From 4a5fa4d64ef3d3cddabbd44ecda546a85abf8981 Mon Sep 17 00:00:00 2001
From: Michael Schmoock <michael@schmoock.net>
Date: Fri, 2 Dec 2022 14:01:12 +0100
Subject: [PATCH] drain: rpcversion check for new format

---
 drain/clnutils.py      | 23 +++++++++++++++++++++++
 drain/drain.py         | 15 +++++----------
 drain/requirements.txt |  1 -
 3 files changed, 28 insertions(+), 11 deletions(-)
 create mode 100644 drain/clnutils.py

diff --git a/drain/clnutils.py b/drain/clnutils.py
new file mode 100644
index 00000000..68161cad
--- /dev/null
+++ b/drain/clnutils.py
@@ -0,0 +1,23 @@
+import re
+
+
+def cln_parse_rpcversion(string):
+    """
+    Parse cln version string to determine RPC version.
+
+    cln switched from 'semver' alike    `major.minor.sub[rcX][-mod]`
+    to ubuntu style with version 22.11  `yy.mm[.patch][-mod]`
+    make sure we can read all of them for (the next 80 years).
+    """
+    rpcversion = string
+    if rpcversion.startswith('v'):  # strip leading 'v'
+        rpcversion = rpcversion[1:]
+    if rpcversion.find('-') != -1:  # strip mods
+        rpcversion = rpcversion[:rpcversion.find('-')]
+    if re.search('.*(rc[\\d]*)$', rpcversion):  # strip release candidates
+        rpcversion = rpcversion[:rpcversion.find('rc')]
+    if rpcversion.count('.') == 1:  # imply patch version 0 if not given
+        rpcversion = rpcversion + '.0'
+
+    # split and convert numeric string parts to actual integers
+    return list(map(int, rpcversion.split('.')))
diff --git a/drain/drain.py b/drain/drain.py
index 1052b704..2f6800ce 100755
--- a/drain/drain.py
+++ b/drain/drain.py
@@ -1,8 +1,8 @@
 #!/usr/bin/env python3
+from clnutils import cln_parse_rpcversion
 from pyln.client import Plugin, Millisatoshi, RpcError
 from utils import get_ours, wait_ours
 import re
-import semver
 import time
 import uuid
 
@@ -23,7 +23,7 @@ HTLC_FEE_PAT = re.compile("^.* HTLC fee: ([0-9]+sat).*$")
 # The route msat helpers are needed because older versions of cln
 # had different msat/msatoshi fields with different types Millisatoshi/int
 def route_set_msat(r, msat):
-    if plugin.rpcversion.major == 0 and plugin.rpcversion.minor < 12:
+    if plugin.rpcversion[0] == 0 and plugin.rpcversion[1] < 12:
         r[plugin.msatfield] = msat.millisatoshis
         r['amount_msat'] = Millisatoshi(msat)
     else:
@@ -488,20 +488,15 @@ def setbalance(plugin, scid: str, percentage: float = 50, chunks: int = 0, retry
 
 @plugin.init()
 def init(options, configuration, plugin):
+    # do all the stuff that needs to be done just once ...
     plugin.getinfo = plugin.rpc.getinfo()
+    plugin.rpcversion = cln_parse_rpcversion(plugin.getinfo.get('version'))
     plugin.configs = plugin.rpc.listconfigs()
     plugin.cltv_final = plugin.configs.get('cltv-final')
 
-    # parse semver string to determine RPC version
-    # strip leading 'v' although semver should ignore it, but it doesn't.
-    rpcversion = plugin.getinfo.get('version')
-    if rpcversion.startswith('v'):
-        rpcversion = rpcversion[1:]
-    plugin.rpcversion = semver.VersionInfo.parse(rpcversion)
-
     # use getroute amount_msat/msatoshi field depending on version
     plugin.msatfield = 'amount_msat'
-    if plugin.rpcversion.major == 0 and plugin.rpcversion.minor < 12:
+    if plugin.rpcversion[0] == 0 and plugin.rpcversion[1] < 12:
         plugin.msatfield = 'msatoshi'
 
     plugin.log("Plugin drain.py initialized")
diff --git a/drain/requirements.txt b/drain/requirements.txt
index 38ec7a50..7ebb30eb 100644
--- a/drain/requirements.txt
+++ b/drain/requirements.txt
@@ -1,2 +1 @@
 pyln-client>=0.12
-semver==2.*