I hear you on plugins, and I agree they are problematic. I went back and forth on whether to include this or not TBH.
I'll give you a couple of examples of use cases for plugins:
We have an artifact repo that can store NPM, Python and other artifacts (Nexus if you're interested). I wrote a plugin for TeamCity that can grab artifacts from a build and upload them to the repository. Obviously this can be done in a script, but there are a couple of things that make doing it in a plugin nice:
- You can set it up as a reusable build feature that can be inherited from templates (i.e. all builds of a particular type publish artifacts to Nexus)
- You can get nice UI support. The plugin contributes a tab to the build page that links to the artifacts in Nexus.
- The plugin can tie in to the build cleanup process, and remove the artifacts from the repository when the build is cleaned up. This is useful for snapshot/temporary artifacts that you want to publish so people can test with, but have automatically removed later.
Another example of where plugins have proved useful is influencing build triggering: we have some things that happen in the build server, and then other stuff happens outside of the build server. When all that completes, we then want to kick off another process in the build server (that sounds abstract - think an external deploy process runs, and once the deploy stabilizes you kick off QA jobs). In TeamCity you can write a plugin that keeps builds in the queue until the plugin reports that they are ready to run.
While plugins aren't the first tool I reach for when looking at how to provide reusable functionality in a build server, I have written several plugins for both Jenkins and TeamCity. Overall, I don't think Jenkins/TeamCity's model of having plugins run in-process is a good one, and it leads to most of the problems people have with them (although TeamCity is much better here: Jenkins basically exposes most of its guts to plugins which makes keeping the API stable virtually impossible, while TeamCity has APIs specifically designed for plugins that they've been able to keep stable very effectively) A model where a plugin was just a Docker container that communicated with the build server through some defined APIs, combined with some way for it to attach UI elements to a build that could then call back into the plugin would be much nicer. This seems to be more like what Drone is doing, but haven't played around a lot with that.
I think Gitlab has a strong philosophy of wanting to build out everything that anyone will ever need, all nicely integrated, and that's a great ideal. I think in practice, it's REALLY hard to be all things to all people. People have existing systems and/or weird use cases that it just doesn't make sense to handle all of, and plugins are a useful tool in addressing that.
If you work at gitlab, you can download the free version of TeamCity on their website. Setup a few projects and it will be obvious what it does better.
You may want to try a C#, java, python and a go projects to see the differences, with slaves on Windows and Linux. There are some pretty tight integrations for some of these.
I'll give you a couple of examples of use cases for plugins:
We have an artifact repo that can store NPM, Python and other artifacts (Nexus if you're interested). I wrote a plugin for TeamCity that can grab artifacts from a build and upload them to the repository. Obviously this can be done in a script, but there are a couple of things that make doing it in a plugin nice:
- You can set it up as a reusable build feature that can be inherited from templates (i.e. all builds of a particular type publish artifacts to Nexus)
- You can get nice UI support. The plugin contributes a tab to the build page that links to the artifacts in Nexus.
- The plugin can tie in to the build cleanup process, and remove the artifacts from the repository when the build is cleaned up. This is useful for snapshot/temporary artifacts that you want to publish so people can test with, but have automatically removed later.
Another example of where plugins have proved useful is influencing build triggering: we have some things that happen in the build server, and then other stuff happens outside of the build server. When all that completes, we then want to kick off another process in the build server (that sounds abstract - think an external deploy process runs, and once the deploy stabilizes you kick off QA jobs). In TeamCity you can write a plugin that keeps builds in the queue until the plugin reports that they are ready to run.
While plugins aren't the first tool I reach for when looking at how to provide reusable functionality in a build server, I have written several plugins for both Jenkins and TeamCity. Overall, I don't think Jenkins/TeamCity's model of having plugins run in-process is a good one, and it leads to most of the problems people have with them (although TeamCity is much better here: Jenkins basically exposes most of its guts to plugins which makes keeping the API stable virtually impossible, while TeamCity has APIs specifically designed for plugins that they've been able to keep stable very effectively) A model where a plugin was just a Docker container that communicated with the build server through some defined APIs, combined with some way for it to attach UI elements to a build that could then call back into the plugin would be much nicer. This seems to be more like what Drone is doing, but haven't played around a lot with that.
I think Gitlab has a strong philosophy of wanting to build out everything that anyone will ever need, all nicely integrated, and that's a great ideal. I think in practice, it's REALLY hard to be all things to all people. People have existing systems and/or weird use cases that it just doesn't make sense to handle all of, and plugins are a useful tool in addressing that.