variables with 'dashes' in them

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1

I’m noticing that variables names (or registers in ansible) that have ‘-’ (dashes) in their names fail to expand when later called. Here’s a simple example playbook that demonstrates:

  • name: run1
    command: whoami
    register: who

  • name: run2
    command: whoami
    register: who-who

  • name: show
    debug: msg=“run1 output= ${who.stdout} run2 output= ${who-who.stdout}”

The output when run with verbose is:

TASK: [show] *********************
ok: [127.0.0.1] => {“msg”: “run1 output= romeotheriault run2 output= ${who-who.stdout}”}

(The same holds true if it’s a variable like ${login.set-cookie})

This is causing me a bit of an issue with the URI module I’m developing, since some of the returned headers have dashes in them. (e.g. set-cookie, content-type).

Before I dig into this too much, is this an issue that can be “fixed” or is this something I’ll need to get my module to work-around, for example by replacing all “dashes” with “underscores” or something like that?

Thanks,

2

We can probably easily fix the template evaluation, though it's
probably done that way as a variable named "foo-bar" is not a valid
Python variable and can't be accessed directly in Jinja2 either.

It could be accessed through hostvars (and can, too, in your case, I imagine).

Generally dash isn't good for variables in most programming languages
either, so maybe registering to it should really be the core error.

I generally think maybe you might want to transmogrify the headers you
get back so they use underscores and not dashes?
Maybe?

3

We can probably easily fix the template evaluation, though it's
probably done that way as a variable named "foo-bar" is not a valid
Python variable and can't be accessed directly in Jinja2 either.

If it's going to work in some places and not others, I'd say it's probably
better to just keep things consistent and "not allow it".

It could be accessed through hostvars (and can, too, in your case, I
imagine).

Generally dash isn't good for variables in most programming languages
either, so maybe registering to it should really be the core error.

Yeah, I think something along those lines would be good. Some kind of
error/warnings certainly would have helped me save some time
troubleshooting it.

I generally think maybe you might want to transmogrify the headers you
get back so they use underscores and not dashes?
Maybe?

I'm perfectly fine with doing this. This is how I'll proceed.

Thanks,