Using functions inside functions in Puppet 4

[Alessandro Franceschi]

Hi all,

sorry to bother, I should probably search around better but I'm quite confident that I can find here a quick solution.

I've this issue: https://github.com/example42/puppi/issues/123 in a function which tries to use the hiera function as follows:

value = function_hiera(["#{module_name}_#{var_name}", ''])

The error message comes from the 3.x API  hiera class in lib/parser/functions/

Error: Evaluation Error: Error while evaluating a Function Call, hiera() has been converted to 4x API

Wha's the syntax to use an API4 function inside a function?

Maybe should I move the function in my module from lib/puppet/parser/functions to lib/puppet/functions and edit something?

Thanks * for any help

al

[Henrik Lindberg]

If you change your function to use the 4.x API then it can call any
function (3.x or 4.x) using the method call_function. This works from
3.7.5 (earlier version had a problem in calling a 3.x function from 4.x
- see https://tickets.puppetlabs.com/browse/PUP-3548).

For the 4.x function API see the language specification.

You can support both 3.x. and 4.x by just adding a 4.x function with the
same name. 4.x. functions have higher precedence when using future
parser (and 4.x. functions are not visible at all when not using future
parser).

If you really do not want to migrate the function to the 4.x. API then
you could write a utility class to perform the call - the logic to do
this is is here:
https://github.com/puppetlabs/puppet/blob/master/lib/puppet/pops/evaluator/runtime3_support.rb#L234

Regards
- henrik

> Thanks * for any help
> al
>

> --
> You received this message because you are subscribed to the Google
> Groups "Puppet Developers" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to puppet-dev+...@googlegroups.com
> <mailto:puppet-dev+...@googlegroups.com>.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/puppet-dev/d6e542ff-854f-4b46-a568-96f418586af5%40googlegroups.com
> <https://groups.google.com/d/msgid/puppet-dev/d6e542ff-854f-4b46-a568-96f418586af5%40googlegroups.com?utm_medium=email&utm_source=footer>.
> For more options, visit https://groups.google.com/d/optout.


--

Visit my Blog "Puppet on the Edge"
http://puppet-on-the-edge.blogspot.se/

[Alessandro Franceschi]

Thank you for the useful info, going to dive into this, looks quite powerful 

> <mailto:puppet-dev+unsub...@googlegroups.com>.

[Henrik Lindberg]

On 2015-18-05 20:54, Alessandro Franceschi wrote:
> Thank you for the useful info, going to dive into this, looks quite
> powerful
>

I suppose you found the specification of the API:
https://github.com/puppetlabs/puppet-specifications/blob/master/language/func-api.md

Regards
- henrik

> On Thursday, May 14, 2015 at 1:51:49 PM UTC+2, henrik lindberg wrote:
>
> On 2015-14-05 12:58, Alessandro Franceschi wrote:
> > Hi all,
> > sorry to bother, I should probably search around better but I'm
> quite
> > confident that I can find here a quick solution.
> >

> > I've this issue: https://github..com/example42/puppi/issues/123

> <https://github.com/example42/puppi/issues/123> in a
> > function which tries to use the hiera function as follows:
> >
> > value = function_hiera(["#{module_name}_#{var_name}", ''])
> >
> >
> > The error message comes from the 3.x API hiera class in
> > lib/parser/functions/
> >
> > |Error: Evaluation Error: Error while evaluating a Function Call,
> hiera() has been converted to 4x API|
> >
> >
> > Wha's the syntax to use an API4 function inside a function?
> > Maybe should I move the function in my module from
> > lib/puppet/parser/functions to lib/puppet/functions and edit
> something?
>
> If you change your function to use the 4.x API then it can call any
> function (3.x or 4.x) using the method call_function. This works from
> 3.7.5 (earlier version had a problem in calling a 3.x function from 4.x
> - see https://tickets.puppetlabs.com/browse/PUP-3548

> <https://tickets.puppetlabs.com/browse/PUP-3548>).

>
> For the 4.x function API see the language specification.
>
> You can support both 3.x. and 4.x by just adding a 4.x function with
> the
> same name. 4.x. functions have higher precedence when using future
> parser (and 4.x. functions are not visible at all when not using future
> parser).
>
> If you really do not want to migrate the function to the 4.x. API then
> you could write a utility class to perform the call - the logic to do
> this is is here:
> https://github.com/puppetlabs/puppet/blob/master/lib/puppet/pops/evaluator/runtime3_support.rb#L234
> <https://github.com/puppetlabs/puppet/blob/master/lib/puppet/pops/evaluator/runtime3_support.rb#L234>
>
>
> Regards
> - henrik
>
> > Thanks * for any help
> > al
> >
> > --
> > You received this message because you are subscribed to the Google
> > Groups "Puppet Developers" group.
> > To unsubscribe from this group and stop receiving emails from it,
> send

> > an email to puppet-dev+...@googlegroups.com <javascript:>
> > <mailto:puppet-dev+...@googlegroups.com <javascript:>>.

> > To view this discussion on the web visit
> >
> https://groups.google.com/d/msgid/puppet-dev/d6e542ff-854f-4b46-a568-96f418586af5%40googlegroups.com
> <https://groups.google.com/d/msgid/puppet-dev/d6e542ff-854f-4b46-a568-96f418586af5%40googlegroups.com>
>
> >

> <https://groups.google.com/d/msgid/puppet-dev/d6e542ff-854f-4b46-a568-96f418586af5%40googlegroups.com?utm_medium=email&utm_source=footer

> <https://groups.google.com/d/msgid/puppet-dev/d6e542ff-854f-4b46-a568-96f418586af5%40googlegroups.com?utm_medium=email&utm_source=footer>>.
>
> > For more options, visit https://groups.google.com/d/optout

> <https://groups.google.com/d/optout>.

>
>
> --
>
> Visit my Blog "Puppet on the Edge"
> http://puppet-on-the-edge.blogspot.se/

> <http://puppet-on-the-edge.blogspot.se/>

>
> --
> You received this message because you are subscribed to the Google
> Groups "Puppet Developers" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to puppet-dev+...@googlegroups.com

> <mailto:puppet-dev+...@googlegroups.com>.

> To view this discussion on the web visit

> https://groups.google.com/d/msgid/puppet-dev/e5c6cfed-7a1e-40cd-9fc0-d711ffe559cd%40googlegroups.com
> <https://groups.google.com/d/msgid/puppet-dev/e5c6cfed-7a1e-40cd-9fc0-d711ffe559cd%40googlegroups.com?utm_medium=email&utm_source=footer>.