commit | 8c77c0fddc0b4b261ab224afa6aa01c29f3c6c50 | [log] [tgz] |
---|---|---|
author | Luca Milanesio <luca.milanesio@gmail.com> | Wed Apr 03 07:41:58 2019 +0100 |
committer | Luca Milanesio <luca.milanesio@gmail.com> | Thu Apr 04 21:30:28 2019 +0100 |
tree | 4dfc3490bb8b821b9aa99e92b068b17d3032352a | |
parent | 855f09495308cc20034f90fd77fe15adabbdc796 [diff] |
Turn the multi-site plugin into a libModule Abandon the plugin packaging style and turn the whole project into a libModule. The @PluginName annotation isn't available anymore and thus needs to be replaced with a static string. The configuration needs to be lazy loaded, otherwise it won't be possible to use straight away in the Guice module and it would risk to not be loaded at all. The EventConsumerIT test would need to be more realistic and use a real life filesystem-based configuration, so to simulate a real injection of the configuration into the Guice Module. The repackaging is needed in preparation for the injection of an alternative Git repository manager to intercept and wrap all ref-updates and check them against the shared ref-db. Re-binding the Git repository manager is done very deeply in the Gerrit daemon startup process and does not allow any modification through plugins. The introduction of a libModule allows influencing the Guice bindings at the core of Gerrit daemon startup. Change-Id: I302e2c303ca145f951426912a71e87b44082c85b
This plugin allows having multiple Gerrit masters to be deployed across various sites without having to share any storage. The alignment between the masters happens using the replication plugin and an external message broker.
The Gerrit masters requirements are:
NOTE: The multi-site plugin will not start if Gerrit is not yet migrated to NoteDb.
Currently, the only mode supported is one primary read/write master and multiple read-only masters but eventually the plan is to support N read/write masters. The read/write master is handling any traffic while the read-only masters are serving the Gerrit GUI assets, the HTTP GET REST API and the git-upload-packs. The read-only masters are kept updated to be always ready to become a read/write master.
For more details on the overall multi-site design and roadmap, please refer to the multi-site plugin DESIGN.md document
This plugin is released under the same Apache 2.0 license and copyright holders as of the Gerrit Code Review project.
The multi-site plugin is built like any other Gerrit plugin in tree mode, by cloning Gerrit and the multi-site plugin code, and checking them out on the desired branch.
Example of cloning Gerrit and multi-site for a stable-2.16 build:
git clone -b stable-2.16 https://gerrit.googlesource.com/gerrit git clone -b stable-2.16 https://gerrit.googlesource.com/plugins/multi-site cd gerrit/plugins ln -s ../../multi-site . rm external_plugin_deps.bzl ln -s multi-site/external_plugin_deps.bzl .
Example of building the multi-site plugin:
cd gerrit bazel build plugins/multi-site
The multi-site.jar plugin is generated to bazel-genfiles/plugins/multi-site/multi-site.jar
.
Example of testing the multi-site plugin:
cd gerrit bazel test plugins/multi-site:multi_site_tests
NOTE: The multi-site tests include also the use of Docker containers for instantiating and using a Kafka/Zookeeper broker. Make sure you have a Docker daemon running (/var/run/docker.sock accessible) or a DOCKER_HOST pointing to a Docker server.
Install the multi-site plugin into the $GERRIT_SITE/lib
directory of all the Gerrit servers that are part of the multi-site cluster.
Add the multi-site module to $GERRIT_SITE/etc/gerrit.config
as follows:
[gerrit] installModule = com.googlesource.gerrit.plugins.multisite.Module
Create the $GERRIT_SITE/etc/multi-site.config
on all Gerrit servers with the following basic settings:
[kafka] bootstrapServers = <kafka-host>:<kafka-port> [kafka "publisher"] enabled = true [kafka "subscriber"] enabled = true [ref-database] enabled = true [ref-database "zookeeper"] connectString = "localhost:2181"
For more details on the configuration settings, please refer to the multi-site configuration documentation.
You need also to setup the Git-level replication between nodes, for more details please refer to the replication plugin documentation.