How to access duplicate values in a JSON array and set each to a unique variable in ansible? - ansible

Question

I am running an ansible playbook which outputs my information in JSON. This array has a loop that has multiple identical keys with different values. Please see below, I am interested in the "intf_id":
"stdout": [
{
"TABLE_cdp_neighbor_brief_info": {
"ROW_cdp_neighbor_brief_info": [
{
"capability": [
"switch",
"IGMP_cnd_filtering"
],
"device_id": "osw1J15",
"ifindex": "83886080",
"intf_id": "mgmt0",
"platform_id": "cisco WS-C2960X-48TS-LL",
"port_id": "GigabitEthernet0/45",
"ttl": "160"
},
{
"capability": [
"router",
"switch",
"Supports-STP-Dispute"
],
"device_id": "spine01",
"ifindex": "436232192",
"intf_id": "Ethernet1/49",
"platform_id": "N9K-C9508",
"port_id": "Ethernet1/11",
"ttl": "159"
},
{
"capability": [
"router",
"switch",
"Supports-STP-Dispute"
],
"device_id": "spine02",
"ifindex": "436232704",
"intf_id": "Ethernet1/50",
"platform_id": "N9K-C9508",
"port_id": "Ethernet1/11",
"ttl": "127"
},
{
"capability": [
"router",
"switch",
"IGMP_cnd_filtering",
"Supports-STP-Dispute"
],
"device_id": "leaf1J1402",
"ifindex": "436234240",
"intf_id": "Ethernet1/53",
"platform_id": "N9K-C93180YC-EX",
"port_id": "Ethernet1/53",
"ttl": "175"
},
{
"capability": [
"router",
"switch",
"IGMP_cnd_filtering",
"Supports-STP-Dispute"
],
"device_id": "leaf1J1402",
"ifindex": "436234752",
"intf_id": "Ethernet1/54",
"platform_id": "N9K-C93180YC-EX",
"port_id": "Ethernet1/54",
"ttl": "175"
}
]
},
"neigh_count": "5"
}
]
Currently I can access the first iteration of "intf_id" with :
- debug: msg="{{ list.stdout[0].TABLE_cdp_neighbor_brief_info.ROW_cdp_neighbor_brief_info[0].intf_id }}"
I feel like I'm close, but cannot figure out how to get each iteration of "intf_id". I can get subsequent ones by changing ROW_cdp_neighbor_brief_info[0] to [1] or [2], etc. I need to be able to access each key, without knowing how many keys there will be. Each value to the keys also need to be individually callable by subsequent tasks.
1) How do I get ansible to debug each iteration?
2) Depending on the answer to 1, how can I assign a particualr variable to each value? (ie. interface1, interface2, interface3...)

Answer 1

ansible-playbook json_query.yml
tasks:
- name:
debug:
msg: "{{ item }}"
loop: "{{ stdout | json_query('TABLE_cdp_neighbor_brief_info.ROW_cdp_neighbor_brief_info[*].intf_id') }}"
(output abridged)
"msg": "mgmt0"
"msg": "Ethernet1/49"
"msg": "Ethernet1/50"
"msg": "Ethernet1/53"
"msg": "Ethernet1/54"

Answer 2

You can use the filter json_query with jmespath syntax to loop over the various elements intf_id this way
---
- hosts: localhost
gather_facts: no
tasks:
- name: populate router data from json
set_fact:
data: "{{ lookup('file','so-router-info.json') }}"
- name: looping over interfaces
debug:
var: item
loop: "{{ data | json_query('TABLE_cdp_neighbor_brief_info.ROW_cdp_neighbor_brief_info[*].intf_id') }}"
it gives this output
…
TASK [looping over interfaces] ********************************************************************************************************
ok: [localhost] => (item=mgmt0) => {
"item": "mgmt0"
}
ok: [localhost] => (item=Ethernet1/49) => {
"item": "Ethernet1/49"
}
ok: [localhost] => (item=Ethernet1/50) => {
"item": "Ethernet1/50"
…
You can use the site http://jmespath.org/ to tests filters