Trouble selecting particular entry in list - ansible

Question

I am having a devil of a time sorting this out so any help is appreciated. I know I need to use selectattr but cannot figure out how exactly.
Using ansible I need to find the address associated with the neighbor that has a route map named BGP_TO_EC applied. I know selectattr will be involved but cannot figure out how exactly.
TIA
Parsed config:
address_family:
- afi: ipv4
neighbor:
- activate: true
address: 10.1.1.1
nexthop_self:
set: true
route_maps:
- name: BGP_TO_EC
out: true
- afi: ipv4
neighbor:
- activate: true
address: 10.2.2.2
remote_as: 3549
version: 4
network:
- address: 10.3.3.3
mask: 255.255.255.252
vrf: somevrf

Answer 1

Given the data
address_family:
- afi: ipv4
neighbor:
- activate: true
address: 10.1.1.1
nexthop_self:
set: true
route_maps:
- name: BGP_TO_EC
out: true
- afi: ipv4
neighbor:
- activate: true
address: 10.2.2.2
remote_as: 3549
version: 4
network:
- address: 10.3.3.3
mask: 255.255.255.252
vrf: somevrf
Simplify the data a bit. Put the below declarations into the vars as appropriate
neighbors_raw: "{{ address_family|json_query(nr_query) }}"
nr_query: "[].neighbor[].{address: address, names: route_maps[].name}"
gives
neighbors_raw:
- address: 10.1.1.1
names:
- BGP_TO_EC
- address: 10.2.2.2
names: null
Replace the null with an empty list
- set_fact:
neighbors_list: "{{ neighbors_list|d([]) +
[item|combine({'names': item.names|
ternary(item.names, [])})] }}"
loop: "{{ neighbors_raw }}"
gives
neighbors_list:
- address: 10.1.1.1
names:
- BGP_TO_EC
- address: 10.2.2.2
names: []
Now, you can select the address
- debug:
msg: "{{ neighbors_list|selectattr('names', 'contains', 'BGP_TO_EC')|
map(attribute='address')|list }}"
gives a list because, generally, there might be more selected items
msg:
- 10.1.1.1
You might want to select the first one
- debug:
msg: "{{ neighbors_list|selectattr('names', 'contains', 'BGP_TO_EC')|
map(attribute='address')|first }}"
gives
msg: 10.1.1.1