feat: Add support for XPath and versions of XPath and JSON Path for C…

…riterion expressions (#172)

versions/1.0.0.md

@@ -474,7 +474,7 @@ stepId: joinWaitingListStep
 criteria:
     # assertions to determine if this success action should be executed
     - context: $response.body
-      condition: $.Pets.length() > 0
+      condition: $[?count(@.pets) > 0]
       type: JSONPath
 ```
 
@@ -704,7 +704,7 @@ Field Name | Type | Description
 ---|:---:|---
 <a name="criterionContext"></a>context | `{expression}` | A [runtime expression](#runtime-expressions) used to set the context for the condition to be applied on. If `type` is specified, then the `context` MUST be provided (e.g. `$response.body` would set the context that a JSONPath query expression could be applied to).
 <a name="criterionCondition"></a>condition | `string` | **REQUIRED**. The condition to apply. Conditions can be simple (e.g. `$statusCode == 200` which applies a operator on a value obtained from a runtime expression), or a regex, or a JSONPath expression. For regex and [JSONPath](https://datatracker.ietf.org/doc/draft-ietf-jsonpath-base/21/), the `type` and `context` MUST be specified.
-<a name="criterionType"></a>type | `string` | The type of condition to be applied. If specified, the options allowed are `simple`, `regex` or `JSONPath`. If omitted, then the condition is assumed to be `simple`, which at most combines literals, operators and [Runtime Expressions](#runtime-expressions).
+<a name="criterionType"></a>type | `string` \| [Criterion Expression Type Object](#criterion-expression-type-object) | The type of condition to be applied. If specified, the options allowed are `simple`, `regex`, `jsonpath` or `xpath`. If omitted, then the condition is assumed to be `simple`, which at most combines literals, operators and [Runtime Expressions](#runtime-expressions). If `jsonpath`, then the expression MUST conform to [JSON Path](https://www.rfc-editor.org/rfc/rfc9535.html). If `xpath` the expression MUST conform to [XML Path Language 3.1](https://www.w3.org/TR/xpath-31/#d2e24229). Should other variants of JSON Path or XPath be required, then a [Criterion Expression Type Object](#criterion-expression-type-object) MUST be specified.
 
 
 This object MAY be extended with [Specification Extensions](#specificationExtensions).
@@ -727,8 +727,38 @@ This object MAY be extended with [Specification Extensions](#specificationExtens
 **JSONPath Condition Example**
 ```yaml
 - context: $response.body
-  condition: $[?length(@.pets) > 0]
-  type: JSONPath
+  condition: $[?count(@.pets) > 0]
+  type: jsonpath
+```
+
+#### Criterion Expression Type Object
+
+An object used to describe the type and version of an expression used within a [Criterion Object](#criterion-object). If this object is not defined, then the following defaults apply:
+ - JSON Path as described by [RFC 9535](https://www.rfc-editor.org/rfc/rfc9535.html)
+ - XPath as described by [XML Path Language 3.1](https://www.w3.org/TR/xpath-31)
+
+Defining this object gives the ability to utilize tooling  compatible with older versions of either JSON Path or XPath.
+
+ ##### Fixed Fields
+Field Name | Type | Description
+---|:---:|---
+<a name="criterionExpressionType"></a>type | `string` | **REQUIRED**. The type of condition to be applied. The options allowed are `jsonpath` or `xpath`. 
+<a name="criterionExpressionVersion"></a>version | `string` | **REQUIRED**. A short hand string representing the version of the expression type being used. The allowed values for JSON Path are `draft-goessner-dispatch-jsonpath-00`. The allowed values for XPath are `xpath-30`, `xpath-20`, or `xpath-10`.
+
+This object MAY be extended with [Specification Extensions](#specificationExtensions).
+
+##### Criterion Expression Type Example
+
+**JSON Path Example**
+```yaml
+  type: jsonpath
+  version: draft-goessner-dispatch-jsonpath-00
+```
+
+**XPath Example**
+```yaml
+  type: xpath
+  version: xpath-30
 ```
 
 #### Request Body Object