How to define a base_dir var so you can use {{ base_dir }}/playbooks etc?

[Patrick Laimbock]

Hi,

Ansible 2.1.1.0.

Situation: Tim and Bob both deploy servers. Tim checks out the central
ansible git repo to /home/tim/ansible while Bob checks it out to
/home/bob/ansible. No special ansible.cfg is used by either.

Problem: paths differ (/home/tim/ansible vs /home/bob/ansible) so you
can not use static paths in the playbooks etc.

Question: how do you solve that? How do you specify something like a
base_dir variable which is read early on so that all static paths can be
replaced.

<example based on Google findings which I could not make work>

$ grep base_dir /home/tim/ansible/inventory/group_vars/all
base_dir: "{{ lookup('pipe', 'git rev-parse --show-toplevel') }}"

In Tim's case base_dir should be "/home/tim/ansible".

$ cat /home/tim/ansible/vars/global_vars.yml

roles: "{{ base_dir}}/roles"
handlersdir: "{{ base_dir }}/handlers"
tasksdir: "{{ base_dir }}/tasks"
playbooksdir: "{{ base_dir }}/playbooks"
includedir: "{{ base_dir }}/playbooks/include"
manualdir: "{{ base_dir }}/playbooks/manual"
varsdir: "{{ base_dir }}/vars"


$ cat /home/tim/ansible/playbooks/groups/dns

- name: setup dns servers
hosts: dns
user: root
gather_facts: True

vars_files:
- "{{ base_dir }}/vars/global_vars.yml


roles:
- base
- dns



TIA,
Patrick

[Kai Stian Olstad]

On 01.08.2016 18:56, Patrick Laimbock wrote:
> Hi,
>
> Ansible 2.1.1.0.
>
> Situation: Tim and Bob both deploy servers. Tim checks out the central
> ansible git repo to /home/tim/ansible while Bob checks it out to
> /home/bob/ansible. No special ansible.cfg is used by either.

This is a very common way to do it.
You can also put the ansible.cfg in this folder so everybody shares the
same ansible.cfg.

> Problem: paths differ (/home/tim/ansible vs /home/bob/ansible) so you
> can not use static paths in the playbooks etc.

This is not a problem you always use relative paths and not
absolute(static) path.

> Question: how do you solve that? How do you specify something like a
> base_dir variable which is read early on so that all static paths can
> be replaced.

Relative path and Ansible has a directory layout that it understand, I
recommend reading this page that explain the concept.
https://docs.ansible.com/ansible/playbooks_best_practices.html

So when you run ansible or ansible-playbook Tim and Bob will always run
them from within ~/ansible

> <example based on Google findings which I could not make work>
>
> $ grep base_dir /home/tim/ansible/inventory/group_vars/all
> base_dir: "{{ lookup('pipe', 'git rev-parse --show-toplevel') }}"
>
> In Tim's case base_dir should be "/home/tim/ansible".
>
> $ cat /home/tim/ansible/vars/global_vars.yml
>
> roles: "{{ base_dir}}/roles"
> handlersdir: "{{ base_dir }}/handlers"
> tasksdir: "{{ base_dir }}/tasks"
> playbooksdir: "{{ base_dir }}/playbooks"
> includedir: "{{ base_dir }}/playbooks/include"
> manualdir: "{{ base_dir }}/playbooks/manual"
> varsdir: "{{ base_dir }}/vars"
>
>
> $ cat /home/tim/ansible/playbooks/groups/dns
>
> - name: setup dns servers
> hosts: dns
> user: root
> gather_facts: True
>
> vars_files:
> - "{{ base_dir }}/vars/global_vars.yml
>
>
> roles:
> - base
> - dns

It looks like a very strange concept, I do recommend picking up a
Ansible book to get basic knowledge of how Ansible works.

--
Kai Stian Olstad

[Patrick Laimbock]

Hi Kai,

Thank you for your feedback.

On 03-08-16 09:44, Kai Stian Olstad wrote:
> On 01.08.2016 18:56, Patrick Laimbock wrote:
>> Hi,
>>
>> Ansible 2.1.1.0.
>>
>> Situation: Tim and Bob both deploy servers. Tim checks out the central
>> ansible git repo to /home/tim/ansible while Bob checks it out to
>> /home/bob/ansible. No special ansible.cfg is used by either.
>
> This is a very common way to do it.
> You can also put the ansible.cfg in this folder so everybody shares the
> same ansible.cfg.

Got it.

>> Problem: paths differ (/home/tim/ansible vs /home/bob/ansible) so you
>> can not use static paths in the playbooks etc.
>
> This is not a problem you always use relative paths and not
> absolute(static) path.

Great.

>> Question: how do you solve that? How do you specify something like a
>> base_dir variable which is read early on so that all static paths can
>> be replaced.
>
> Relative path and Ansible has a directory layout that it understand, I
> recommend reading this page that explain the concept.
> https://docs.ansible.com/ansible/playbooks_best_practices.html

Will read that.

> So when you run ansible or ansible-playbook Tim and Bob will always run
> them from within ~/ansible
>

[snip]

>
> It looks like a very strange concept, I do recommend picking up a
> Ansible book to get basic knowledge of how Ansible works.

The concept is sorta used by the Fedora Infrastructure team. Looking at
their setup I wondered about defining paths via vars hence my question
to the list.

Thanks again for your help!

Best,
Patrick