Add flexible destination format string to ec2.py

This allows us to construct hostnames from a format string
plus ec2 tag values.

1 files changed, 5 insertions, 1 deletions

diff --git a/inventory/aws/ec2.py b/inventory/aws/ec2.py
index 0f7c19857..f4e029553 100644
--- a/inventory/aws/ec2.py
+++ b/inventory/aws/ec2.py
@@ -215,6 +215,8 @@ class Ec2Inventory(object):
         # Destination addresses
         self.destination_variable = config.get('ec2', 'destination_variable')
         self.vpc_destination_variable = config.get('ec2', 'vpc_destination_variable')
+        self.destination_format = config.get('ec2', 'destination_format')
+        self.destination_format_tags = config.get('ec2', 'destination_format_tags', '').split(',')
 
         # Route53
         self.route53_enabled = config.getboolean('ec2', 'route53')
@@ -411,7 +413,9 @@ class Ec2Inventory(object):
             return
 
         # Select the best destination address
-        if instance.subnet_id:
+        if self.destination_format and self.destination_format_tags:
+            dest = self.destination_format.format(*[ getattr(instance, 'tags').get(tag, 'nil') for tag in self.destination_format_tags ])
+        elif instance.subnet_id:
             dest = getattr(instance, self.vpc_destination_variable, None)
             if dest is None:
                 dest = getattr(instance, 'tags').get(self.vpc_destination_variable, None)