Proposal: Module Relationships

After reading dman's Open Letter I started to think about how module management on d.o can be improved. Not just to identify duplicated modules, but also regarding dependencies and incompatibilities.

With the absolutely fantastic growth in the number of contributed modules for Drupal it is quickly becoming more difficult to navigate through them, both to find a module that suites the needs and information about if it may create problems with modules already installed. Often this require quite a bit of research through various issue queues, forum threads and so on.

Incompatibility will be a growing issue as the number of modules keeps growing. Sometimes there exists incompatibility between two modules that are completely unrelated, which are difficult to spot.

Many module maintainers do great work documenting their modules, including listing problems, dependencies and so on.

The problem, as I see it, is that each module is managed individually. If module X improves functionality of module Y, then it generally says so on the project page for module X but not very often of the page for module Y. To get that information on the page of module Y someone needs to take the time to contact the maintainer, create an issue ticket and then hope the maintainer updates the page.

Module Relationships

After thinking a bit I came up with a method that can automate this in one step by simply creating creating Module Relationships.

This is how I propose it will work:

For each project there is a new feature - Create Relationship.

When clicking on this you will see a form where it is possible to select what type of relationship it is. The ones on the top of my head is:

• Depends on - Here it is possible to select one or more modules this module is depended on, both mandatory and optional.
• Improves on - This option will both list modules this module improves feature wise and modules that add features to this module such as when for example Tokens support is in the module.
• Incompatible with - Simply modules that it will conflict with.
• Similar to - Other modules with similar features or duplicated modules. There could even be a link to a page that gives an overview of the similarities and differences.

Depending on the type of relationship the form to fill in will look different. But there has to be versions in there so it is possible to set which version of other modules it is incompatible with and so on.

It should also be possible to add on to each existing relationship so they can be updated when changes to modules are made. Default will be the current official version, but then it should also be possible to see info for older versions since not every site is, or can be, updated for various reasons.

When a relationship is created it will automatically show up on the project page for each module related to.

I can also see some interesting side effects to this.

Looking at Depends on and Improves on they can be used to build a very nice, easy to use and flexible module finder. As the relationships already are there then when looking at for example the CCK module there will be a list of every module that is depending on it.

As it will be possible to set categories etc. for the module it will then be easy to narrow down the CCK modules as well.

For each relationship or sub item to a relationship it should be easy to add links to related pages, tickets and so on that contain related information to it, such as a page/ticket that explains how to fix the incompatibility.

I think that if something like this can be implemented it will have many positive effects. It will be easier to navigate through the thousands of existing modules, it will be easier to quickly find, prevent and/or fix problems such as incompatibilities and so on.

I also believe that this will make it easier for module developers as well. When for example an incompatibility relationship is created then a notification can be emailed to the maintainers of each involved module.

Could this be something you think?