api-ref: Correcting Network v2.0 API extensions

This patch corrects Network v2.0 API extensions:
- Change 'extensions' type from 'object' to 'array'
- Change '{alias}' parameter from 'in:body' to 'in:path'
Refactor code

Change-Id: I2e64669224ab4a970c17cc192abdf08519b1576f
Partially-Implements: blueprint neutron-in-tree-api-ref

api-ref/source/v2/extensions.inc

@@ -1,15 +1,12 @@
 .. -*- rst -*-
-.. needs:method_verification
-.. needs:parameter_verification
-.. needs:example_verification
-.. needs:body_verification
 
 ==========
 Extensions
 ==========
 
-Lists available Networking API v2.0 extensions and shows details
-for an extension.
+
+Extensions introduce features and vendor-specific functionality to
+the API.
 
 List extensions
 ===============
@@ -18,15 +15,12 @@ List extensions
 
 Lists available extensions.
 
-Extensions introduce features and vendor-specific functionality to
-the API.
-
-The response shows the extension name and its alias. To show
-details for an extension, you specify the alias.
+Lists available Networking API v2.0 extensions and shows details
+for an extension.
 
 Normal response codes: 200
 
-Error response codes: 203
+Error response codes: 401
 
 Request
 -------
@@ -36,12 +30,12 @@ Response Parameters
 
 .. rest_parameters:: parameters.yaml
 
-   - updated: updated
-   - description: description
-   - links: links
-   - alias: alias
    - extensions: extensions
-   - name: name
+   - name: extension-name
+   - links: extension-links
+   - alias: extension-alias-body
+   - updated: extension-updated
+   - description: extension-description
 
 Response Example
 ----------------
@@ -55,29 +49,31 @@ Show extension details
 .. rest_method::  GET /v2.0/extensions/{alias}
 
 Shows details for an extension, by alias.
+The response shows the extension name and its alias. To show
+details for an extension, you specify the alias.
 
 Normal response codes: 200
 
-Error response codes: 203
+Error response codes: 401, 404
 
 Request
 -------
 
 .. rest_parameters:: parameters.yaml
 
-   - alias: alias
+   - alias: extensions-alias-path
 
 Response Parameters
 -------------------
 
 .. rest_parameters:: parameters.yaml
 
-   - updated: updated
-   - description: description
-   - links: links
-   - alias: alias
    - extension: extension
-   - name: name
+   - name: extension-name
+   - links: extension-links
+   - alias: extension-alias-body
+   - updated: extension-updated
+   - description: extension-description
 
 Response Example
 ----------------

api-ref/source/v2/parameters.yaml

@@ -1,12 +1,6 @@
 # variables in header
 
 # variables in path
-alias_1:
-  description: |
-    The alias of an extension.
-  in: path
-  required: false
-  type: string
 connection_id:
   description: |
     The UUID of the IPSec site-to-site connection.
@@ -19,6 +13,12 @@ endpoint_group_id:
   in: path
   required: false
   type: string
+extensions-alias-path:
+  description: |
+    The alias of an extension.
+  in: path
+  required: true
+  type: string
 firewall_id:
   description: |
     The UUID of the firewall.
@@ -1297,12 +1297,44 @@ extension:
   in: body
   required: true
   type: object
+extension-alias-body:
+  description: |
+    The alias for the extension. For example "quotas" or
+    "security-group".
+  in: body
+  required: true
+  type: string
+extension-description:
+  description: |
+    The human-readable description for the resource.
+  in: body
+  required: true
+  type: string
+extension-links:
+  description: |
+     List of links related to the extension.
+  in: body
+  required: true
+  type: array
+extension-name:
+  description: |
+    Human-readable name of the resource.
+  in: body
+  required: true
+  type: string
+extension-updated:
+  description: |
+    The date and timestamp when the extension was
+    last updated.
+  in: body
+  required: true
+  type: string
 extensions:
   description: |
     A list of ``extension`` objects.
   in: body
   required: true
-  type: object
+  type: array
 external_v4_ip:
   description: |
     Read-only external (public) IPv4 address that is