Jira (PUP-1968) Duplicate resources can make re-usable Forge modules difficult

[Felix Frank (JIRA)]

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Felix Frank commented on an issue   Re: Duplicate resources can make re-usable Forge modules difficult Yes. Constraints aim to provide a means to express a need of a module for Puppet to manage a "foreign" resource in a certain fashion. (By foreign I mean that the module does not strictly "own" this resource.) Common workarounds currently include the antipattern of if !defined(Resource['foo']) { resource { 'foo' => ... } } and use of the ensure_resource function from the stdlib module, to much the same effect. Drawbacks of those include incompatibility with each other collisions with plain declarations of the same resource in other places in the manifest... ...and evaluation order dependency that obfuscates these problems possible contradictions or subtle parameter loss in the case of defined Constraints allow a module to declare its needs without accepting the risk of duplicate declarations. Modules will become somewhat less self-contained, because the user will have to use some means to declare the constrained resources herself, either plainly in her own manifest or by including another module that does manage the resource in question. We have no way to work around this limitation. The user will at least receive a clear error message indicating the problem. I opened PUP-2297 to track our efforts to deprecate the defined function in the long run. Add Comment   Puppet / PUP-1968 Duplicate resources can make re-usable Forge modules difficult [EDIT] Re-working this description based on feedback in comment #7. User installs module A to provide a web application. User installs module B to provide a database server. Both module A and module B declare a package resource for foo. User declares classes from both module A and B on the same node. User receives duplicate resource decl... This message was sent by Atlassian JIRA (v6.1.4#6159-sha1:44eaede) -- You received this message because you are subscribed to the Google Groups "Puppet Bugs" group. To unsubscribe from this group and stop receiving emails from it, send an email to puppet-bugs+unsubscr...@googlegroups.com. To post to this group, send email to puppet-bugs@googlegroups.com. Visit this group at http://groups.google.com/group/puppet-bugs. For more options, visit https://groups.google.com/d/optout.