Split up Encoding fields like Param/Header

This splits the Encoding Object's fixed fields table
to make the usage more clear, and closer to how it is presented
for the Parameter and Header Objects

Author: handrews

versions/3.0.4.md

@@ -1621,14 +1621,14 @@ A single encoding definition applied to a single schema property; encodings are
 Properties are correlated with `multipart` parts using the `name` parameter to `Content-Disposition: form-data`, and with `application/x-www-form-urlencoded` using the query string paramter names.
 In both cases, their order is implementation-defined.
 
-##### Fixed Fields
+###### Common Fixed Fields
+
+These fields MAY be used either with or without the RFC6570-style serialization fields defined in the next section below.
+
 Field Name | Type | Description
 ---|:---:|---
 <a name="encodingContentType"></a>contentType | `string` | The `Content-Type` for encoding a specific property. The value is a comma-separated list, each element of which is either a specific media type (e.g. `image/png`) or a wildcard media type (e.g. `image/*`). Default value depends on the property type as shown in the table below.
 <a name="encodingHeaders"></a>headers | Map[`string`, [Header Object](#headerObject) \| [Reference Object](#referenceObject)] | A map allowing additional information to be provided as headers. `Content-Type` is described separately and SHALL be ignored in this section. This property SHALL be ignored if the request body media type is not a `multipart`.
-<a name="encodingStyle"></a>style | `string` | Describes how a specific property value will be serialized depending on its type.  See [Parameter Object](#parameterObject) for details on the [`style`](#parameterStyle) property. The behavior follows the same values as `query` parameters, including default values. This property SHALL be ignored if the request body media type is not `application/x-www-form-urlencoded`.
-<a name="encodingExplode"></a>explode | `boolean` | When this is true, property values of type `array` or `object` generate separate parameters for each value of the array, or key-value-pair of the map.  For other types of properties this property has no effect. When [`style`](#encodingStyle) is `form`, the default value is `true`. For all other styles, the default value is `false`. This property SHALL be ignored if the request body media type is not `application/x-www-form-urlencoded`.
-<a name="encodingAllowReserved"></a>allowReserved | `boolean` | When this is true, parameter values are serialized  using reserved expansion, as defined by [RFC6570](https://datatracker.ietf.org/doc/html/rfc6570#autoid-20), which allows [RFC3986's reserved character set](https://datatracker.ietf.org/doc/html/rfc3986#autoid-13), as well as percent-encoded triples, to pass through unchanged, while still percent-encoding all other disallowed characters (including `%` outside of percent-encoded triples). Applications are still responsible for percent-encoding reserved characters that are [not allowed in the query string](https://datatracker.ietf.org/doc/html/rfc3986#autoid-24) (`[`, `]`, `#`), or have a special meaning in `application/x-www-form-urlencoded` (`-`, `&`, `+`); see Appendices [C](#usingRFC6570Implementations) and [E](#percentEncodingAndFormMediaTypes) for details. This property only applies to parameters with an `in` value of `query`. The default value is `false`.
 
 This object MAY be extended with [Specification Extensions](#specificationExtensions).
 
@@ -1641,8 +1641,29 @@ Property Type | Property Format | Default `contentType`
 `object` | _n/a_ | `application/json`
 `array` | _n/a_ | according to the `type` and `format` of the `items` schema
 
