# standard-media-types

Source: https://apigenie.pl/docs/linter/swagger/rules/standard-media-types

This rule checks whether a Swagger 2.0 document uses only well-known media
types.

## Rule Details

Non-standard or misspelled media types lead to interoperability issues:
clients and servers may fail to negotiate the format of requests and
responses.

The `standard-media-types` rule checks:

- the root `consumes` and `produces` lists,
- the `consumes` and `produces` lists of every operation,
- the media type keys of the `examples` of every response (response
  references are skipped).

It reports `Non-standard media type is used (<media type>)` for every value
that is not on the built-in list of well-known media types, such as
`application/json`, `application/xml`, `application/x-www-form-urlencoded`,
`multipart/form-data`, `text/plain` or `application/octet-stream`. Wildcards
(`*/*`, `application/*`) are accepted, and parameters after `;` (like
`charset=utf-8`) are ignored. Values without a subtype, like `json`, are
reported.

## Configuration

None.

## Examples

**Good**.

```yaml
swagger: '2.0'
info:
  title: Pet Store
  version: 1.0.0
consumes: [application/json]
produces: [application/json, application/xml]
paths:
  /pets:
    get:
      produces: [text/plain]
      responses:
        '200':
          description: The list of pets.
          examples:
            text/plain: Rex, Fluffy
```

**Bad**. `application/x-custom` and `text/foo` are not well-known media
types, and `json` has no subtype.

```yaml
swagger: '2.0'
info:
  title: Pet Store
  version: 1.0.0
consumes: [application/x-custom]
paths:
  /pets:
    get:
      produces: [json]
      responses:
        '200':
          description: The list of pets.
          examples:
            text/foo: Rex
```

## When Not to Use It

You may disable this rule if your API deliberately uses vendor-specific media
types that are not on the built-in list.

## Compatibility

This rule is compatible with Swagger 2.0 documents. OpenAPI 3.x and AsyncAPI
documents are linted by the OpenAPI and AsyncAPI linters, which have their own
`standard-media-types` rules.