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

Use of contentMediaType without contentEncoding is not recommended for multipart property definitions. Per the JSON Schema specification, contentMediaType without contentEncoding present is treated as if contentEncoding: identity were present. While useful for embedding text documents such as text/html into JSON strings, it is not useful for a multipart/form-data part, as it just causes the document to be treated as text/plain instead of its actual media type.

Maximum SeverityWarning
MessageMultipart property uses contentMediaType without contentEncoding.
Rule SystemSemantic
Broad CategoryMedia Types
Products ImpactedAPI Transformer, Code Generation, Developer Experience Portal
Tagsopenapi3 openapi standards semantic linting contentMediaType contentEncoding content media type multipart schema property

Suggested Fixes

  • If the content will be encoded, use contentEncoding to specify related information.
  • Remove contentMediaType from the property schema definition if contentEncoding is not expected to be added.

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