------------------------------------------------------
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
Includes partial backport of hbase-build-configuration module
Signed-off-by: Michael Stack <stack@apache.org>
Signed-off-by: Misty Stanley-Jones <misty@apache.org>
Do a pass with dependency:analyze; remove unused and
explicity list the dependencies we exploit.
Remove the parent dependencies set which had junit, mockito,
log4j, and findbugs annotations (had to put junit back
temporarily in subsequent version of this patch TODO). Listing in
parent set meant these libs were dependencies for all modules
which in practice was not the case. Edited all modules so
those that need any from this parent set now do explicit listing.
Ran the dependency:analyze over the project. Acted on most
suggested removals and requests for explicit listing. Some
grey areas remain around transitives that come in with
hadoop -needs better excludes, another project- and that
the dependency:analyze tool is not always accurate in its
reporting.
Selective add of dependency on hbase-thirdparty jars.
Update to READMEs on how protobuf is done (and update to refguide).
Removed all checked in generated protobuf files. They are generated
on the fly now as part of mainline build.
Pull in guava 22.0 by using the shaded version up in new hbase-thirdparty project.
In poms, exclude guava everywhere except on hadoop-common. Do this so
we minimize transitive includes. hadoop-common is needed because hadoop
Configuration uses guava doing preconditions.
Everywhere we used guava, instead use shaded so fix a load of imports.
Stopwatch API changed as did hashing and toStringHelper which is now
in MoreObjects class. Otherwise, minimal changes to come up on 22.0
hbase-thirdparty jars. Update to READMEs on how protobuf is done (and update to
refguide) Removed all checked in generated protobuf files. They are generatedon
the fly now as part of mainline build.
Reason for refactor:
In cases where one might need to use multiple observers, say region, master and regionserver; and the fact that only one class can be extended, it gives rise to following pattern:
public class BaseMasterAndRegionObserver
extends BaseRegionObserver
implements MasterObserver
class AccessController
extends BaseMasterAndRegionObserver
implements RegionServerObserver
were BaseMasterAndRegionObserver is full copy of BaseMasterObserver.
There is an example of simple case too where the current design fails.
Say only one observer is needed by the coprocessor, but the design doesn't permit extending even that single observer (see RSGroupAdminEndpoint), that leads to copy of full Bas
e...Observer class into coprocessor class leading to 1000s of lines of code and this ugly mix of 5 main functions with 100 useless functions.
Javadocs changes:
- Adds class comments on 'default' methods and expectations.
- Adds explanaiton of Exception handling in Observers' class comment. Removes redundant @throws before each function.
- Improves javadocs for a bunch of functions
- deletes empty @params in a bunch of places
Change-Id: I265738d47e8554e7b4678e88bb916a0cc7d00ab3
M TestStressWALProcedureStore.java
Disable test that now runs that fails because of difference in pb3.1.0.
Signed-off-by: Michael Stack <stack@apache.org>
Rely on the new plugin to do all proto generation. No need of an
external protoc setup anymore. Mvn will do it all for you.
Updated all READMEs appropriately.
Signed-off-by: Michael Stack <stack@apache.org>
This patch changes poms to use protobuf-maven-plugin instaed of
hadoop-maven-plugins generating protos. Adds a few missing READMEs too
as well as purge of unused protos turned up by the new plugin.
Apekshit Sharma
anoopsamjohn
Michael Stack
Sean Busbey
zhangduo
Chia-Ping Tsai
no_apologies
rgidwani
Guanghao Zhang
Jan Hentschel
Peter Somogyi
Jerry He
Michael Stack
Yu Li
tedyu
Enis Soztutar
Andrew Purtell