Add S3 SigV4 location support

Change-Id: I2ee8cb968ae2cf34558546b1be6be5273c2f52d3
Closes-Bug: #1822322

lib/swift_context.py

@@ -10,6 +10,7 @@ from charmhelpers.core.hookenv import (
     unit_get,
     service_name,
     leader_get,
+    DEBUG,
 )
 from charmhelpers.contrib.openstack.context import (
     OSContextGenerator,
@@ -24,7 +25,11 @@ from charmhelpers.contrib.network.ip import (
     format_ipv6_addr,
     get_ipv6_addr,
 )
-from charmhelpers.contrib.openstack.utils import get_host_ip
+from charmhelpers.contrib.openstack.utils import (
+    os_release,
+    CompareOpenStackReleases,
+    get_host_ip,
+)
 
 
 SWIFT_HASH_FILE = '/var/lib/juju/swift-hash-path.conf'
@@ -82,6 +87,20 @@ class SwiftRingContext(OSContextGenerator):
         return ctxt
 
 
+class SwiftS3Context(OSContextGenerator):
+
+    def __call__(self):
+        ctxt = {}
+        if CompareOpenStackReleases(os_release('swift-common')) >= 'queens':
+            if config('region'):
+                ctxt['location'] = config('region')
+            else:
+                log("Region config not provided so location cannot be set - "
+                    "required from S3 Sig V4 support to work correctly", DEBUG)
+
+        return ctxt
+
+
 class SwiftIdentityContext(OSContextGenerator):
     interfaces = ['identity-service']
 

lib/swift_utils.py

@@ -22,6 +22,7 @@ from lib.swift_context import (
     SwiftRingContext,
     ApacheSSLContext,
     MemcachedContext,
+    SwiftS3Context,
 )
 
 import charmhelpers.contrib.openstack.context as context
@@ -144,6 +145,7 @@ CONFIG_FILES = OrderedDict([
     }),
     (SWIFT_PROXY_CONF, {
         'hook_contexts': [SwiftIdentityContext(),
+                          SwiftS3Context(),
                           context.BindHostContext(),
                           context.AMQPContext(ssl_dir=SWIFT_CONF_DIR)],
         'services': ['swift-proxy'],

templates/queens/proxy-server.conf

@@ -131,6 +131,9 @@ auth_version = 3
 
 [filter:swift3]
 use = egg:swift3#swift3
+{% if location -%}
+location = {{ location }}
+{% endif -%}
 {% endif %}
 
 {% if auth_type == 'swauth' %}

templates/rocky/proxy-server.conf

@@ -131,6 +131,9 @@ auth_version = 3
 
 [filter:s3api]
 use = egg:swift#s3api
+{% if location -%}
+location = {{ location }}
+{% endif -%}
 {% endif %}
 
 {% if auth_type == 'swauth' %}

unit_tests/test_swift_context.py

@@ -151,3 +151,24 @@ class SwiftContextTestCase(unittest.TestCase):
             self.assertEqual(hash_, fd.read())
 
         self.assertTrue(mock_config.called)
+
+
+class SwiftS3ContextTestCase(unittest.TestCase):
+
+    @mock.patch('lib.swift_context.os_release')
+    @mock.patch('lib.swift_context.config')
+    def test_location(self, mock_config, mock_os_release):
+        cfg = {'region': 'London'}
+
+        def fake_config(key):
+            return cfg.get(key)
+
+        mock_config.side_effect = fake_config
+
+        mock_os_release.return_value = 'queens'
+        ctxt = swift_context.SwiftS3Context()
+        self.assertEqual({'location': 'London'}, ctxt())
+
+        mock_os_release.return_value = 'pike'
+        ctxt = swift_context.SwiftS3Context()
+        self.assertEqual({}, ctxt())