request-property-discriminator-mapping-changed

What this check detects

A `discriminator` tells tooling which subschema of a `oneOf` or `anyOf` a payload belongs to, by looking at one property. Its `mapping` connects each value of that property to a schema.

Changing a mapping entry repoints a value at a different schema. oasdiff reports it as informational because the discriminator is a resolution hint, not the validation itself: what a request must look like is still decided by the `oneOf` / `anyOf` branches. It is worth reviewing though, since generated clients use the mapping to choose a type, so a remap can change which model a payload deserializes into.

Example

A request with "petType": "cat" now resolves to Dog. The oneOf branches still decide what validates, but a generated client picks a different model.

Change its severity

oasdiff reports request-property-discriminator-mapping-changed as informational, so it does not fail CI. To treat it as a warning or an error under your own compatibility policy, or to turn it off, set its level in a severity-levels file:

Put one rule per line; the level can be err, warn, or info, or none to disable the check entirely:

# severity.txt
request-property-discriminator-mapping-changed err

Then pass it to oasdiff:

oasdiff changelog base.yaml revision.yaml --severity-levels severity.txt