[APIM] AsFormUrlEncodedContent policy expression

Author: dlepow

articles/api-management/api-management-policy-expressions.md

@@ -7,7 +7,7 @@ author: dlepow
 
 ms.service: api-management
 ms.topic: article
-ms.date: 02/07/2022
+ms.date: 12/08/2022
 ms.author: danlep
 ---
 # API Management policy expressions
@@ -213,7 +213,7 @@ The `context` variable is implicitly available in every policy [expression](api-
 |<a id="ref-context-user"></a>`context.User`|`Email`: `string`<br /><br /> `FirstName`: `string`<br /><br /> `Groups`: `IEnumerable<`[`IGroup`](#ref-igroup)`>`<br /><br /> `Id`: `string`<br /><br /> `Identities`: `IEnumerable<`[`IUserIdentity`](#ref-iuseridentity)`>`<br /><br /> `LastName`: `string`<br /><br /> `Note`: `string`<br /><br /> `RegistrationDate`: `DateTime`|
 |<a id="ref-iapi"></a>`IApi`|`Id`: `string`<br /><br /> `Name`: `string`<br /><br /> `Path`: `string`<br /><br /> `Protocols`: `IEnumerable<string>`<br /><br /> `ServiceUrl`: [`IUrl`](#ref-iurl)<br /><br /> `SubscriptionKeyParameterNames`: [`ISubscriptionKeyParameterNames`](#ref-isubscriptionkeyparameternames)|
 |<a id="ref-igroup"></a>`IGroup`|`Id`: `string`<br /><br /> `Name`: `string`|
-|<a id="ref-imessagebody"></a>`IMessageBody`|`As<T>(preserveContent: bool = false): Where T: string, byte[],JObject, JToken, JArray, XNode, XElement, XDocument`<br /><br /> The `context.Request.Body.As<T>` and `context.Response.Body.As<T>` methods are used to read either a request and response message body in specified type `T`. By default, the method:<br /><ul><li>Uses the original message body stream.</li><li>Renders it unavailable after it returns.</li></ul> <br />To avoid that and have the method operate on a copy of the body stream, set the `preserveContent` parameter to `true`, as in [this example](api-management-transformation-policies.md#SetBody).|
+|<a id="ref-imessagebody"></a>`IMessageBody`|`As<T>(bool preserveContent = false): Where T: string, byte[], JObject, JToken, JArray, XNode, XElement, XDocument` <br /><br /> - The `context.Request.Body.As<T>` and `context.Response.Body.As<T>` methods read a request or response message body in specified type `T`. <br/><br/> - Or - <br/><br/>`AsFormUrlEncodedContent(bool preserveContent = false)` <br/></br>- The `context.Request.Body.AsFormUrlEncodedContent()` and `context.Response.Body.AsFormUrlEncodedContent()` methods read URL-encoded form data in a request or response message body and return an  `IDictionary<string, IList<string>>` object. The decoded object supports `IDictionary` operations and the following expressions: `ToQueryString()`, `JsonConvert.SerializeObject()`, `ToFormUrlEncodedContent().` <br/><br/> By default, the `As<T>` and `AsFormUrlEncodedContent()` methods:<br /><ul><li>Use the original message body stream.</li><li>Render it unavailable after it returns.</li></ul> <br />To avoid that and have the method operate on a copy of the body stream, set the `preserveContent` parameter to `true`, as in [this example](api-management-transformation-policies.md#SetBody).|
 |<a id="ref-iprivateendpointconnection"></a>`IPrivateEndpointConnection`|`Name`: `string`<br /><br /> `GroupId`: `string`<br /><br /> `MemberName`: `string`<br /><br />For more information, see the [REST API](/rest/api/apimanagement/current-ga/private-endpoint-connection/list-private-link-resources).|
 |<a id="ref-iurl"></a>`IUrl`|`Host`: `string`<br /><br /> `Path`: `string`<br /><br /> `Port`: `int`<br /><br /> [`Query`](#ref-iurl-query): `IReadOnlyDictionary<string, string[]>`<br /><br /> `QueryString`: `string`<br /><br /> `Scheme`: `string`|
 |<a id="ref-iuseridentity"></a>`IUserIdentity`|`Id`: `string`<br /><br /> `Provider`: `string`|

articles/api-management/api-management-transformation-policies.md

@@ -346,7 +346,7 @@ In this example the policy routes the request to a service fabric backend, using
 >   -   Preserving the content of a request in the outbound pipeline doesn't make sense because the request has already been sent to the backend at this point.
 >   -   If this policy is used when there is no message body, for example in an inbound GET, an exception is thrown.
 
- For more information, see the `context.Request.Body`, `context.Response.Body`, and the `IMessage` sections in the [Context variable](api-management-policy-expressions.md#ContextVariables) table.
+ For more information, see the `context.Request.Body`, `context.Response.Body`, and the `IMessageBody` sections in the [Context variable](api-management-policy-expressions.md#ContextVariables) table.
 
 [!INCLUDE [api-management-policy-generic-alert](../../includes/api-management-policy-generic-alert.md)]
 
@@ -399,6 +399,19 @@ Since we are not reserving the original request body, accessing it later in the
 
 ```
 
+#### Example accessng the body as URL-encoded form data
+The following example uses the `AsFormUrlEncodedContent()` expression to access the request body as URL-encoded form data (`application/x-www-form-urlencoded`), and then converts it to JSON. Since we are not reserving the original request body, accessing it later in the pipeline will result in an exception.
+
+```xml
+<set-body> 
+@{ 
+    var inBody = context.Request.Body.AsFormUrlEncodedContent();
+    return JsonConvert.SerializeObject(inBody); 
+} 
+</set-body>
+
+```
+
 #### Filter response based on product
  This example shows how to perform content filtering by removing data elements from the response received from a backend service when using the `Starter` product. The example backend response includes root-level properties similar to the [OpenWeather One Call API](https://openweathermap.org/api/one-call-api).