Add support for showing / returing multiple locations (#8)

* Add support for showing / returing multiple locations

* Update readme for multiple locations support

* Adding unit test for multiple backends and showing the multiple locations

* Updating test usecase to run for mitaka version
diff --git a/README.rst b/README.rst
index 0a94ee3..dac4563 100644
--- a/README.rst
+++ b/README.rst
@@ -198,6 +198,26 @@
           allow_credentials: True
           max_age: 86400
 
+Enable Viewing Multiple Locations
+---------------------------------
+If you want to expose all locations available (for example when you have
+multiple backends configured), then you can configure this like so:
+
+.. code-block:: yaml
+
+    glance:
+      server:
+        show_multiple_locations: True
+        location_strategy: store_type
+        store_type_preference: rbd,swift,file
+
+Please note: the show_multiple_locations option is deprecated since Newton and is planned
+             to be handled by policy files _only_ starting with the Pike release.
+
+This feature is convenient in a scenario when you have swift and rbd configured and want to
+benefit from rbd enhancements.
+
+
 Client role
 -----------
 
diff --git a/glance/files/mitaka/glance-api.conf.Debian b/glance/files/mitaka/glance-api.conf.Debian
index b8de9c6..3efb9dc 100644
--- a/glance/files/mitaka/glance-api.conf.Debian
+++ b/glance/files/mitaka/glance-api.conf.Debian
@@ -73,6 +73,7 @@
 # security risk, so use this setting with caution! Setting this to
 # true overrides the show_image_direct_url option. (boolean value)
 #show_multiple_locations = false
+show_multiple_locations = {{ server.get('show_multiple_locations', False) | lower }}
 
 # Maximum size of image a user can upload in bytes. Defaults to
 # 1099511627776 bytes (1 TB).WARNING: this value should only be
@@ -130,6 +131,11 @@
 # 'location_order' and 'store_type'. (string value)
 # Allowed values: location_order, store_type
 #location_strategy = location_order
+{% if server.get('location_strategy', 'location_order') == 'location_order' %}
+location_strategy = location_order
+{% else %}
+location_strategy = store_type
+{% endif %}
 
 # The location of the property protection file.This file contains the
 # rules for property protections and the roles/policies associated
@@ -1855,6 +1861,9 @@
 # option as image location strategy defined by the 'location_strategy'
 # config option. (list value)
 #store_type_preference =
+{% if server.get('location_strategy', 'location_order') == 'store_type' and server.store_type_preference is defined %}
+store_type_preference = {{ server.store_type_preference }}
+{% endif %}
 
 
 [task]
diff --git a/glance/files/newton/glance-api.conf.Debian b/glance/files/newton/glance-api.conf.Debian
index ef3fd74..de83148 100644
--- a/glance/files/newton/glance-api.conf.Debian
+++ b/glance/files/newton/glance-api.conf.Debian
@@ -330,6 +330,7 @@
 # functionality can be achieved with greater granularity by using policies.
 # Please see the Newton release notes for more information.
 #show_multiple_locations = false
+show_multiple_locations = {{ server.get('show_multiple_locations', False) | lower }}
 
 #
 # Maximum size of image a user can upload in bytes.
@@ -602,6 +603,11 @@
 #  (string value)
 # Allowed values: location_order, store_type
 #location_strategy = location_order
+{% if server.get('location_strategy', 'location_order') == 'location_order' %}
+location_strategy = location_order
+{% else %}
+location_strategy = store_type
+{% endif %}
 
 #
 # The location of the property protection file.
@@ -4278,6 +4284,9 @@
 #
 #  (list value)
 #store_type_preference =
+{% if server.get('location_strategy', 'location_order') == 'store_type' and server.store_type_preference is defined %}
+store_type_preference = {{ server.store_type_preference }}
+{% endif %}
 
 
 [task]
diff --git a/glance/files/ocata/glance-api.conf.Debian b/glance/files/ocata/glance-api.conf.Debian
index 8c5b479..8b3f40d 100644
--- a/glance/files/ocata/glance-api.conf.Debian
+++ b/glance/files/ocata/glance-api.conf.Debian
@@ -330,6 +330,7 @@
 # functionality can be achieved with greater granularity by using policies.
 # Please see the Newton release notes for more information.
 #show_multiple_locations = false
+show_multiple_locations = {{ server.get('show_multiple_locations', False) | lower }}
 
 #
 # Maximum size of image a user can upload in bytes.
@@ -602,6 +603,11 @@
 #  (string value)
 # Allowed values: location_order, store_type
 #location_strategy = location_order
+{% if server.get('location_strategy', 'location_order') == 'location_order' %}
+location_strategy = location_order
+{% else %}
+location_strategy = store_type
+{% endif %}
 
 #
 # The location of the property protection file.
@@ -4344,6 +4350,9 @@
 #
 #  (list value)
 #store_type_preference =
+{% if server.get('location_strategy', 'location_order') == 'store_type' and server.store_type_preference is defined %}
+store_type_preference = {{ server.store_type_preference }}
+{% endif %}
 
 
 [task]
diff --git a/tests/pillar/single_multiple_backends.sls b/tests/pillar/single_multiple_backends.sls
new file mode 100644
index 0000000..4a9d6a2
--- /dev/null
+++ b/tests/pillar/single_multiple_backends.sls
@@ -0,0 +1,70 @@
+glance:
+  server:
+    enabled: true
+    version: mitaka
+    workers: 1
+    show_multiple_locations: True
+    location_strategy: store_type
+    store_type_preference: rbd,swift
+    database:
+      engine: mysql
+      host: localhost
+      port: 3306
+      name: glance
+      user: glance
+      password: password
+    registry:
+      host: 127.0.0.1
+      port: 9191
+    bind:
+      address: 127.0.0.1
+      port: 9292
+    identity:
+      engine: keystone
+      host: 127.0.0.1
+      port: 35357
+      user: glance
+      password: password
+      region: RegionOne
+      tenant: service
+      endpoint_type: internalURL
+    message_queue:
+      engine: rabbitmq
+      host: 127.0.0.1
+      port: 5672
+      user: openstack
+      password: password
+      virtual_host: '/openstack'
+    storage:
+      engine: swift,rbd,http
+      # Rbd configuration
+      user: glance
+      pool: glance-images
+      chunk_size: 8
+      client_glance_key: AQAqcXhWk+3UARAAGmV4USB6I7wLJ/W+dVbUWw==
+      # Swift configuration
+      swift:
+        store:
+          # admin_tenants:
+          auth:
+            address: http://127.0.0.1:5000/v2.0
+            insecure: false
+            version: 2
+          cacert: /etc/ssl/certs/ca-certificates.crt
+          # config_file:
+          container: glance
+          create_container_on_put: true
+          endpoint: swift
+          endpoint_type: internalURL
+          expire_soon_interval: 60
+          key: someRandomPassword
+          large_object_size: 5120
+          large_object_chunk_size: 200
+          multi_tenant: false
+          multiple_containers_seed: 0
+          retry_get_count: 5
+          region: RegionOne
+          service_type: object-store
+          ssl_compression: false
+          use_trusts: false
+          user: 2ec7966596504f59acc3a76b3b9d9291:glance-project