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

Media type of string content can be defined using the contentMediaType property of a Schema Object which must be in compliance with RFC2046.

Maximum SeverityError
MessageValue of property contentMediaType in Schema Object is invalid.
Rule SystemSyntax
Broad CategorySchemas
Products ImpactedAPI Transformer, Code Generation, Developer Experience Portal
Tagsopenapi3 openapi syntax validation media type content string json schema schema

Suggested Fixes

  • A media type consists of a top-level type and a subtype, which is further structured into a tree. A media type can optionally define a suffix and parameters as well.
  • A media type follows a pattern like the following where segments between [] are optional segments: <type>/[<tree>.]<subtype>[+<suffix>]*[;<parameter>]
  • Some examples of valid media types are: application/json, application/vnd.api+json, text/plain.
  • Some common top-level types include the following: text, image, audio, video, application, multipart, message.

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