How to override nested variables?

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1

Hi folks,

I created a role with default variables using a nested syntax and not I’d like to override just a few of those attributes in the playbook, but whenever I do it I end up redefining the entire variable na loosing the defaults for the non overrided values.

For example, in role/mysql/defaults/main.yml:

2

There is a variable merging setting, but I prefer being explicit about
having a complex variable, parts of which can be overridden (rather
than magically "doing the right thing").

3

Hi Kahil,

Thanks for the suggestion, but the problem remains. You haven’t override the default value, but instead declared a second flat variable. The problem with this approach is that if do this for every paramet I’ll double the number of used variables. Also I will have to “flatten” them all which in practice would be easier to just flatten the defaults.

But I do wish to have the nested syntax because some of my variables become very confusing when flattening and I also found it better for organization and clarity in the yml.

Still hoping to find a way to do it.

Cheers,

4

“I created a role with default variables using a nested syntax and not I’d like to override just a few of those attributes in the playbook”

There is no problem in doing this.

You can use parameterized roles, include a variable file, use set_fact, or all sorts of things.

Now what you are asking is something different – you should change the hash merge behavior in ansible.cfg.

5

Michael, after reading the ansible.cfg documentation page, I found the parameter you mentioned, together with an warning against it. Since I value the experience from everyone here more than mine, would you care to explain why merging the hashes could be such bad idea?

Thanks again.

ps.: not trying to raise a flame, just like to hear about it.

6

​I'm not sure which warning that is, but I can confirm you I have been
using the merge functionality for a long time, and do not experience any
problems with it.

Of course you have to remember or take into account where you define
(different parts of) those hashes, ​and understand the possible
implications.

Serge

7

The config documentation was suggesting that most people leave it in the standard mode to make sure everybody’s writing playbooks the same way.

That was it.

8

Great! Thanks all for the inputs and help!