ansible select one value from list

Question

I am writing a ansible playbook. In this Playbook I use the function read_csv to read a csv into a list.

The csv file has this format:

Name;Hostname;fqdn;Typ;IPAddress
aaa_nfs_db;aaa;aaa.domain.tld;db;10.1.1.1
aaa_nfs_log;aaa;aaa.domain.tld;log;10.2.2.2
bbb_nfs_db;bbb;bbb.domain.tld;db;10.3.3.3
bbb_nfs_log;bbb;bbb.domain.tld;log;10.4.4.4

I run the playbook on aaa.domain.tld and I want to assign 10.1.1.1 to one variable and 10.2.2.2 to another variable.

How can I do that?

in awk it looks like this:

$ awk -F";" '$3=="aaa.domain.tld"&&$4=="db"{print $5;}' test.csv
10.1.1.1
$ 

I need the ansible Playbook way to filter the list.

sincerely yours

Mario

Answer 1

Once you load your csv into a variable using the corresponding read_csv module, you can filter and select values inside the list with the usual filtering tools (selectattr, map, ...)

For the demo, I placed your above file in files/example.csv. Then the following playbook.yml:

---
- name: Parse csv and filtering demo
  hosts: localhost
  gather_facts: false

  tasks:
    - name: read in our csv file in a list
      read_csv:
        path: files/example.csv
        delimiter: ;
      register: hosts_info

    - name: Show the entire info we parsed (if running with `-v`)
      debug:
        var: hosts_info.list
        verbosity: 1

    - name: Show ip depending on fqdn and type
      vars:
        ip: >-
          {{
            hosts_info.list
            | selectattr('fqdn', '==', item.fqdn)
            | selectattr('Typ', '==', item.type)
            | map(attribute='IPAddress')
            | list
            | first
          }}
      debug:
        msg: "The ip of {{ item.fqdn }} for type {{ item.type }} is {{ ip }}"
      loop:
        - fqdn: aaa.domain.tld
          type: db
        - fqdn: aaa.domain.tld
          type: log

gives (run with -v to see the intermediate debug)

$ ansible-playbook playbook.yml 

PLAY [Parse csv and filtering demo] ****************************************************************************************************************************************************************************************************

TASK [read in our csv file in a list] **************************************************************************************************************************************************************************************************
ok: [localhost]

TASK [Show the entire info we parsed (if running with `-v`)] ***************************************************************************************************************************************************************************
skipping: [localhost]

TASK [Show ip depending on fqdn and type] **********************************************************************************************************************************************************************************************
ok: [localhost] => (item={'fqdn': 'aaa.domain.tld', 'type': 'db'}) => {
    "msg": "The ip of aaa.domain.tld for type db is 10.1.1.1"
}
ok: [localhost] => (item={'fqdn': 'aaa.domain.tld', 'type': 'log'}) => {
    "msg": "The ip of aaa.domain.tld for type log is 10.2.2.2"
}

PLAY RECAP *****************************************************************************************************************************************************************************************************************************
localhost                  : ok=2    changed=0    unreachable=0    failed=0    skipped=1    rescued=0    ignored=0