api-guide: flesh out flavor extra specs and image properties

This adds high level details and links to more detailed docs
in both nova and glance.

This also un-hides the document so it shows up in the table of
contents on the main page. Previously it was being linked from
the general info page and some typos in there are fixed as well.

Change-Id: I495b9ae7855d36cb2597272bcae7ec00360bbed4

api-guide/source/conf.py

@@ -285,6 +285,7 @@ pdf_documents = [
 # -- Options for openstackdocstheme -------------------------------------------
 
 openstack_projects = [
+    'glance',
     'nova',
     'neutron',
     'placement',

api-guide/source/extra_specs_and_properties.rst

@@ -2,16 +2,44 @@
 Flavor Extra Specs and Image Properties
 =======================================
 
-TODO: Generic description about Flavor Extra Specs and Image Properties.
+Flavor extra specs and image properties are used to control certain aspects
+or scheduling behavior for a server.
+
+The flavor of a server can be changed during a
+:nova-doc:`resize </user/resize>` operation.
+
+The image of a server can be changed during a
+:nova-doc:`rebuild </contributor/evacuate-vs-rebuild>` operation.
+
+By default, flavor extra specs are controlled by administrators of the cloud.
+If users are authorized to upload their own images to the image service, they
+may be able to specify their own image property requirements.
+
+There are many cases of flavor extra specs and image properties that are for
+the same functionality. In many cases the image property takes precedence over
+the flavor extra spec if both are used in the same server.
 
 Flavor Extra Specs
 ==================
 
-TODO: List the extra specs which we supported at here. The best is the extra
-specs can auto-gen from the nova code.
+Refer to the :nova-doc:`user guide </user/flavors.html#extra-specs>` for a
+list of official extra specs.
+
+While there are standard extra specs, deployments can define their own extra
+specs to be used with host aggregates and custom scheduler filters as
+necessary. See the
+:nova-doc:`reference guide </reference/scheduler-hints-vs-flavor-extra-specs>`
+for more details.
 
 Image Properties
 ================
 
-TODO: List the properties which affect the server creation. The best is the
-properties can auto-gen from the image properties object.
+Refer to the image service documentation for a list of official
+:glance-doc:`image properties </admin/useful-image-properties>` and
+:glance-doc:`metadata definition concepts </user/metadefs-concepts>`.
+
+Unlike flavor extra specs, image properties are standardized in the compute
+service and thus they must be `registered`_ within the compute service before
+they can be used.
+
+.. _registered: https://opendev.org/openstack/nova/src/branch/master/nova/objects/image_meta.py

api-guide/source/general_info.rst

@@ -42,7 +42,7 @@ several key concepts:
 -  **Flavor Extra Specs**
 
    Key and value pairs that can be used to describe the specification of
-   the server which more than just about CPU, disk and RAM. For example,
+   the server which is more than just about CPU, disk and RAM. For example,
    it can be used to indicate that the server created by this flavor has
    PCI devices, etc.
 
@@ -60,7 +60,7 @@ several key concepts:
 -  **Image Properties**
 
    Key and value pairs that can help end users to determine the requirements
-   of the guest os in the image.
+   of the guest operating system in the image.
 
    For more details, please see: :doc:`extra_specs_and_properties`
 

api-guide/source/index.rst

@@ -79,6 +79,7 @@ Contents
     general_info
     server_concepts
     authentication
+    extra_specs_and_properties
     faults
     limits
     links_and_references
@@ -87,8 +88,3 @@ Contents
     request_and_response_formats
     down_cells
     port_with_resource_request
-
-.. toctree::
-    :hidden:
-
-    extra_specs_and_properties