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This rule belongs to the openapi-v3-standards-validation ruleset and states that:

The discriminator is the name of the property that decides which schema definition validates the structure of the model. This field must be marked as a required schema field.

Maximum SeverityError
MessageDiscriminator field is marked as optional.
Rule SystemSemantic
Broad CategorySchemas
Products ImpactedAPI Transformer, Code Generation, Developer Experience Portal
Tagsopenapi3 openapi standards semantic validation discriminator property field schema

Suggested Fixes

  • Ensure that name of the schema property, which is marked as a discriminator, is also included in the schema's required list.
  • If the schema property should not be a required property, it should not be marked as a discriminator.
  • Name of the property marked as discriminator is compared with the schema property name in a case-sensitive manner.

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