Dictionary keys and global variable namespace clash?

[Jameel Al-Aziz]

I'm not sure if this is a bug or intended behavior.

If I have the following playbook (the database_url variable actually lives in a separate var file):

---
- hosts: all
  vars:
    - environment: development
    - database_url:
        development: mysql://development
        production: mysq://production
    - env_vars:
        environment: "{{ environment }}"
        database_url: "{{ database_url[environment] }}"
  pre_tasks:
    - debug: var=environment
    - debug: var=env_vars

and run it with "ansible-playbook -c local -i localhost, test.yml", I get:

PLAY [all] ********************************************************************


GATHERING FACTS ***************************************************************
ok: [localhost]


TASK: [debug var=environment] *************************************************
ok: [localhost] => {
    "var": {
        "environment": {}
    }
}


TASK: [debug var=env_vars] ****************************************************
ok: [localhost] => {
    "var": {
        "env_vars": {
            "database_url": "{{ database_url[environment] }}",
            "environment": {}
        }
    }
}


PLAY RECAP ********************************************************************
localhost                  : ok=3    changed=0    unreachable=0    failed=0

As you can see, the environment variable and database_url aren't resolved. It seems that the environment key under the env_vars dictionary clobbers the global environment key. I could simply set the value of the environment variable on the environment dictionary key itself (I don't need it to be global), but then the database_url still won't resolve. 

---
- hosts: all
  vars:
    - environment: development
    - database_url:
        development: mysql://development
        production: mysq://production
    - env_vars:
        environment: development
        database_url: "{{ database_url[environment] }}"
  pre_tasks:
    - debug: var=environment
    - debug: var=env_vars

PLAY [all] ********************************************************************


GATHERING FACTS ***************************************************************
ok: [localhost]


TASK: [debug var=environment] *************************************************
ok: [localhost] => {
    "var": {
        "environment": {}
    }
}


TASK: [debug var=env_vars] ****************************************************
ok: [localhost] => {
    "var": {
        "env_vars": {
            "database_url": "{{ database_url[environment] }}",
            "environment": "development"
        }
    }
}


PLAY RECAP ********************************************************************
localhost                  : ok=3    changed=0    unreachable=0    failed=0

However, if I rename the global "environment" variable to "env", it works fine. At a high-level this seems like inconsistent behavior; a dictionary key clobbers a global variable, but then cannot be used as global variable.

I know I could just load a separate var file for each environment, but the issue would still exist where re-using a variable name as a dictionary key would clobber the variable.

[Brian Coca]

environment is a reserved keyword, you should not be using it as a
variable name.



--
Brian Coca

[Jameel Al-Aziz]

Wow. My bad.

Changing it to env makes everything work. Thanks for pointing that out!