FIX: ovs-ofctl missing flow table issue

source/topology_plan.py

@@ -43,10 +43,13 @@ class PlannedNode:
     Args:
         name: Logical node name used by Mininet.
         type: Concrete semantic node type to create.
+        switch_fail_mode: Optional Open vSwitch fail mode selected by the
+            planner for switch nodes.  Non-switch nodes leave this unset.
     """
 
     name: str
     type: NodeType
+    switch_fail_mode: Optional[str] = None
 
 
 @dataclass(frozen=True)
@@ -275,7 +278,13 @@ def _plan_nodes(topology: Topology) -> Tuple[PlannedNode, ...]:
     """
 
     return tuple(
-        PlannedNode(name=node.name, type=node.type)
+        PlannedNode(
+            name=node.name,
+            type=node.type,
+            switch_fail_mode=(
+                "standalone" if node.type is NodeType.SWITCH else None
+            ),
+        )
         for node in topology.nodes
     )
 
@@ -797,6 +806,9 @@ def _self_test() -> None:
 
     assert len(execution_plan.nodes) == 3
     assert len(execution_plan.links) == 2
+    assert next(
+        node for node in execution_plan.nodes if node.name == "s1"
+    ).switch_fail_mode == "standalone"
     assert execution_plan.links[0].endpoints[1].logical_interface == "client"
     assert execution_plan.links[0].endpoints[0].interface_name == "h1-eth0"
     assert execution_plan.links[1].endpoints[0].interface_name == "r0-eth0"

source/topology_renderer.py

@@ -322,10 +322,11 @@ def render_python(plan: ExecutionPlan) -> str:
             )
         elif node.type is NodeType.SWITCH:
             lines.append(
-                "        nodes[%s] = net.addSwitch(%s)"
+                "        nodes[%s] = net.addSwitch(%s, failMode=%r)"
                 % (
                     _python_string(node.name),
                     _python_string(node.name),
+                    node.switch_fail_mode,
                 )
             )
         else:
@@ -469,7 +470,7 @@ def _self_test() -> None:
     ast.parse(source)
 
     assert "net.addHost('h1', ip=None)" in source
-    assert "net.addSwitch('s1')" in source
+    assert "net.addSwitch('s1', failMode='standalone')" in source
     assert "net.addLink(" in source
     assert "cls=TCLink" in source
     assert "dnsmasq" in source