How to evaluate a yaml key using jinja and then evaluate its value using jinja in .j2 file using ansible?

Q: "evaluate the dev_db_password ... while ansible templates secret.j2. Is there a way to achieve this in the same line by modifying dbpassword: ... ?"

A: Yes. There is. Try lookup plugin vars. See ansible-doc -t lookup vars

dbpassword: "{{'{{'}} {{ lookup('vars', namespace + '_db_password') }} {{'}}'}}"

For example, the template

shell> cat secret.j2stringData:  consoleadminpassword: "{{'{{'}} {{ lookup('vars', namespace + '_console_password') }} {{'}}'}}"  consolenonadminpassword: "{{'{{'}} {{ lookup('vars', namespace + '_console_password') }} {{'}}'}}"  dbpassword: "{{'{{'}} {{ lookup('vars', namespace + '_db_password') }} {{'}}'}}"

and the playbook

- hosts: localhost  tasks:    - template:        src: secret.j2        dest: secret.yml      vars:        namespace: dev        dev_console_password: passwd_console        dev_db_password: passwd_db

give

shell> cat secret.yml stringData:  consoleadminpassword: "{{ passwd_console }}"  consolenonadminpassword: "{{ passwd_console }}"  dbpassword: "{{ passwd_db }}"

If you don't need the next evaluation of the variables (passwords) in the dictionary the template below

shell> cat secret.j2stringData:  consoleadminpassword: {{ lookup('vars', namespace + '_console_password') }}  consolenonadminpassword: {{ lookup('vars', namespace + '_console_password') }}  dbpassword: {{ lookup('vars', namespace + '_db_password') }}

will give

shell> cat secret.yml stringData:  consoleadminpassword: passwd_console  consolenonadminpassword: passwd_console  dbpassword: passwd_db

If you put the passwords into an encrypted file

shell> cat dev.yml dev_console_password: passwd_consoledev_db_password: passwd_db

shell> ansible-vault encrypt dev.ymlEncryption successful

shell> cat dev.yml$ANSIBLE_VAULT;1.1;AES25630663636653963333864346339303034356463356234383035363561356365376130396465323736...

the playbook will give the same results

- hosts: localhost  vars:    namespace: dev  tasks:    - include_vars: "{{ namespace }}.yml"    - template:        src: secret.j2        dest: secret.yml