Fix Error while creating link: Port 0 is not allocated. when you have an invalid interface

Fix #744

gns3server/controller/udp_link.py

@@ -69,7 +69,12 @@ class UDPLink(Link):
             "rport": self._node1_port,
             "type": "nio_udp"
         }
+        try:
             yield from node2.post("/adapters/{adapter_number}/ports/{port_number}/nio".format(adapter_number=adapter_number2, port_number=port_number2), data=data)
+        except Exception as e:
+            # We clean the first NIO
+            yield from node1.delete("/adapters/{adapter_number}/ports/{port_number}/nio".format(adapter_number=adapter_number1, port_number=port_number1))
+            raise e
         self._created = True
 
     @asyncio.coroutine
@@ -77,6 +82,8 @@ class UDPLink(Link):
         """
         Delete the link and free the resources
         """
+        if not self._created:
+            return
         try:
             node1 = self._nodes[0]["node"]
             adapter_number1 = self._nodes[0]["adapter_number"]

tests/controller/test_udp_link.py

@@ -93,6 +93,72 @@ def test_create(async_run, project):
     })
 
 
+def test_create_one_side_failure(async_run, project):
+    compute1 = MagicMock()
+    compute2 = MagicMock()
+
+    node1 = Node(project, compute1, "node1", node_type="vpcs")
+    node1._ports = [EthernetPort("E0", 0, 0, 4)]
+    node2 = Node(project, compute2, "node2", node_type="vpcs")
+    node2._ports = [EthernetPort("E0", 0, 3, 1)]
+
+    @asyncio.coroutine
+    def subnet_callback(compute2):
+        """
+        Fake subnet callback
+        """
+        return ("192.168.1.1", "192.168.1.2")
+
+    compute1.get_ip_on_same_subnet.side_effect = subnet_callback
+
+    link = UDPLink(project)
+    async_run(link.add_node(node1, 0, 4))
+
+    @asyncio.coroutine
+    def compute1_callback(path, data={}):
+        """
+        Fake server
+        """
+        if "/ports/udp" in path:
+            response = MagicMock()
+            response.json = {"udp_port": 1024}
+            return response
+
+    @asyncio.coroutine
+    def compute2_callback(path, data={}):
+        """
+        Fake server
+        """
+        if "/ports/udp" in path:
+            response = MagicMock()
+            response.json = {"udp_port": 2048}
+            return response
+        elif "/adapters" in path:
+            raise aiohttp.web.HTTPConflict(text="Error when creating the NIO")
+
+    compute1.post.side_effect = compute1_callback
+    compute1.host = "example.com"
+    compute2.post.side_effect = compute2_callback
+    compute2.host = "example.org"
+    with pytest.raises(aiohttp.web.HTTPConflict):
+        async_run(link.add_node(node2, 3, 1))
+
+    compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
+        "lport": 1024,
+        "rhost": "192.168.1.2",
+        "rport": 2048,
+        "type": "nio_udp"
+    })
+    compute2.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/3/ports/1/nio".format(project.id, node2.id), data={
+        "lport": 2048,
+        "rhost": "192.168.1.1",
+        "rport": 1024,
+        "type": "nio_udp"
+    })
+    # The link creation has failed we rollback the nio
+    compute1.delete.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id))
+
+
 def test_delete(async_run, project):
     compute1 = MagicMock()
     compute2 = MagicMock()