+##### Fixed Fields for RFC6570-style Serialization
+
+Field Name | Type | Description
+---|:---:|---
+<a name="encodingStyle"></a>style | `string` | Describes how a specific property value will be serialized depending on its type.  See [Parameter Object](#parameterObject) for details on the [`style`](#parameterStyle) property. The behavior follows the same values as `query` parameters, including default values. This property SHALL be ignored if the request body media type is not `application/x-www-form-urlencoded`.
+<a name="encodingExplode"></a>explode | `boolean` | When this is true, property values of type `array` or `object` generate separate parameters for each value of the array, or key-value-pair of the map.  For other types of properties this property has no effect. When [`style`](#encodingStyle) is `form`, the default value is `true`. For all other styles, the default value is `false`. This property SHALL be ignored if the request body media type is not `application/x-www-form-urlencoded`.
+<a name="encodingAllowReserved"></a>allowReserved | `boolean` | When this is true, parameter values are serialized  using reserved expansion, as defined by [RFC6570](https://datatracker.ietf.org/doc/html/rfc6570#autoid-20), which allows [RFC3986's reserved character set](https://datatracker.ietf.org/doc/html/rfc3986#autoid-13), as well as percent-encoded triples, to pass through unchanged, while still percent-encoding all other disallowed characters (including `%` outside of percent-encoded triples). Applications are still responsible for percent-encoding reserved characters that are [not allowed in the query string](https://datatracker.ietf.org/doc/html/rfc3986#autoid-24) (`[`, `]`, `#`), or have a special meaning in `application/x-www-form-urlencoded` (`-`, `&`, `+`); see Appendices [C](#usingRFC6570Implementations) and [E](#percentEncodingAndFormMediaTypes) for details. This property only applies to parameters with an `in` value of `query`. The default value is `false`.
+
 See also [Appendix C: Using RFC6570 Implementations](#usingRFC6570Implementations) for additional guidance.
 
+The role of `contentType` with `application/x-www-form-urlencoded` request bodies was not described in detail in version 3.0.3 and earlier of this specification.
+To match the intent of these fields and be compatible with version 3.1 of this specification, it is RECOMMENDED that whenever any of `style`, `explode`, or `allowReserved` are present with an explicit value:
+
+* The value of `contentType`, whether it is explicitly defined or has the default value, is to be ignored
+* If any of `style`, `explode`, or `allowReserved` are _not_ present with explicit values, then they are to be treated as if they were present with their default values
+
+However, if all three of `style`, `explode`, and `allowReserved` fields are absent, it is RECOMMENDED that:
+
+* All three keywords are to be entirely ignored, rather than treated as having their default values
+* Encoding is to be based on `contentType` alone, whether it is present with an explicit value or absent and treated as having its default value
+
+This makes the presence of at least one of `style`, `explode`, or `allowReserved` with an explicit value equivalent to using `schema` with `in: query` Parameter Objects, and their absence the equivalent of using `content`, but with the media type specified in `contentType` rather than through a Media Type Object.
+
 ###### Encoding `multipart` Media Types
 
 Properties are correlated with `multipart` parts using the `name` parameter to `Content-Disposition: form-data`, and their order is implementation-defined.
@@ -1660,21 +1681,6 @@ Note also that `Content-Transfer-Encoding` is deprecated for `multipart/form-dat
 Using `format: byte` for a multipart field is equivalent to setting `Content-Transfer-Encoding: base64`.
 If `format: byte` is used along with setting a different `Content-Transfer-Encoding` value with the `headers` field, the result is undefined.
 
-###### Encoding the `application/x-www-form-urlencoded` Media Type
-
-The role of `contentType` with `application/x-www-form-urlencoded` request bodies was not described in detail in version 3.0.3 and earlier of this specification.
-To match the intent of these fields and be compatible with version 3.1 of this specification, it is RECOMMENDED that whenever any of `style`, `explode`, or `allowReserved` are present with an explicit value:
-
-* The value of `contentType`, whether it is explicitly defined or has the default value, is to be ignored
-* If any of `style`, `explode`, or `allowReserved` are _not_ present with explicit values, then they are to be treated as if they were present with their default values
-
-However, if all three of `style`, `explode`, and `allowReserved` fields are absent, it is RECOMMENDED that:
-
-* All three keywords are to be entirely ignored, rather than treated as having their default values
-* Encoding is to be based on `contentType` alone, whether it is present with an explicit value or absent and treated as having its default value
-
-This makes the presence of at least one of `style`, `explode`, or `allowReserved` with an explicit value equivalent to using `schema` with `in: query` Parameter Objects, and their absence the equivalent of using `content`, but with the media type specified in `contentType` rather than through a Media Type Object.
-
 ##### Encoding Object Example
 
 `multipart/form-data` allows for binary parts: