doc container quotas

Grizzly introduced the container quota feature in object storage

fixes bug 1090653

Change-Id: I2779633ba63b8aafc9c00861a952c122ca2e9ce8

doc/src/docbkx/openstack-object-storage-admin/objectstorageadmin.xml

@@ -1571,6 +1571,31 @@ metadata which can be used for stats purposes.
 </section>
     </section>
 
+
+<section xml:id="object-storage-container-quotas">
+ <title>Container Quotas</title>
+    <para>The container_quotas middleware implements simple quotas that can be
+    imposed on swift containers by a user with the ability to set container
+    metadata, most likely the account administrator. This can be useful for
+    limiting the scope of containers that are delegated to non-admin users, exposed
+    to formpost uploads, or just as a self-imposed sanity check.</para>
+
+    <para>Any object PUT operations that exceed these quotas return a 413 response
+    (request entity too large) with a descriptive body.</para>
+
+    <para>Quotas are subject to several limitations: eventual consistency, the timeliness
+    of the cached container_info (60 second ttl by default), and it's unable to
+    reject chunked transfer uploads that exceed the quota (though once the quota
+    is exceeded, new chunked transfers will be refused).</para>
+
+    <para>Quotas are set by adding meta values to the container, and are validated when
+    set:
+    <itemizedlist>
+    <listitem><para>X-Container-Meta-Quota-Bytes: Maximum size of the container, in bytes.</para></listitem>
+    <listitem><para>X-Container-Meta-Quota-Count: Maximum object count of the container.</para></listitem>
+    </itemizedlist>
+    </para>
+</section>
     </section>
 
     <section xml:id="configuring-openstack-object-storage-with-s3_api">