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Comment by samueloph | Hacker News Reader

Jenkins has some serious problems when you want to work with CD.

Its currently impossible* to use Jenkins in a CD environment where you want to deploy by tagging your git project[1] and allow rollbacks because Jenkins doesn't treat tag's hashes (only the commits the tag points to).

Unfortunately, hack such a fix is not very pleasant either, because Java, and i don't think the Jenkins developers are interested in it either, at least not if just a few people ask for it.

It may look as a silly usecase, but i believe its one that mostly fits when you have a dynamic server farm (hosting on aws with autoscalling, for example) and don't want to auto-deploy on master commit.

[1]https://groups.google.com/d/msg/jenkinsci-users/mYxtDNMz1ZI/...

edit-> * aktually its not impossible, but pretty hacky and ugly, it would be nice to be able to rely on jenkins own tools for this.

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> Jenkins has some serious problems when you want to work with CD.

When you want to work with CD in a particular way.

A simple fix to the above issue would be to have a "production" branch. When you want to do a release, you merge to the production branch. A roll back would just be a revert of the commits since the last merge to production, and could even be tagged.

If you are doing CD by allowing devs to tag random branches, cool, but I would not call it a "failure" on the Jenkins side.

> Unfortunately, hack such a fix is not very pleasant either, because Java, and i don't think the Jenkins developers are interested in it either, at least not if just a few people ask for it.

Its a webhook - that can be in any language, or if you use Git(hub|lab) a config item.

>> Jenkins has some serious problems when you want to work with CD.

> When you want to work with CD in a particular way.

> A simple fix to the above issue would be to have a "production" branch. When you want to do a release, you merge to the production branch. A roll back would just be a revert of the commits since the last merge to production, and could even be tagged.

> If you are doing CD by allowing devs to tag random branches, cool, but I would not call it a "failure" on the Jenkins side.

Well, i must confess i agree with you and my first idea was this, i will probably end up pushing for that anyway, but i will have to convince some devs that they should not be afraid of git reverts. When i first mentioned the idea, some devs with deploy rights said they were skeptical about this because they were afraid of having a git revert shitstorm in a SOS situation.

>> Unfortunately, hack such a fix is not very pleasant either, because Java, and i don't think the Jenkins developers are interested in it either, at least not if just a few people ask for it.

> Its a webhook - that can be in any language, or if you use Git(hub|lab) a config item.

Not exactly, on this case github only lets me create webhooks with 'create' action, which is trigerred "Any time a Branch or Tag is created.", so new branches would trigger deploys.

> When you want to work with CD in a particular way.

I think that I, as the user of the project, should get to decide how I want to deploy my software. So, yes, I do want to CD things in a particular way: one that matches my developer's expectations and my business requirements.

> CD

Jenkins isn't a deployment tool. It can act like one, but this (rollback) is a classic example of how it's a build, not release, tool.

To address OP's complaint: we rebuild steps from the previous pipeline to perform a rollback, and we have all our deployment logic in a separate system which works with commit IDs, if the previous pipeline has been pushed out of the list of recent pipeline runs.

> I think that I, as the user of the project, should get to decide how I want to deploy my software. So, yes, I do want to CD things in a particular way: one that matches my developer's expectations and my business requirements.

Sure - it definitely is. But we all have to do that within the limitations of the tools we use. Jenkins makes an assumption (in the default mode) of a continuously moving HEAD - which may or may not be what you want. It doesn't make Jenkins bad - it makes it not suitable for your use case.

FWIW - adapting to using a moving HEAD is not that hard - `git reset <old-tag> && git commit -a -m "Revert deploy <failed-tag> && git tag <failed-tag+1> && git push` - but I totally understand why people would not like to use that style. It is a personal / culture choice.

> i don't think the Jenkins developers are interested in it either

I keep running into this: we want to extend or change Jenkins behaviour, and since it's open-source, it's possible to get up-to-speed on the codebase & make that change. But getting it into a state which matches the mindset of the project maintainers is tough! Trying to convince someone that your use-case is not only permissible but is actually a good idea over ticket comments is not what we want to spend our time on.

I'm the creator of Jenkins.

Without fully knowing the context, I wonder if this is just a simple disconnect.

In Jenkins, we collectively cover wide-ranging use cases not by making one existing plugin (say Git plugin) do everything, but by making it extensible so that other people can define additional semantics and behaviours as separate plugins on top of it.

We learned this in the early days of Subversion plugin, back when that was the most popular version control system. Everyone uses a generic tool like that very differently, so as we kept adding individually valid use cases to the Subversion plugin, it became this giant hair ball not just for devs but also for users.

This mode also works better for those who do not want to spend time explaining why their use case is a good/important one, as they can simply code up their idea as a separate plugin and move on.

With all that said, I'm sorry for the frustration you had. Do you still have some pointers to tickets/PRs, etc? I'd like to look into it.

Hi, thanks for responding!

Funnily enough, I'm specifically thinking of the Git plugin and issues like https://issues.jenkins-ci.org/browse/JENKINS-6124 & https://issues.jenkins-ci.org/browse/JENKINS-14572, and Nicholas de Loof's comments 'ur doin it wrong'. It's extremely difficult to extend this plugin; we have a lot of work tracking all the existing plugins we use, and adding maintenance of our own plugin on top of that is work we don't want to do.

Nowadays we try to keep as little as possible defined in jenkins configs and put our build & test logic in makefiles/tools.

Yeah - it is a "problem"[0] with open source - you need to deal with people that may have completely objectives to you.

It is easier with a closed source / paid service to ask for feature requests. Remember that the maintainers probably get hundreds of similar requests a week, and have merged things in the past that they didn't like and later caused issues.

This causes confirmation bias for them "The last time we allowed code not aligned to codeing styles / test requirements / feature direction / $reason it all went badly", so it is easier to ask for things to align to their world view before merging it.

Being a maintainer is hard - you are damned if you do, and damned if you don't. People give out about not merging code, but they also give out if the code that does get merged breaks things. Finding a balance is hard.

0 - I don't personally think it is a problem, but it potentially requires a bigger time investment, and can be infuriating when you have a small change that really scratches an itch for you.

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