diff --git a/docs/design/selector-generation.md b/docs/design/selector-generation.md index 545de9cf309..3ada304c8b1 100644 --- a/docs/design/selector-generation.md +++ b/docs/design/selector-generation.md @@ -27,7 +27,7 @@ Documentation for other releases can be found at -Proposed Design +Design ============= # Goals @@ -110,18 +110,39 @@ No changes ## Kubectl No required changes. -Suggest moving SELECTOR to wide output of `kubectl get jobs` since users don't write the selector. +Suggest moving SELECTOR to wide output of `kubectl get jobs` since users do not write the selector. ## Docs Remove examples that use selector and remove labels from pod templates. Recommend `kubectl get jobs -l job-name=name` as the way to find pods of a job. -# Cross Version Compat +# Conversion -`v1beta1` will not have a `job.spec.manualSelector` and will not provide a default selector. +The following applies to Job, as well as to other types that adopt this pattern. -Conversion from v1beta1 to v1 will use the user-provided selector and set `job.spec.manualSelector=true`. +- Type `extensions/v1beta1` gets a field called `job.spec.autoSelector`. +- Both the internal type and the `batch/v1` type will get `job.spec.manualSelector`. +- The fields `manualSelector` and `autoSelector` have opposite meanings. +- Each field defaults to false when unset, and so v1beta1 has a different default than v1 and internal. This is intentional: we want new + uses to default to the less error-prone behavior, and we do not want to change the behavior + of v1beta1. + +*Note*: since the internal default is changing, client +library consumers that create Jobs may need to add "job.spec.manualSelector=true" to keep working, or switch +to auto selectors. + +Conversion is as follows: +- `extensions/__internal` to `extensions/v1beta1`: the value of `__internal.Spec.ManualSelector` is defaulted to false if nil, negated, defaulted to nil if false, and written `v1beta1.Spec.AutoSelector`. +- `extensions/v1beta1` to `extensions/__internal`: the value of `v1beta1.SpecAutoSelector` is defaulted to false if nil, negated, defaulted to nil if false, and written to `__internal.Spec.ManualSelector`. + +This conversion gives the following properties. + +1. Users that previously used v1beta1 do not start seeing a new field when they get back objects. +2. Distinction between originally unset versus explicitly set to false is not preserved (would have been nice to do so, but requires more complicated + solution). +3. Users who only created v1beta1 examples or v1 examples, will not ever see the existence of either field. +4. Since v1beta1 are convertable to/from v1, the storage location (path in etcd) does not need to change, allowing scriptable rollforward/rollback. # Future Work