Add support for Host header in REST queries

Can use host request headers if enable_host_header is set to true
in config file. If host header is not specified or host header is
turned off, it will use the default api_base_uri.

Also added unit tests.

Change-Id: Ia353c116485f3e7112bcfde11457cdf7fe006422
Closes-bug: 1446387

designate/api/__init__.py

@@ -25,6 +25,8 @@ cfg.CONF.register_opts([
                help='Number of api worker processes to spawn'),
     cfg.IntOpt('threads', default=1000,
                help='Number of api greenthreads to spawn'),
+    cfg.BoolOpt('enable-host-header', default=False,
+               help='Enable host request headers'),
     cfg.StrOpt('api-base-uri', default='http://127.0.0.1:9001/'),
     cfg.StrOpt('api_host', default='0.0.0.0',
                help='API Host'),

designate/api/versions.py

@@ -16,6 +16,8 @@
 import flask
 from oslo_config import cfg
 
+cfg.CONF.import_opt('enable_host_header', 'designate.api', group='service:api')
+
 
 def factory(global_config, **local_conf):
     app = flask.Flask('designate.api.versions')
@@ -24,24 +26,32 @@ def factory(global_config, **local_conf):
 
     base = cfg.CONF['service:api'].api_base_uri.rstrip('/')
 
-    def _version(version, status):
+    def _host_header_links():
+        del versions[:]
+        host_url = flask.request.host_url
+        _version('v1', 'DEPRECATED', host_url)
+        _version('v2', 'CURRENT', host_url)
+
+    def _version(version, status, base_uri):
         versions.append({
             'id': '%s' % version,
             'status': status,
             'links': [{
-                'href': base + '/' + version,
+                'href': base_uri + '/' + version,
                 'rel': 'self'
             }]
         })
 
     if cfg.CONF['service:api'].enable_api_v1:
-        _version('v1', 'DEPRECATED')
+        _version('v1', 'DEPRECATED', base)
 
     if cfg.CONF['service:api'].enable_api_v2:
-        _version('v2', 'CURRENT')
+        _version('v2', 'CURRENT', base)
 
     @app.route('/', methods=['GET'])
     def version_list():
+        if cfg.CONF['service:api'].enable_host_header:
+            _host_header_links()
 
         return flask.jsonify({
             "versions": {

designate/objects/adapters/api_v2/base.py

@@ -21,6 +21,7 @@ from designate.objects import base as obj_base
 LOG = logging.getLogger(__name__)
 
 cfg.CONF.import_opt('api_base_uri', 'designate.api', group='service:api')
+cfg.CONF.import_opt('enable_host_header', 'designate.api', group='service:api')
 
 
 class APIv2Adapter(base.DesignateAdapter):
@@ -77,8 +78,16 @@ class APIv2Adapter(base.DesignateAdapter):
 
     @classmethod
     def _get_resource_links(cls, object, request):
+        if cfg.CONF['service:api'].enable_host_header:
+            try:
+                base_uri = request.host_url
+            except Exception:
+                base_uri = cls.BASE_URI
+        else:
+            base_uri = cls.BASE_URI
+
         return {'self': '%s%s/%s' %
-                (cls.BASE_URI, cls._get_path(request), object.id)}
+                (base_uri, cls._get_path(request), object.id)}
 
     @classmethod
     def _get_path(cls, request):
@@ -119,8 +128,16 @@ class APIv2Adapter(base.DesignateAdapter):
         if extra_params is not None:
             params.update(extra_params)
 
+        if cfg.CONF['service:api'].enable_host_header:
+            try:
+                base_uri = request.host_url
+            except Exception:
+                base_uri = cls.BASE_URI
+        else:
+            base_uri = cls.BASE_URI
+
         href = "%s%s?%s" % (
-            cls.BASE_URI,
+            base_uri,
             cls._get_path(request),
             parse.urlencode(params))
 

designate/tests/test_api/test_v2/test_hostheaders.py

@@ -0,0 +1,52 @@
+# Copyright (c) 2015 Rackspace Hosting
+#
+# Author: Mimi Lee <mimi.lee@rackspace.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from designate.tests.test_api.test_v2 import ApiV2TestCase
+
+
+class ApiV2HostHeadersTest(ApiV2TestCase):
+    def setUp(self):
+        super(ApiV2HostHeadersTest, self).setUp()
+
+        # Ensure v2 API and host headers are enabled
+        self.config(enable_api_v2=True, group='service:api')
+        self.config(enable_host_header=True, group='service:api')
+
+    def test_host_header(self):
+        # Create a zone with host header
+        fixture = self.get_domain_fixture(fixture=0)
+        response = self.client.post_json('/zones/',
+                                         fixture,
+                                         headers={'Host': 'testhost.com'})
+        # Check the headers are what we expect
+        self.assertEqual(202, response.status_int)
+        self.assertEqual('application/json', response.content_type)
+
+        # Check the host request header url
+        self.assertTrue('http://testhost.com/zones/' in
+                response.json_body['links']['self'])
+
+        # Get zone with host header
+        response = self.client.get('/zones/',
+                                   headers={'Host': 'testhost.com'})
+
+        # Check the headers are what we expect
+        self.assertEqual(200, response.status_int)
+        self.assertEqual('application/json', response.content_type)
+
+        # Check the host request header url
+        self.assertTrue('http://testhost.com/zones' in
+                response.json_body['links']['self'])

etc/designate/designate.conf.sample

@@ -84,6 +84,9 @@ debug = False
 # Number of api greenthreads to spawn
 #threads = 1000
 
+# Enable host request headers
+#enable_host_header = False
+
 # The base uri used in responses
 #api_base_uri = 'http://127.0.0.1:9001/'