Add a new method get_router_info to L3 agent extension API

This can be useful for VPNaaS agent extension. [1]

[1] I0b86c432e4b2210e5f2a73a7e3ba16d10467f0f2

Related-Bug: #1692128
Change-Id: I5cfeb8db501b0cdba95c003ec6281c6a55a73b49

doc/source/contributor/internals/l3_agent_extensions.rst

@@ -36,3 +36,4 @@ router information to L3 agent extensions::
 #. get_routers_in_project
 #. get_router_hosting_port
 #. is_router_in_namespace
+#. get_router_info

neutron/agent/l3/l3_agent_extension_api.py

@@ -65,3 +65,7 @@ class L3AgentExtensionAPI(object):
         local_namespaces = self._local_namespaces()
         ri = self._router_info.get(router_id)
         return ri and ri.ns_name in local_namespaces
+
+    def get_router_info(self, router_id):
+        """Return RouterInfo for the given router id."""
+        return self._router_info.get(router_id)

neutron/tests/unit/agent/l3/test_l3_agent_extension_api.py

@@ -94,3 +94,14 @@ class TestL3AgentExtensionApi(base.BaseTestCase):
             api_object = l3_agent_api.L3AgentExtensionAPI(router_info)
             router_in_ns = api_object.is_router_in_namespace(ri.router_id)
             self.assertFalse(router_in_ns)
+
+    def test_get_router_info(self):
+        router_info, ri = self._prepare_router_data()
+        api_object = l3_agent_api.L3AgentExtensionAPI(router_info)
+        self.assertEqual(ri, api_object.get_router_info(self.router_id))
+
+    def test_get_router_info_nonexistent(self):
+        router_info, ri = self._prepare_router_data()
+        api_object = l3_agent_api.L3AgentExtensionAPI(router_info)
+        self.assertIsNone(
+            api_object.get_router_info(uuidutils.generate_uuid()))

releasenotes/notes/l3-agent-api-get-router-info-93c316a792a9d87f.yaml

@@ -0,0 +1,4 @@
+---
+features:
+  - A new method ``get_router_info`` has been added to
+    ``L3AgentExtensionAPI``.