1 files changed, 20 insertions, 0 deletions
diff --git a/python/vyos/template.py b/python/vyos/template.py
index 85e4d12b3..3fbb33acb 100644
--- a/python/vyos/template.py
+++ b/python/vyos/template.py
@@ -207,6 +207,11 @@ def network_from_ipv4(address):
     cidr_prefix = ip_interface(f'{address}/{netmask}').network
     return address_from_cidr(cidr_prefix)
 
+@register_filter('is_interface')
+def is_interface(interface):
+    """ Check if parameter is a valid local interface name """
+    return os.path.exists(f'/sys/class/net/{interface}')
+
 @register_filter('is_ip')
 def is_ip(addr):
     """ Check addr if it is an IPv4 or IPv6 address """
@@ -341,3 +346,18 @@ def get_dhcp_router(interface):
         if 'option routers' in line:
             (_, _, address) = line.split()
             return address.rstrip(';')
+
+@register_filter('natural_sort')
+def natural_sort(iterable):
+    import re
+    from jinja2.runtime import Undefined
+
+    if isinstance(iterable, Undefined) or iterable is None:
+        return list()
+
+    def convert(text):
+        return int(text) if text.isdigit() else text.lower()
+    def alphanum_key(key):
+        return [convert(c) for c in re.split('([0-9]+)', str(key))]
+
+    return sorted(iterable, key=alphanum_key)