From 8c5cc44946229479135ef24194e970eb504083f5 Mon Sep 17 00:00:00 2001
From: LeoVerto <LeoVerto@users.noreply.github.com>
Date: Wed, 1 Jul 2020 15:46:24 +0200
Subject: [PATCH] Fix KeyError when networks with no gateway exist

---
 docker-net-graph.py     | 2 +-
 test/docker-compose.yml | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/docker-net-graph.py b/docker-net-graph.py
index 44cabc9..bd00804 100755
--- a/docker-net-graph.py
+++ b/docker-net-graph.py
@@ -63,7 +63,7 @@ def get_networks(client: docker.DockerClient, verbose: bool) -> typing.Dict[str,
 
     for net in sorted(client.networks.list(), key=lambda k: k.name):
         try:
-            gateway = net.attrs["IPAM"]["Config"][0]["Gateway"]
+            gateway = net.attrs["IPAM"]["Config"][0]["Subnet"]
         except (KeyError, IndexError):
             # This network doesn't seem to be used, skip it
             continue
diff --git a/test/docker-compose.yml b/test/docker-compose.yml
index b555eba..e149f32 100644
--- a/test/docker-compose.yml
+++ b/test/docker-compose.yml
@@ -22,6 +22,7 @@ services:
         - network_a
         - network_b
         - network_c
+        - no_gateway
     host_service:
       container_name: host_service
       image: leoverto/dummy-image
@@ -36,3 +37,11 @@ networks:
   network_b:
   network_c:
   empty_network:
+  no_gateway:
+    driver: bridge
+    driver_opts:
+      com.docker.network.bridge.name: br-no-gateway
+    ipam:
+      driver: default
+      config:
+        - subnet: 172.22.1.0/24