vyos.util: T4773: add camel_to_snake_case conversion

2 files changed, 21 insertions, 0 deletions

diff --git a/python/vyos/util.py b/python/vyos/util.py
index 461df9a6e..e4e2a44ec 100644
--- a/python/vyos/util.py
+++ b/python/vyos/util.py
@@ -1105,3 +1105,10 @@ def sysctl_write(name, value):
         call(f'sysctl -wq {name}={value}')
         return True
     return False
+
+# approach follows a discussion in:
+# https://stackoverflow.com/questions/1175208/elegant-python-function-to-convert-camelcase-to-snake-case
+def camel_to_snake_case(name: str) -> str:
+    pattern = r'\d+|[A-Z]?[a-z]+|\W|[A-Z]{2,}(?=[A-Z][a-z]|\d|\W|$)'
+    words = re.findall(pattern, name)
+    return '_'.join(map(str.lower, words))
diff --git a/src/tests/test_util.py b/src/tests/test_util.py
index 8ac9a500a..d8b2b7940 100644
--- a/src/tests/test_util.py
+++ b/src/tests/test_util.py
@@ -26,3 +26,17 @@ class TestVyOSUtil(TestCase):
 
     def test_sysctl_read(self):
         self.assertEqual(sysctl_read('net.ipv4.conf.lo.forwarding'), '1')
+
+    def test_camel_to_snake_case(self):
+        self.assertEqual(camel_to_snake_case('ConnectionTimeout'),
+                                             'connection_timeout')
+        self.assertEqual(camel_to_snake_case('connectionTimeout'),
+                                             'connection_timeout')
+        self.assertEqual(camel_to_snake_case('TCPConnectionTimeout'),
+                                             'tcp_connection_timeout')
+        self.assertEqual(camel_to_snake_case('TCPPort'),
+                                             'tcp_port')
+        self.assertEqual(camel_to_snake_case('UseHTTPProxy'),
+                                             'use_http_proxy')
+        self.assertEqual(camel_to_snake_case('CustomerID'),
+                                             'customer_id')