Syntax      = { Production } .
Production  = production_name "=" [ Expression ] "." .
Expression  = Term { "|" Term } .
Term        = Factor { Factor } .
Factor      = production_name | token [ "…" token ] | Group | Option | Repetition .
Group       = "(" Expression ")" .
Option      = "[" Expression "]" .
Repetition  = "{" Expression "}" .
</pre>

<p>
Productions are expressions constructed from terms and the following

  // the affinity expressions specified by this field, but it may choose
  // a node that violates one or more of the expressions. The node that is
  // most preferred is the one with the greatest sum of weights, i.e.
  // for each node that meets all of the scheduling requirements (resource
  // request, requiredDuringScheduling affinity expressions, etc.),

- Improved handling of jsonpath expressions for `kubectl wait --for`. It is now possible to use simple filter expressions which match on a field's content. ([#118748](https://github.com/kubernetes/kubernetes/pull/118748), [@andreaskaris](https://github.com/andreaskaris))

- The "value" part in the `wait --for=jsonpath='{expression}'[=value]` is now
  optional. If the value is not provided i.e., the command looks like `wait --for=jsonpath='{expression}'`
  then the wait condition is interpreted as matched when the expression returns

- Added authorization check support to the CEL expressions of ValidatingAdmissionPolicy via a `authorizer`

#### Fixes

- [`KT-60387`](https://youtrack.jetbrains.com/issue/KT-60387) K2: IDE K2: "org.jetbrains.kotlin.fir.expressions.impl.FirArgumentListImpl cannot be cast to class org.jetbrains.kotlin.fir.expressions.impl.FirResolvedArgumentList"
- [`KT-61228`](https://youtrack.jetbrains.com/issue/KT-61228) False positive MUST_BE_INITIALIZED_OR_FINAL_OR_ABSTRACT_WARNING for effectively final properties

## Changelog since v1.26.8

## Changes by Kind

### API Change

- Fixed a bug where CEL expressions in CRD validation rules would incorrectly compute a high estimated cost for functions that return strings, lists or maps.

* The parameter `regex` has been deprecated and replaced by `pattern`.
    * You can read more about it in the docs for [Query Parameters and String Validations: Add regular expressions](https://fastapi.tiangolo.com/tutorial/query-params-str-validations/#add-regular-expressions).
* New Pydantic models use an improved and simplified attribute `model_config` that takes a simple dict instead of an internal class `Config` for their configuration.

- CEL CRD validation expressions may now reference existing object state using the identifier `oldSelf`. ([#108073](https://github.com/kubernetes/kubernetes/pull/108073), [@benluddy](https://github.com/benluddy))

### Promoted CRD Validation Expression Language to Beta