessor will not get loaded (just like Observers). - Old coprocessors implementing CoprocessorService (for master/region host) /SingletonCoprocessorService (for RegionServer host) will continue to work with 2.0. - Added test to ensure backward compatibility of CoprocessorService/SingletonCoprocessorService - Note that if a coprocessor implements both observer and service in same class, its service component will continue to work but it's observer component won't work. ------------------------------------------------------ Notes ------------------------------------------------------ Did a side-by-side comparison of CPs in master and after patch. These coprocessors which were just CoprocessorService earlier, needed a home in some coprocessor in new design. For most it was clear since they were using a particular type of environment. Some were tricky. - JMXListener - MasterCoprocessor and RSCoprocessor (because jmx listener makes sense for processes?) - RSGroupAdminEndpoint --> MasterCP - VisibilityController -> MasterCP and RegionCP These were converted to RegionCoprocessor because they were using RegionCoprocessorEnvironment which can only come from a RegionCPHost. - AggregateImplementation - BaseRowProcessorEndpoint - BulkDeleteEndpoint - Export - RefreshHFilesEndpoint - RowCountEndpoint - MultiRowMutationEndpoint - SecureBulkLoadEndpoint - TokenProvider Change-Id: I813145f2bc11815f52ac703563b879962c249764		2017-09-27 12:45:51 -07:00
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src	HBASE-17732 Coprocessor Design Improvements	2017-09-27 12:45:51 -07:00
pom.xml	HBASE-18836 Note need for explicit javax.el and exclude from shaded artifacts	2017-09-18 09:53:55 -05:00