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

The response content key can be a specific media type (e.g. application/json) or a wildcard media type range (e.g. image/*). Media type definitions must be in compliance with RFC6838.

Maximum SeverityWarning
MessageThe key of the response body content definition is invalid.
Rule SystemSyntax
Broad CategoryResponses
Products ImpactedAPI Transformer, Code Generation, Developer Experience Portal
Tagsopenapi3 openapi syntax linting media type content body response

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.
  • Media type ranges use the asterisk '' character to group media types into ranges, with '/' indicating all media types and 'type/' indicating all subtypes of that type. The media-range can include media type parameters that are applicable to that range. Each media-range might be followed by zero or more applicable media type parameters (e.g., charset).
  • Some examples of media type ranges include /, text/. Here text/ media type range is more specific than / and has more precedence.

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