Setting become_user conditionally - ansible

Question

I am trying to shutdown databases in a loop, the catch is some databases run as a different user and others just run as oracle. I login as oracle user and run the playbook and if the database is run as oracle user it goes through fine. If it is running as a different user I would like to become that user (oracle user has permissions to do that).
Here is my main playbook:
[oracle#ansctrlsrv.localdomain epd3]$ cat test.yml
---
- hosts: testdrive
tasks:
- set_fact:
db_list: "{{ lookup('file', 'vars/' ~ inventory_hostname ~ '.dblist')|from_yaml }}"
- name: Shutdown running databases
include_tasks: shutdowndb.yml
loop: "{{ db_list }}"
DB list is as follows:
[oracle#ansctrlsrv.localdomain epd3]$ cat vars/dbsrv.localdomain.dblist
- ebs1
- ebs2
- ndb1
[oracle#ansctrlsrv.localdomain epd3]$ cat shutdowndb.yml
---
- debug: msg='Shutting down {{ item }}'
- name: Execute shutdown
shell: id "{{ item }}"
register: shutdown_output
become: "{{ item is search('ebs') | ternary('yes','no') }}"
become_user: "{{ item }}"
- debug: msg="{{ shutdown_output.stdout }}"
[oracle#ansctrlsrv.localdomain epd3]$ cat inventory
[testdrive]
dbsrv.localdomain
[oracle#ansctrlsrv.localdomain epd3]$ ansible-playbook -i inventory test.yml
TASK [Execute shutdown] ***
fatal: [dbsrv1.localdomain]: FAILED! => {"changed": false, "module_stderr": "Shared connection to dbsrv1.localdomain closed.\r\n", "module_stdout": "", "msg": "MODULE FAILURE\nSee stdout/stderr for the exact error", "rc": 1} ...ignoring
I tried this question on another thread but got closed, so trying another hand after realizing a few issues myself such as being unable to run blocks of code with a loop, etc.
Appreciate any help.
Set become user conditionally

Answer 1

Fix the line
shell: id "{{ item }}"
correct syntax (use shell only when necessary)
command: "id {{ item }}"
The playbook below
- hosts: testdrive
tasks:
- set_fact:
db_list: "{{ lookup('file', 'vars/' ~ inventory_hostname ~ '.dblist')|from_yaml }}"
- name: Shutdown running databases
include_tasks: shutdowndb.yml
loop: "{{ db_list }}"
with the included tasks
$ cat shutdowndb.yml
- debug:
msg:
- "shell: {{ 'shutdown.sh ' ~ item }}"
- "become: {{ item is search('ebs')|ternary('yes', 'no') }}"
- "become_user: {{ item }}"
give
"msg": [
"shell: shutdown.sh ebs1",
"become: yes",
"become_user: ebs1"
]
"msg": [
"shell: shutdown.sh ebs2",
"become: yes",
"become_user: ebs2"
]
"msg": [
"shell: shutdown.sh ndb1",
"become: no",
"become_user: ndb1"
]
Q: "Why the command whoami is still giving oracle rather than ebs1?"
A: Short answer: Because become is not set to True.
Debugging
1) Is it possible to become all of the users in db_list? Yes.
- hosts: test_01
become: no
remote_user: admin
vars:
db_list: ['ebs1', 'ebs2', 'ndb1']
tasks:
- command: whoami
become_user: "{{ item }}"
become: true
register: result
loop: "{{ db_list }}"
- debug:
msg: "{{ result.results|json_query('[].stdout') }}"
give
"msg": [
"ebs1",
"ebs2",
"ndb1"
]
2) Does search and ternary work properly? Yes.
- debug:
msg: "{{ item is search('ebs')|ternary(true, false) }}"
loop: "{{ db_list }}"
gives
"msg": true
"msg": true
"msg": false
3) Does become and become_user work properly?. Yes.
- command: whoami
become_user: "{{ item }}"
become: "{{ item is search('ebs')|ternary(true, false) }}"
register: result
loop: "{{ db_list }}"
- debug:
msg: "{{ result.results|json_query('[].stdout') }}"
give
"msg": [
"ebs1",
"ebs2",
"admin"
]