feat(test): added graphml2docker helper to create docker compose scen…

…arios with dtn7

tests/docker/README.md

@@ -8,4 +8,7 @@ You can then just use `docker exec` to work from any of the simulated nodes.
 
 Optionally, use tools such as [pumba](https://github.com/alexei-led/pumba) to cause disruptions in the network connections.
 
-An example on how to implement periodically alternating connectivity can be found in the `scenarios/line-3n-loss.sh` script, which should be run after starting the `line-3n.yml` scenario.
+An example on how to implement periodically alternating connectivity can also be found in the `scenarios/line-3n-loss.sh` script, which should be run after starting the `line-3n.yml` scenario.
+
+To build complex network topologies, tools such as [netedit](https://github.com/gh0st42/PONS/tree/master/tools/netedit) can be used to generate a graphml file of the network.
+For convenience, a helper script, `graphml2docker.py` is provided, which automatically creates a docker compose file for the given topology.

tests/docker/graphml2docker.py

@@ -0,0 +1,142 @@
+#!/usr/bin/env python3
+
+import os
+import sys
+import networkx as nx
+
+template_global = """
+version: '3.8'
+name: '{}'
+
+"""
+template_service = """
+  {}:
+    hostname: {}
+    container_name: {}
+    image: {}
+    cap_add:
+      - NET_ADMIN
+    networks: {}
+    environment: {}
+    privileged: true
+    command: -C tcp
+
+"""
+
+template_service_net = """
+      {}:
+        ipv4_address: {}
+"""
+
+template_service_env = """
+      - {}={}"""
+
+template_network = """
+  {}:
+    driver: bridge
+    ipam:
+      config:
+        - subnet: {}
+"""
+
+
+def generate_topology(scenario: str, g: nx.Graph, image="gh0st42/dtn7:bookworm"):
+    g = g.to_undirected()
+    print("Generating topology for scenario %s." % scenario, file=sys.stderr)
+    outfile = template_global.format(scenario)
+
+    services = "services:"
+    networks = "networks:"
+
+    cnt = 1
+    hub_nets = {}
+    net_map = {}
+    for node in g.nodes:
+        node_name = node.lower()
+        if node_name.startswith("net_") or node_name.startswith("subnet_"):
+            subnet = "10.%d.0" % cnt
+            net_name = node_name
+            net_map[net_name] = subnet
+            networks += template_network.format(net_name, "%s.0/24" % subnet)
+            hub_nets[node_name] = 2
+            cnt += 1
+
+    for net in g.edges:
+        net = tuple(sorted(net))
+        if (
+            net[0].lower().startswith("net_")
+            or net[0].lower().startswith("subnet_")
+            or net[1].lower().startswith("net_")
+            or net[1].lower().startswith("subnet_")
+        ):
+            continue
+        net_name = "subnet_%s_%s" % (net[0].lower(), net[1].lower())
+        subnet = "172.33.%d" % cnt
+        networks += template_network.format(net_name, "%s.0/24" % subnet)
+        net_map[net] = subnet
+        cnt += 1
+
+    for node, data in g.nodes(data=True):
+        node_name = node.lower()
+        if node_name.startswith("net_") or node_name.startswith("subnet_"):
+            continue
+        networks_out = ""
+        for e in g.edges(node):
+            if e[0] in hub_nets:
+                node_ip = "%s.%d" % (net_map[e[0]], hub_nets[e[0]])
+                networks_out += template_service_net.format(e[0], node_ip)
+                hub_nets[e[0]] += 1
+            elif e[1] in hub_nets:
+                node_ip = "%s.%d" % (net_map[e[1]], hub_nets[e[1]])
+                networks_out += template_service_net.format(e[1], node_ip)
+                hub_nets[e[1]] += 1
+            else:
+                e = tuple(sorted(e))
+                net_name = "subnet_%s_%s" % (e[0], e[1])
+                if node == e[0]:
+                    node_ip = "%s.%d" % (net_map[e], 2)
+                else:
+                    node_ip = "%s.%d" % (net_map[e], 3)
+                networks_out += template_service_net.format(net_name, node_ip)
+        env = ""
+        for k, v in data.items():
+            if k == "name":
+                continue
+            env += template_service_env.format(str.upper(k), v)
+        # check if node name is a number
+        if node.isdigit():
+            env += template_service_env.format("NODE_ID", node)
+        this_service = template_service.format(
+            node, node.lower(), node.lower(), image, networks_out, env
+        )
+        services += this_service
+    outfile += services
+
+    outfile += networks
+    print(outfile)
+
+
+image = "gh0st42/dtn7:bookworm"
+if len(sys.argv) < 2:
+    print("Usage: %s <graphml_file> [image]" % sys.argv[0])
+    sys.exit(1)
+
+if len(sys.argv) > 2:
+    image = sys.argv[2]
+
+
+g = nx.read_graphml(sys.argv[1])
+
+label_map = {}
+for node, data in g.nodes(data=True):
+    if "name" in data.keys():
+        # print(data["name"])
+        label_map[node] = data["name"]
+        if node.isdigit():
+            data["NODE_ID"] = node
+
+if label_map != {}:
+    nx.relabel_nodes(g, label_map, copy=False)
+
+base_name = os.path.basename(sys.argv[1]).rsplit(".", 1)[0]
+generate_topology(base_name, g, image)