LN: parse source/target channel policies from graphml

Author: pinheadmz

docs/graph.md

@@ -52,9 +52,12 @@ lightning network channel (see [lightning.md](lightning.md)).
   <key id="collect_logs"    attr.name="collect_logs"     attr.type="boolean"  for="node" />
   <key id="build_args"      attr.name="build_args"       attr.type="string"   for="node" />
   <key id="ln"              attr.name="ln"               attr.type="string"   for="node" />
-  <key id="ln-image"        attr.name="ln-image"         attr.type="string"   for="node" />
-  <key id="ln-cb-image"     attr.name="ln-cb-image"      attr.type="string"   for="node" />
-  <key id="channel"         attr.name="channel"          attr.type="number"   for="edge" />
+  <key id="ln_image"        attr.name="ln_image"         attr.type="string"   for="node" />
+  <key id="ln_cb_image"     attr.name="ln_cb_image"      attr.type="string"   for="node" />
+  <key id="ln_config"       attr.name="ln_config"        attr.type="string"   for="node" />
+  <key id="channel_open"    attr.name="channel_open"     attr.type="string"   for="edge" />
+  <key id="source_policy"   attr.name="source_policy"    attr.type="string"   for="edge" />
+  <key id="target_policy"   attr.name="target_policy"    attr.type="string"   for="edge" />
   <graph edgedefault="directed">
     <!-- <nodes> -->
     <!-- <edges> -->
@@ -72,6 +75,9 @@ lightning network channel (see [lightning.md](lightning.md)).
 | collect_logs   | node  | boolean | False     | Whether to collect Bitcoin Core debug logs with Promtail                                                                                                            |
 | build_args     | node  | string  |           | A string of configure options used when building Bitcoin Core from source code, e.g. '--without-gui --disable-tests'                                                |
 | ln             | node  | string  |           | Attach a lightning network node of this implementation (currently only supports 'lnd')                                                                              |
-| ln-image       | node  | string  |           | Specify a lightning network node image from Dockerhub with the format repository/image:tag                                                                          |
-| ln-cb-image    | node  | string  |           | Specify a lnd Circuit Breaker image from Dockerhub with the format repository/image:tag                                                                             |
-| channel        | edge  | number  |           | Indicate that this edge is a lightning channel with this specified capacity                                                                                         |
+| ln_image       | node  | string  |           | Specify a lightning network node image from Dockerhub with the format repository/image:tag                                                                          |
+| ln_cb_image    | node  | string  |           | Specify a lnd Circuit Breaker image from Dockerhub with the format repository/image:tag                                                                             |
+| ln_config      | node  | string  |           | A string of arguments for the lightning network node in command-line format, e.g. '--protocol.wumbo-channels --bitcoin.timelockdelta=80'                            |
+| channel_open   | edge  | string  |           | Indicate that this edge is a lightning channel with these arguments passed to lnd openchannel                                                                       |
+| source_policy  | edge  | string  |           | Update the channel originator policy by passing these arguments passed to lnd updatechanpolicy                                                                      |
+| target_policy  | edge  | string  |           | Update the channel partner policy by passing these arguments passed to lnd updatechanpolicy                                                                         |

docs/lightning.md

@@ -17,18 +17,24 @@ Example:
 
 ## Adding LN channels to graph
 
-LN channels are represented in the graphml file as edges with an extra data element
-with key `"channel"` and a value in satoshis representing channel capacity. Note
-that this data element is the only difference between LN channels and regular bitcoin
-p2p connections. The graph will be considered a `MultiDiGraph` and contain two different
-kinds of edges.
+LN channels are represented in the graphml file as edges with extra data elements
+that correspond to arguments to the lnd `openchannel` and `updatechanpolicy` RPC
+commands. The keys are:
+
+- `"channel_open"` (arguments added to `openchannel`)
+- `"target_policy"` or `"source_policy"` (arguments added to `updatechanpolicy`)
+
+The key `"channel_open"` is required to open a LN channel in warnet, and to
+identify an edge in the graphml file as a LN channel.
 
 Example:
 
 ```
-    <edge id="0" source="0" target="1">
-        <data key="channel">100000</data>
-    </edge>
+<edge id="5" source="0" target="1">
+    <data key="channel_open">--local_amt=100000</data>
+    <data key="source_policy">--base_fee_msat=100  --fee_rate_ppm=5  --time_lock_delta=18</data>
+    <data key="target_policy">--base_fee_msat=2200 --fee_rate_ppm=13 --time_lock_delta=20</data>
+</edge>
 ```
 
