How can I make a rails model searchable by the user?
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I'm trying to expose a search feature in rails.  I want a user to be able to enter a string like `name:"john" color:"blue"` and get a list of ActiveRecord objects for some model that have a name attribute containing `john` and a color attribute containing `blue`.  I'd also like them to be able to use `and` and `or` and parentheses e.g. `name:"john" or color:"blue"` or `(name:"john" color:"blue") or name:"bill"`.  Ideally they could also use things like `age<20` where age is an numeric field.  Is there a rails plugin that does this.  I've was looking briefly at sphinx and ferret both of which seem to create an api for this but it was unclear whether they provided a clear text based option or if I would need to parse the search strings myself.