Ruby on Rails User Control

I want to develop some kind of user control solution in Rails, so then that control can be easily added to Ruby On Rai开发者_如何学JAVAls sites. For example, lets say, i want to create some chat user control with its own database,views,controllers, so then that chat control can be added to Ruby On Rails sites.

Is this possible? And if yes, what should i learn for that(plugins,gems?)

Thanks in advance

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You want to build an Engine.