Support Apache IoTDB as a storage option, mostly refer to previous InfluxDB storage option.
* The Design of Apache IoTDB Storage Option, https://skywalking.apache.org/blog/2021-11-23-design-of-iotdb-storage-option/

Fix ElasticSearch implementation of `queryMetricsValues` and `readLabeledMetricsValues` doesn't fill default values (#8012)

* Fix ElasticSearch implementation of `queryMetricsValues` and `readLabeledMetricsValues` doesn't fill default values
* Change generated file path.

Add a GraphQL query to get OAP version, display OAP version in startup message and error logs (#8004)

* [maven-release-plugin] prepare release v8.8.0

* [maven-release-plugin] prepare for next development iteration

* Create changes-8.8.0.md

* Reset changelog for 8.9.0

* [maven-release-plugin] prepare release v8.7.0

* [maven-release-plugin] prepare for next development iteration

* [maven-release-plugin] prepare release v8.4.0

* [maven-release-plugin] prepare for next development iteration

* [maven-release-plugin] prepare release v8.3.0

* [maven-release-plugin] prepare for next development iteration

* [maven-release-plugin] prepare release v8.2.0

* [maven-release-plugin] prepare for next development iteration

* [maven-release-plugin] prepare release v8.1.0

* [maven-release-plugin] prepare for next development iteration

* [maven-release-plugin] prepare release v8.0.0

* [maven-release-plugin] prepare for next development iteration

* Remove all shardingsphere cases.

* [maven-release-plugin] prepare release v7.0.0

* [maven-release-plugin] prepare for next development iteration

Motivation:

Review code styles with some bots automatically.

Modifications:

Set up ReviewDog in GitHub Action to review code style.

Add more check rules to checkstyle plugin.

Result:

Obvious code styles can be reviewed and commented automatically.

* [maven-release-plugin] prepare release v6.6.0

* [maven-release-plugin] prepare for next development iteration

* [Feature] Officially support ElasticSearch 7 as backend storage

* Extract bootstrap module to be shared by multiple starters

* Add missing configuration file and distinguish different version in test

* Update known-oap-backend-dependencies-es7.txt

Update the dependency lib

* Fix missing adaptation to ElasticSearch 7

* Rename ElasticSearch 7 specific class with Es7 infix

* Fix miss-adapted ElasticSearch DAO API

* Add ES7 specific configuration and polish documentations

* Polish documentations

* Polish documentations

* [maven-release-plugin] prepare release v6.5.0

* [maven-release-plugin] prepare for next development iteration

* Is it a typo or not?

* delete datasource-settings.properties

* handle 'metadataQueryMaxSize'

* delete DynamicModuleConfig.java

* modify mysql config

* parsing yaml to support the configuration for multiple properties

* delete datasource-settings.properties

* modify doc

* add properties for docker-entrypoint.sh

* add testLoadConfig()

* Provide Consul dynamic configuration center implementation

* Add more unit tests

* Fix unit test

* Add more unit tests and remove unused file

* Remove redundant doc

* [maven-release-plugin] prepare release v6.4.0

* [maven-release-plugin] prepare for next development iteration

* Remove the meta file

* [maven-release-plugin] prepare release v6.3.0

* [maven-release-plugin] prepare for next development iteration

* Support etcd configuration.

* First commit

* Fix e2e test and some nits

* Documenting so11y and setting default values of it in dev env

* Change OAL generator tool to runtime.

Step 1. change project structure. API links and maven pom.

* Part of metrics class generation

* Metrcis class generated.

* Set up the basic structure of new OAL engine.

* Finish metrics generation.

* Support dispatcher generation.

* Format codes.

* Generate dispatcher all methods.

* Implement disable in hardcode.

* Clear up

* Fix compile startup.

* Update license and document of new OAL engine.

* Fix rat.

* Disable class output in default

* Copy from @kezhenxu94 's test PR, https://github.com/apache/skywalking/pull/3110

* Wait for the mount command to finish

* [maven-release-plugin] prepare release v6.2.0

* [maven-release-plugin] prepare for next development iteration

* configration-zookeeper

* Add cluster-etcd-plugin

* Provide Apollo dynamic configuration center implementation. fixes #2825

* Provide Nacos dynamic configuration center implementation. fixes #2816

* Add unit tests

* Sync

* Replace pull-mode with watch-mode

* Fix ci

* Unify dependency management

* Add integration tests

* Revert unexpected changes

* Add more test cases

* Revert unexpected changes

* Suppress IDE warning

* Correctify volumes position

* Add license header

* Remove Chinese comments

* Sync

* Sync

* Sync

* Sync

* Revert unexpected changes

* Rebase on refactored code and add missing config to docker

* Fix unit test

* Revert unnecessary changes

* Implement the base of config API module.

* Finish configuration module codebases w/o tests, revert some changes.

* Finish mock tests.

* Add new gRPC service for configuration.

* Make gRPC configuration sync provider works.

* Add database slow statement dynamic setting.

* Finish the dynamic configuration service.

* Fix version.

* Fix #2546

* Change the stackdepth type

* Fix bug

* Fix CI failed

* fix #2599

* fix ci

* add license

* add ActiveTag error methods

* fix

* fix

* nacos

* nacos

* nacos

* nacos

* fix ci

* support nacos cluster

* fix yml

* fix license

* fix ci

* remove optional

* update license

* update license and doc

* fix