Add api ref for create of attributes

Change-Id: I6fe61a13a3fb0b99f5400b9cf50c10b9cf10a66e

api-ref/source/attributes.inc

@@ -4,7 +4,7 @@
 Attributes
 ++++++++++
 
-Lists, shows details for attributes.
+Lists, shows details, creates for attributes.
 
 A `attribute` represents the trait of a physical card like FPGA or GPU.
 
@@ -79,3 +79,26 @@ Response
 
 .. literalinclude:: ../../doc/api_samples/attributes/attributes-getone-resp.json
    :language: javascript
+
+Create Attributes
+-----------------
+
+.. rest_method:: POST /v2/attributes
+
+Creates an attribute. The payload should have the following field:
+
+Request
+=======
+.. rest_parameters:: parameters.yaml
+
+  - deployable_id: attribute_deployable_id_req
+  - key: attribute_key_req
+  - value: attribute_value_req
+
+**Example post curl**
+
+.. literalinclude:: ../../doc/api_samples/attributes/attributes-post-curl.json
+
+**Example response: create an attribute**
+
+.. literalinclude:: ../../doc/api_samples/attributes/attributes-create-resp.json

api-ref/source/parameters.yaml

@@ -79,6 +79,12 @@ hostname:
   type: string
 
 # variables in body
+attribute_deployable_id_req:
+  description: |
+    ID of deployable associated with the attribute.
+  in: body
+  required: true
+  type: integer
 attribute_deployable_id_resp:
   description: |
     ID of deployable associated with the attribute.
@@ -91,6 +97,12 @@ attribute_id_resp:
   in: body
   required: true
   type: integer
+attribute_key_req:
+  description: |
+    The key of the attribute.
+  in: body
+  required: true
+  type: string
 attribute_key_resp:
   description: |
     The key of the attribute.
@@ -103,6 +115,12 @@ attribute_uuid_resp:
   in: body
   required: true
   type: string
+attribute_value_req:
+  description: |
+    The value of the attribute.
+  in: body
+  required: true
+  type: string
 attribute_value_resp:
   description: |
     The value of the attribute.