utils/generate_config.py: Add ipaddr_index filter

v5 -> v6:
- IP address can be IPv4 or IPv6;
- add fallback to 'str' type for py3-incompatible 'unicode';
- fix pylint complaints (silence unnecessary ones);

Change-Id: Iea1049a7f5379e9bcb4b785fdd810b67f51c94ab
Signed-off-by: Guillermo Herrero <guillermo.herrero@enea.com>
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/utils/generate_config.py b/utils/generate_config.py
index b65bf7f..353cd47 100755 (executable)
--- a/utils/generate_config.py
+++ b/utils/generate_config.py
@@ -1,6 +1,7 @@
 #!/usr/bin/python
 """This module does blah blah."""
 import argparse
+import ipaddress
 import yaml
 from jinja2 import Environment, FileSystemLoader
 
@@ -9,8 +10,19 @@ PARSER.add_argument("--yaml", "-y", type=str, required=True)
 PARSER.add_argument("--jinja2", "-j", type=str, required=True)
 ARGS = PARSER.parse_args()
 
+# Custom filter to allow simple IP address operations returning
+# a new address from an upper or lower (negative) index
+def ipaddr_index(base_address, index):
+    """Return IP address in given network at given index"""
+    try:
+        base_address_str = unicode(base_address)
+    #pylint: disable=unused-variable
+    except NameError as ex:
+        base_address_str = str(base_address)
+    return ipaddress.ip_address(base_address_str) + int(index)
 
 ENV = Environment(loader=FileSystemLoader('./'))
+ENV.filters['ipaddr_index'] = ipaddr_index
 
 with open(ARGS.yaml) as _:
     DICT = yaml.safe_load(_)
@@ -20,4 +32,5 @@ with open(ARGS.yaml) as _:
 
 # Render template and print generated conf to console
 TEMPLATE = ENV.get_template(ARGS.jinja2)
+#pylint: disable=superfluous-parens
 print(TEMPLATE.render(conf=DICT))