MXS-1220: Add support for PATCH

The PATCH method should now be used instead the PUT method to update
resources.  As PUT request bodies should represent complete resources, the
use of PUT to update resources is no longer supported.

Altered tests to use PATCH instead of PUT for updating resources.

Documentation/REST-API/API.md

@@ -111,10 +111,16 @@ Credentials for authentication.
 #### Content-Type
 
 All PUT and POST requests must use the `Content-Type: application/json` media
-type and the request body must be a valid JSON representation of a resource. All
-PATCH requests must use the `Content-Type: application/json` media type and the
-request body must be a JSON document containing a partial definition of the
-original resource.
+type and the request body must be a complete and valid JSON representation of a
+resource. All PATCH requests must use the `Content-Type: application/json` media
+type and the request body must be a JSON document containing a partial
+definition of the original resource.
+
+The current version of the API supports PATCH-like PUT requests with
+partial definitions of resources in the request body. This is discouraged
+as it goes against the intended use of the PUT method. Future versions of
+the MaxScale REST API can remove this support which means that this
+functionality is deprecated.
 
 #### Host
 

Documentation/REST-API/Resources-Monitor.md

@@ -267,7 +267,7 @@ The :name in the URI must map to a monitor name with all whitespace replaced wit
 hyphens. The request body must be a valid JSON document representing the modified monitor.
 
 ```
-PUT /v1/monitor/:name
+PATCH /v1/monitor/:name
 ```
 
 ### Modifiable Fields

Documentation/REST-API/Resources-Server.md

@@ -312,7 +312,7 @@ Status: 403 Forbidden
 ### Update a server
 
 ```
-PUT /v1/servers/:name
+PATCH /v1/servers/:name
 ```
 
 The _:name_ in the URI must map to a server name with all whitespace replaced
@@ -443,12 +443,12 @@ Request for `PUT /v1/server/server1`:
 }
 ```
 
-The current implementation accepts both PUT and PATCH requests with partially
-defined resources as request body. If parts of the resource are not defined
-(e.g. the `attributes` field in the above example), those parts of the resource
-are not modified. All parts that are defined are interpreted as the new
-definition of those part of the resource. In the above example, the
-`relationships` of the resource are completely redefined.
+The current implementation accepts PATCH requests with partially defined
+resources as request body. If parts of the resource are not defined (e.g. the
+`attributes` field in the above example), those parts of the resource are not
+modified. All parts that are defined are interpreted as the new definition of
+those part of the resource. In the above example, the `relationships` of the
+resource are completely redefined.
 
 #### Response
 

Documentation/REST-API/Resources-Service.md

@@ -265,7 +265,7 @@ The _:name_ in the URI must map to a service name and the request body must be a
 valid JSON Patch document which is applied to the resource.
 
 ```
-PUT /v1/services/:name
+PATCH /v1/services/:name
 ```
 
 The following standard service parameters can be modified.