Re^2: common non-explicit dependencies besides LWP::Protocol::https ?

Hmmm... if the OP says that the absence of this module caused “one of our products to break in the field,” maybe that dependency isn’t so “optional,” after all.

I didn’t even know that dependencies could be optional. There certainly isn’t anything intuitive about that idea, at least to me. Out of curiosity, how do CPAN-authors determine that such a status should be assigned? Can it be overridden? Can dependency-checking tools be instructed to include these “optionals” in their scans?

It sure does sound like the mechanism failed the OP and at least one of his customers. So, what needs to be done about this?

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Re^3: common non-explicit dependencies besides LWP::Protocol::https ? by RonW (Parson) on Jul 09, 2015 at 18:34 UTC
I didn’t even know that dependencies could be optional. There certainly isn’t anything intuitive about that idea, at least to me. Arguably, supporting HTTPS can, as of recently, be considered required. So, in the specific case of LWP::Protocol::https, perhaps that should now be required. As for "optional features" in general, perhaps a better way of handling those? I suppose one could argue that optional feature "bar" of module "Foo" should be used via module "Foo::Bar". but, going back to the OP's use of LWP, would you really want to have to call different "get" methods for different URL schemas? Or would you rather one "get" that looks at the "https:" or "ftp:" at the front of the URL and figure out which protocol to use? I suggest that, as an option, modules devs be able to specify "additional dependencies" as a hash of lists mapping "optional features" to the additional modules required to support said optional features. I'm not sure how best to to handle such options during module install, but having a feature/requirement map available will help with managing installed modules.	[reply]

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Re^3: common non-explicit dependencies besides LWP::Protocol::https ?
by RonW (Parson) on Jul 09, 2015 at 18:34 UTC

I didn’t even know that dependencies could be optional. There certainly isn’t anything intuitive about that idea, at least to me.

Arguably, supporting HTTPS can, as of recently, be considered required. So, in the specific case of LWP::Protocol::https, perhaps that should now be required.

As for "optional features" in general, perhaps a better way of handling those? I suppose one could argue that optional feature "bar" of module "Foo" should be used via module "Foo::Bar". but, going back to the OP's use of LWP, would you really want to have to call different "get" methods for different URL schemas? Or would you rather one "get" that looks at the "https:" or "ftp:" at the front of the URL and figure out which protocol to use?

I suggest that, as an option, modules devs be able to specify "additional dependencies" as a hash of lists mapping "optional features" to the additional modules required to support said optional features. I'm not sure how best to to handle such options during module install, but having a feature/requirement map available will help with managing installed modules.

[reply]