Make it possible to get the request_id from python clients

This is so callers can extract the request_id for tracing
and associating with events (this is especially useful in Heat
where there are a lot of client calls and one needs to map
a Heat action to the underlying service requests).

Partial-bug: #1342922
Change-Id: I6c60946c8fcdb44f1b18733296982bf0d32334dc

openstack/common/apiclient/base.py

@@ -488,6 +488,8 @@ def get(self):
         new = self.manager.get(self.id)
         if new:
             self._add_details(new._info)
+            self._add_details(
+                {'x_request_id': self.manager.client.last_request_id})
 
     def __eq__(self, other):
         if not isinstance(other, Resource):

openstack/common/apiclient/client.py

@@ -98,6 +98,7 @@ def __init__(self,
         self.http = http or requests.Session()
 
         self.cached_token = None
+        self.last_request_id = None
 
     def _http_log_req(self, method, url, kwargs):
         if not self.debug:
@@ -177,6 +178,8 @@ def request(self, method, url, **kwargs):
                                start_time, time.time()))
         self._http_log_resp(resp)
 
+        self.last_request_id = resp.headers.get('x-openstack-request-id')
+
         if resp.status_code >= 400:
             _logger.debug(
                 "Request returned failure status: %s",
@@ -323,6 +326,10 @@ def client_request(self, method, url, **kwargs):
         return self.http_client.client_request(
             self, method, url, **kwargs)
 
+    @property
+    def last_request_id(self):
+        return self.http_client.last_request_id
+
     def head(self, url, **kwargs):
         return self.client_request("HEAD", url, **kwargs)
 

openstack/common/apiclient/fake_client.py

@@ -168,6 +168,8 @@ def client_request(self, client, method, url, **kwargs):
         else:
             status, body = resp
             headers = {}
+        self.last_request_id = headers.get('x-openstack-request-id',
+                                           'req-test')
         return TestResponse({
             "status_code": status,
             "text": body,

tests/unit/apiclient/test_base.py

@@ -66,16 +66,23 @@ class FakeHTTPClient(fake_client.FakeHTTPClient):
     crud_resource_json = {"id": "1", "domain_id": "my-domain"}
 
     def get_human_resources(self, **kw):
-        return (200, {}, {'human_resources': [
-            {'id': 1, 'name': '256 MB Server'},
-            {'id': 2, 'name': '512 MB Server'},
-            {'id': 'aa1', 'name': '128 MB Server'}
-        ]})
+        return (200, {},
+                {'human_resources': [
+                    {'id': 1, 'name': '256 MB Server'},
+                    {'id': 2, 'name': '512 MB Server'},
+                    {'id': 'aa1', 'name': '128 MB Server'},
+                    {'id': 3, 'name': '4 MB Server'},
+                ]})
 
     def get_human_resources_1(self, **kw):
         res = self.get_human_resources()[2]['human_resources'][0]
         return (200, {}, {'human_resource': res})
 
+    def get_human_resources_3(self, **kw):
+        res = self.get_human_resources()[2]['human_resources'][3]
+        return (200, {'x-openstack-request-id': 'req-flappy'},
+                {'human_resource': res})
+
     def put_human_resources_1(self, **kw):
         kw = kw["json"]["human_resource"].copy()
         kw["id"] = "1"
@@ -152,6 +159,18 @@ def test_resource_lazy_getattr(self):
         # Missing stuff still fails after a second get
         self.assertRaises(AttributeError, getattr, f, 'blahblah')
 
+    def test_resource_req_id(self):
+        f = HumanResource(self.tc.human_resources, {'id': 1})
+        self.assertEqual(f.name, '256 MB Server')
+        self.assertEqual(f.x_request_id, 'req-test')
+        self.http_client.assert_called('GET', '/human_resources/1')
+
+    def test_resource_req_id_header(self):
+        f = HumanResource(self.tc.human_resources, {'id': 3})
+        self.assertEqual(f.name, '4 MB Server')
+        self.assertEqual(f.x_request_id, 'req-flappy')
+        self.http_client.assert_called('GET', '/human_resources/3')
+
     def test_eq(self):
         # Two resources of the same type with the same id: equal
         r1 = base.Resource(None, {'id': 1, 'name': 'hi'})