[openstack|storage] Added storage example to set the account quota

See also #1632

lib/fog/openstack/examples/storage/set-account-quota.rb

@@ -0,0 +1,66 @@
+require 'fog'
+require 'pp'
+
+#
+# This example sets the account quota (in bytes) for the tenant demo@test.lan
+# using an admin account (admin has the reseller user role).
+#
+# Uses the account impersonation feature recently added to the
+# OpenStack Storage service in Fog (See https://github.com/fog/fog/pull/1632).
+# 
+# Should be available in Fog 1.10.0+1.
+#
+# Setting account quotas is only supported in Swift 1.8.0+ 
+# using the brand new account_quota middleware introduced in 
+# OpenStack Grizzly (currently unreleased as of 2013/04/03).
+#
+# https://github.com/openstack/swift/blob/master/swift/common/middleware/account_quotas.py
+#
+
+auth_url = 'https://identity.test.lan/v2.0/tokens'
+user = 'admin@test.lan'
+password = 'secret'
+
+Excon.defaults[:ssl_verify_peer] = false
+
+# 
+# We are going to use the Identity (Keystone) service
+# to retrieve the list of tenants available and find
+# the tenant we want to set the quotas for.
+#
+id = Fog::Identity.new :provider => 'OpenStack',
+                       :openstack_auth_url => auth_url,
+                       :openstack_username => user,
+                       :openstack_api_key  => password
+
+#
+# Storage service (Swift)
+#
+st = Fog::Storage.new :provider => 'OpenStack',
+                      :openstack_auth_url => auth_url,
+                      :openstack_username => user,
+                      :openstack_api_key  => password
+
+id.tenants.each do |t|
+  # We want to set the account quota for tenant demo@test.lan
+  next unless t.name == 'demo@test.lan'
+
+  # We've found the tenant, impersonate the account
+  # (the account prefix AUTH_ may be different for you, double check it).
+  puts "Changing account to #{t.name}"
+  st.change_account "AUTH_#{t.id}"
+
+  # Now we're adding the required header to the demo@test.lan 
+  # tenant account, limiting the account bytes to 1048576 (1MB)
+  #
+  # Uploading more than 1MB will return 413: Request Entity Too Large
+  st.request :method => 'POST',
+             :headers => { 'X-Account-Meta-Quota-Bytes' => '1048576' }
+
+  # We can list the account details to verify the new 
+  # header has been added
+  pp st.request :method => 'HEAD'
+end
+
+# Restore the account we were using initially (admin@test.lan)
+st.reset_account_name