* merge druid-core, extendedset, and druid-hll into druid-processing to simplify everything
* fix poms and license stuff
* mockito is evil
* allow reset of JvmUtils RuntimeInfo if tests used static injection to override
* remove use of mocks for ServiceMetricEvent
* simplify KafkaEmitterTests by moving to Mockito
* speed up KafkaEmitterTest by adjusting reporting frequency in tests
* remove unnecessary easymock and JUnitParams dependencies
* prometheus-emitter
* use existing jetty server to expose prometheus collection endpoint
* unused variables
* better variable names
* removed unused dependencies
* more metric definitions
* reorganize
* use prometheus HTTPServer instead of hooking into Jetty server
* temporary empty help string
* temporary non-empty help. fix incorrect dimension value in JSON (also updated statsd json)
* added full help text. added metric conversion factor for timers that are not using seconds. Correct metric dimension name in documentation
* added documentation for prometheus emitter
* safety for invalid labelNames
* fix travis checks
* Unit test and better sanitization of metrics names and label values
* add precondition to check namespace against regex
* use precompiled regex
* remove static imports. fix metric types
* better docs. fix possible NPE in PrometheusEmitterConfig. Guard against multiple calls to PrometheusEmitter.start()
* Update regex for label-value replacements to allow internal numeric values. Additional tests
* Adds missing license header
updates website/.spelling to add words used in prometheus-emitter docs.
updates docs/operations/metrics.md to correct the spelling of
bufferPoolName
* fixes version in extensions-contrib/prometheus-emitter
* fix style guide errors
* update import ordering
* add another word to website/.spelling
* remove unthrown declared exception
* remove unused import
* Pushgateway strategy for metrics
* typo
* Format fix and nullable strategy
* Update pom file for prometheus-emitter
* code review comments. Counter to gauge for cache metrics, periodical task to pushGateway
* Syntax fix
* Dimension label regex include numeric character back, fix previous commit
* bump prometheus-emitter pom dev version
* Remove scheduled task inside poen that push metrics
* Fix checkstyle
* Unit test coverage
* Unit test coverage
* Spelling
* Doc fix
* spelling
Co-authored-by: Michael Schiff <michael.schiff@tubemogul.com>
Co-authored-by: Michael Schiff <schiff.michael@gmail.com>
Co-authored-by: Tianxin Zhao <tianxin.zhao@tubemogul.com>
Co-authored-by: Tianxin Zhao <tizhao@adobe.com>