I disagree because:

1. It is not a bug
2. it is not a regression at all

Categories apply to items only, but the "/categories" endpoint does not mention it in paths.

This endpoint is not valid, the right endpoint is: JENKINS_ROOT/PATH_VIEW/categories where PATH_VIEW can be:

1. empty: JENKINS_ROOT/categories
2. or for example: JENKINS_ROOT/view/custom/categories

The meaning is Please, give me the item categories and its items availables in this view.

The endpoint may conflict with existing closed-source plugins. E.g. I had the Categorization plugin at one of my previous companies, which used the similar endpoint. Update to 2.0 will cause regressions in such plugins

Is this really an argument? As contributor of Jenkins core I have to thing about possible proprietary developments. This is crazy! Why something like itemCategories is a valid option?

The implementation is not pluggable. E.g. Views and Items cannot filter the categories somehow

This is a new requirement we can implement in the future. By the way, Items are being filtered.

> empty: JENKINS_ROOT/categories

So in such case it overlaps with the corner-case I've provided

> Is this really an argument? As contributor of Jenkins core I have to thing about possible proprietary developments. This is crazy!

You are not supposed to think about them. That's why we have Jenkins 2.0 beta testing, because it allows users to notify us about such issues. It does not mean that we must fix such issues, but at least it worths some discussion

Daniel Beck your PoV here would be great!

Closed-source plugins are not an argument to me. I'm not even sure open-source plugins would be a major argument to impede core development, depending on exactly what the problem is. They would just be fixed. Otherwise, no detaching JUnit plugin from core in 1.577, or ever.

However, Oleg does have a point with the confusion regarding what the categories are for. So a rename to itemCategories to support e.g. viewCategories besides it, seems straightforward enough. FWIW I was a big proponent for generic categorization from the beginning, Jenkins users typically have more view types than item types.

> Closed-source plugins are not an argument to me. I'm not even sure open-source plugins would be a major argument to impede core development, depending on exactly what the problem is. They would just be fixed.

IMHO it does not well comply with the "this guy is fully compatible, no reason not to upgrade" statement we declare for 2.0. I'm OK if we don't fix in this case, but there maybe corner cases. Maybe we should explicitly recommend testing before upgrading.

Oleg Nenashev By the way, the renaming involves to send a new PR to cloudbees-folder-plugin ref.

Jesse Glick Do you agree with the change proposed? Remember that this change involves to change this again.

Yes go ahead and change categories to itemCategories. I was holding off on a cloudbees-folder release until you did so, so that I can make the matching change.

Oleg Nenashev working in progress....

Manuel Recena Soto Thanks a lot!

Oleg Nenashev Done.

Code changed in jenkins
User: recena
Path:
core/src/main/java/hudson/model/View.java
war/src/main/js/add-item.js
http://jenkins-ci.org/commit/jenkins/4a5b825b479d56beb0717bfb1cbcb659c51557fb
Log:
JENKINS-33972 The REST API URL has been removed to [..]/itemCategories

Code changed in jenkins
User: Daniel Beck
Path:
core/src/main/java/hudson/model/View.java
war/src/main/js/add-item.js
http://jenkins-ci.org/commit/jenkins/4649e04cbe58f5af0e583da04084b2ebc442a320
Log:
Merge pull request #2208 from recena/JENKINS-33972

JENKINS-33972 The REST API URL has been removed to [..]/itemCategories

Compare: https://github.com/jenkinsci/jenkins/compare/0db4bc2a6327...4649e04cbe58

Code changed in jenkins
User: Jesse Glick
Path:
src/main/java/com/cloudbees/hudson/plugins/folder/FolderAddFilter.java
http://jenkins-ci.org/commit/cloudbees-folder-plugin/dab943292bcc6121c62701cb62307edce09c6d31
Log:
JENKINS-33972 View.doCategories renamed to doItemCategories.

Code changed in jenkins
User: Jesse Glick
Path:
src/main/java/com/cloudbees/hudson/plugins/folder/FolderAddFilter.java
http://jenkins-ci.org/commit/cloudbees-folder-plugin/526694d36b9d2e0685ceac9c168204a209969b3d
Log:
Merge pull request #54 from jglick/itemCategories-JENKINS-33972

JENKINS-33972 View.doCategories renamed to doItemCategories

#55 is identical, just merging the lower-numbered one.

Compare: https://github.com/jenkinsci/cloudbees-folder-plugin/compare/6f2daf46be91...526694d36b9d

Code changed in jenkins
User: recena
Path:
src/main/java/com/cloudbees/hudson/plugins/folder/FolderAddFilter.java
http://jenkins-ci.org/commit/cloudbees-folder-plugin/c3ba1ab0efab2552003752af46d659504b69c3e5
Log:
JENKINS-33972 View.doCategories was renamed to View.doItemCategories

Code changed in jenkins
User: Jesse Glick
Path:
http://jenkins-ci.org/commit/cloudbees-folder-plugin/ac521be9372a056a799c354e75f5ce33d516b7ff
Log:
Merge pull request #55 from recena/JENKINS-33972

JENKINS-33972 View.doCategories was renamed to View.doItemCategories

Heck, merge them both, see if GitHub can handle it!

Compare: https://github.com/jenkinsci/cloudbees-folder-plugin/compare/526694d36b9d...ac521be9372a