 A complete example graph with LN nodes and channels is included in the test

src/schema/graph_schema.json

@@ -30,10 +30,10 @@
       "ln": {
         "type": "string",
         "comment": "Attach a lightning network node of this implementation (currently only supports 'lnd')"},
-      "ln-image": {
+      "ln_image": {
         "type": "string",
         "comment": "Specify a lightning network node image from Dockerhub with the format repository/image:tag"},
-      "ln-cb-image": {
+      "ln_cb_image": {
         "type": "string",
         "comment": "Specify a lnd Circuit Breaker image from Dockerhub with the format repository/image:tag"},
       "ln_config": {
@@ -50,9 +50,15 @@
   "edge": {
     "type": "object",
     "properties": {
-      "channel": {
-        "type": "number",
-        "comment": "Indicate that this edge is a lightning channel with this specified capacity"}
+      "channel_open": {
+        "type": "string",
+        "comment": "Indicate that this edge is a lightning channel with these arguments passed to lnd openchannel"},
+      "source_policy": {
+        "type": "string",
+        "comment": "Update the channel originator policy by passing these arguments passed to lnd updatechanpolicy"},
+      "target_policy": {
+        "type": "string",
+        "comment": "Update the channel partner policy by passing these arguments passed to lnd updatechanpolicy"}
     },
     "additionalProperties": false,
     "required": []

src/warnet/lnnode.py

@@ -68,17 +68,33 @@ def getnewaddress(self):
 
     def getURI(self):
         res = self.lncli("getinfo")
+        if len(res["uris"]) < 1:
+            return None
         return res["uris"][0]
 
     def get_wallet_balance(self):
         res = self.lncli("walletbalance")
         return res
 
-    def open_channel_to_tank(self, index, amt):
+    # returns the channel point in the form txid:output_index
+    def open_channel_to_tank(self, index: int, policy: str) -> str:
         tank = self.warnet.tanks[index]
         [pubkey, host] = tank.lnnode.getURI().split("@")
-        res = self.lncli(f"openchannel --node_key={pubkey} --connect={host} --local_amt={amt}")
-        return res
+        txid = self.lncli(f"openchannel --node_key={pubkey} --connect={host} {policy}")["funding_txid"]
+        # Why doesn't LND return the output index as well?
+        # Do they charge by the RPC call or something?!
+        pending = self.lncli("pendingchannels")
+        for chan in pending["pending_open_channels"]:
+            if txid in chan["channel"]["channel_point"]:
+                return chan["channel"]["channel_point"]
+        raise Exception(f"Opened channel with txid {txid} not found in pending channels")
+
+    def update_channel_policy(self, chan_point: str, policy: str) -> str:
+        ret = self.lncli(f"updatechanpolicy --chan_point={chan_point} {policy}")
+        if len(ret["failed_updates"]) == 0:
+            return ret
+        else:
+            raise Exception(ret)
 
     def connect_to_tank(self, index):
         tank = self.warnet.tanks[index]

src/warnet/warnet.py

@@ -150,7 +150,8 @@ def tanks_from_graph(self):
             # import edges as list of destinations to connect to
             for edge in self.graph.edges(data=True):
                 (src, dst, data) = edge
-                if "channel" in data:
+                # Ignore LN edges for now
+                if "channel_open" in data:
                     continue
                 if src == node_id:
                     tank.init_peers.append(int(dst))

test/data/ln.graphml

@@ -1,35 +1,39 @@
 <?xml version="1.0" encoding="UTF-8"?><graphml xmlns="http://graphml.graphdrawing.org/xmlns">
-  <key attr.name="version"        attr.type="string" for="node" id="version"/>
-  <key attr.name="bitcoin_config" attr.type="string" for="node" id="bitcoin_config"/>
-  <key attr.name="tc_netem"       attr.type="string" for="node" id="tc_netem"/>
-  <key attr.name="ln"             attr.type="string" for="node" id="ln"/>
-  <key attr.name="ln_image"       attr.type="string" for="node" id="ln_image"/>
-  <key attr.name="ln_cb_image"    attr.type="string" for="node" id="ln_cb_image"/>
-  <key attr.name="ln_config"      attr.type="string" for="node" id="ln_config"/>
-  <key attr.name="channel"        attr.type="string" for="edge" id="channel"/>
-  <key attr.name="collect_logs"   attr.type="boolean" for="node" id="collect_logs"/>
-  <key attr.name="image"          attr.type="string" for="node" id="image"/>
+  <key id="version"         attr.name="version"          attr.type="string"   for="node" />
+  <key id="image"           attr.name="image"            attr.type="string"   for="node" />
+  <key id="bitcoin_config"  attr.name="bitcoin_config"   attr.type="string"   for="node" />
+  <key id="tc_netem"        attr.name="tc_netem"         attr.type="string"   for="node" />
+  <key id="exporter"        attr.name="exporter"         attr.type="boolean"  for="node" />
+  <key id="collect_logs"    attr.name="collect_logs"     attr.type="boolean"  for="node" />
+  <key id="build_args"      attr.name="build_args"       attr.type="string"   for="node" />
+  <key id="ln"              attr.name="ln"               attr.type="string"   for="node" />
+  <key id="ln_image"        attr.name="ln_image"         attr.type="string"   for="node" />
+  <key id="ln_cb_image"     attr.name="ln_cb_image"      attr.type="string"   for="node" />
+  <key id="ln_config"       attr.name="ln_config"        attr.type="string"   for="node" />
+  <key id="channel_open"    attr.name="channel_open"     attr.type="string"   for="edge" />
+  <key id="source_policy"   attr.name="source_policy"    attr.type="string"   for="edge" />
+  <key id="target_policy"   attr.name="target_policy"    attr.type="string"   for="edge" />
   <graph edgedefault="directed">
     <node id="0">
         <data key="version">26.0</data>
         <data key="bitcoin_config">-uacomment=w0</data>
         <data key="ln">lnd</data>
+        <data key="ln_image">lightninglabs/lnd:v0.15.5-beta</data>
         <data key="collect_logs">true</data>
     </node>
     <node id="1">
         <data key="version">26.0</data>
         <data key="bitcoin_config">-uacomment=w1</data>
         <data key="ln">lnd</data>
-        <data key="ln_image">lightninglabs/lnd:v0.15.5-beta</data>
         <data key="ln_cb_image">pinheadmz/circuitbreaker:278737d</data>
         <data key="collect_logs">true</data>
-        <data key="ln_config">--bitcoin.timelockdelta=20</data>
     </node>
     <node id="2">
         <data key="version">26.0</data>
         <data key="bitcoin_config">-uacomment=w2</data>
         <data key="ln">lnd</data>
         <data key="ln_cb_image">pinheadmz/circuitbreaker:278737d</data>
+        <data key="ln_config">--bitcoin.timelockdelta=33</data>
     </node>
     <node id="3">
         <data key="version">26.0</data>
@@ -38,13 +42,16 @@
     <edge id="1" source="0" target="1"></edge>
     <edge id="2" source="1" target="2"></edge>
     <edge id="3" source="2" target="3"></edge>
+    <edge id="4" source="2" target="0"></edge>
     <edge id="4" source="3" target="0"></edge>
     <!-- LN channels -->
     <edge id="5" source="0" target="1">
-        <data key="channel">100000</data>
+        <data key="channel_open">--local_amt=100000</data>
+        <data key="target_policy">--base_fee_msat=2200 --fee_rate_ppm=13 --time_lock_delta=20</data>
     </edge>
     <edge id="6" source="1" target="2">
-        <data key="channel">100000</data>
+        <data key="channel_open">--local_amt=100000 --push_amt=50000</data>
+        <data key="source_policy">--base_fee_msat=5500 --fee_rate_ppm=3 --time_lock_delta=40</data>
     </edge>
   </graph>
 </graphml>

