CFE-4686: Add cancel attribute to classes promises to undefine a class#6175
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nickanderson wants to merge 2 commits into
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CFE-4686: Add cancel attribute to classes promises to undefine a class#6175nickanderson wants to merge 2 commits into
nickanderson wants to merge 2 commits into
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Covers undefining a defined class when the cancel expression is true, retaining the class when the expression is false, function-based triggers, the no-op case for an undefined class, refusal to cancel reserved hard classes, and mutual exclusion with the class-defining attributes. Ticket: CFE-4686 Changelog: None Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Until now a classes promise could only define a class; the only way to undefine one from policy was a cancel_* classes body attached to another promise's outcome. This adds a 'cancel' attribute to the classes promise itself: when its class expression (a string, or a function returning a boolean) evaluates true, the promiser class is undefined if it is defined. The class-skipping optimization in ExpandDeRefPromise() normally excludes a classes promise whose promiser is already defined. A cancel promise must run precisely in that case, so the skip now makes an exception when the 'cancel' attribute is present. 'cancel' is mutually exclusive with the class-defining attributes (expression, and, or, xor, not, dist, select_class) via the existing "Irreconcilable constraints" check, since it is counted like any other class-body attribute. Reserved hard classes cannot be cancelled. The evaluation and undefine path mirrors the cancel_* classes body behaviour (DeleteAllClasses). Ticket: CFE-4686 Changelog: Title Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Author
|
@cf-bottom jenkins please |
![github-advanced-security[bot]](https://avatars.githubusercontent.com/in/57789?s=60&v=4){kind=small}
| boolean. Shared by the class-defining attributes (expression, not, and, or, | ||
| xor, select_class, dist) and by the class-cancelling 'cancel' attribute, | ||
| whose trigger is evaluated exactly like 'expression'. This deliberately does | ||
| NOT consider whether the promiser class is already defined; that skip logic |
| " ?> Cancelling cached persistent class %s", | ||
| pp->promiser); | ||
| EvalContextHeapPersistentRemove(pp->promiser); | ||
| } |
| pp->promiser); | ||
| EvalContextHeapPersistentRemove(pp->promiser); | ||
| } | ||
| return false; |
|
Alright, I triggered a build: Jenkins: https://ci.cfengine.com/job/pr-pipeline/13945/ Packages: http://buildcache.cfengine.com/packages/testing-pr/jenkins-pr-pipeline-13945/ |
Contributor
|
Thanks nice addition!! Much needed |
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Summary
Adds a
cancelattribute toclassespromises so policy can undefine aclass. Until now a classes promise could only define a class; the only way
to undefine one from policy was a
cancel_*classes body attached to anotherpromise's outcome. With
cancel, the classes promise can undefine its ownpromiser directly:
When the cancel expression (a class expression — string or a function
returning a boolean) evaluates true, the promiser class is undefined if it is
currently defined. False trigger, or an already-undefined class, is a no-op.
Key detail: the class-skipping exception
ExpandDeRefPromise()normally excludes a classes promise whose promiser isalready defined (an optimization). A
cancelpromise must run precisely inthat case, so the skip now makes an exception when the
cancelattribute ispresent. This is the crux of the change — without it the promise would never
actuate.
Behaviour
expression,and,or,xor,not,dist,select_class) via the existing "Irreconcilableconstraints" check —
cancelis counted like any other class-body attribute.consistent with the
cancel_*classes body attributes (ENT-7718 / CFE-3647).cancel_*classes body(
DeleteAllClasses): persistent removal +EvalContextClassRemove+bundle-frame removal.
Tests
New acceptance tests in
tests/acceptance/02_classes/01_basic/:cancel_attribute.cf,cancel_attribute_hardclass.cf,cancel_attribute_mutex.cf(+.sub).Full
02_classessuite: 117 passed, 0 failed (3 staging-skipped, 3pre-existing soft failures).
Docs
Documentation PR: cfengine/documentation (CFE-4686) adds the
cancelreferencesection.
Ticket: https://northerntech.atlassian.net/browse/CFE-4686
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