test/ln_test.py

@@ -44,18 +44,18 @@ def get_cb_forwards(index):
 base.warcli("scenarios run ln_init")
 base.wait_for_all_scenarios()
 
-print("\nEnsuring channel policy settings")
-chans = json.loads(base.warcli("lncli 1 describegraph"))["edges"]
-for chan in chans:
-    # node_1 or node_2 is tank 1 with its non-default --bitcoin.timelockdelta=20
-    if chan["node1_policy"]["time_lock_delta"] != 20:
-        assert chan["node2_policy"]["time_lock_delta"] == 20
+print("\nEnsuring node-level channel policy settings")
+chan_id = json.loads(base.warcli("lncli 2 listchannels"))["channels"][0]["chan_id"]
+chan = json.loads(base.warcli(f"lncli 2 getchaninfo {chan_id}"))
+# node_1 or node_2 is tank 2 with its non-default --bitcoin.timelockdelta=33
+if chan["node1_policy"]["time_lock_delta"] != 33:
+    assert chan["node2_policy"]["time_lock_delta"] == 33
 
 print("\nEnsuring no circuit breaker forwards yet")
 assert len(get_cb_forwards(1)["forwards"]) == 0
 
 print("\nTest LN payment from 0 -> 2")
-inv = json.loads(base.warcli("lncli 2 addinvoice --amt=1234"))["payment_request"]
+inv = json.loads(base.warcli("lncli 2 addinvoice --amt=2000"))["payment_request"]
 
 print(f"\nGot invoice from node 2: {inv}")
 print("\nPaying invoice from node 0...")
@@ -71,7 +71,32 @@ def check_invoices():
         return False
 base.wait_for_predicate(check_invoices)
 
+print("\nEnsuring channel-level channel policy settings: source")
+payment = json.loads(base.warcli("lncli 0 listpayments"))["payments"][0]
+assert payment["fee_msat"] == "5506"
+
 print("\nEnsuring circuit breaker tracked payment")
 assert len(get_cb_forwards(1)["forwards"]) == 1
 
+print("\nTest LN payment from 2 -> 0")
+inv = json.loads(base.warcli("lncli 0 addinvoice --amt=1000"))["payment_request"]
+
+print(f"\nGot invoice from node 0: {inv}")
+print("\nPaying invoice from node 2...")
+print(base.warcli(f"lncli 2 payinvoice -f {inv}"))
+
+print("Waiting for payment success")
+def check_invoices():
+    invs = json.loads(base.warcli("lncli 0 listinvoices"))["invoices"]
+    if len(invs) > 0 and invs[0]["state"] == "SETTLED":
+        print("\nSettled!")
+        return True
+    else:
+        return False
+base.wait_for_predicate(check_invoices)
+
+print("\nEnsuring channel-level channel policy settings: target")
+payment = json.loads(base.warcli("lncli 2 listpayments"))["payments"][0]
+assert payment["fee_msat"] == "2213"
+
 base.stop_server()