Our team is working in a e-commerce analytics project and we are planning to use elastic search for storing reviews on products, which will be large raw texts. So that we can do complex searches on reviews. We are new to the elastic search and we learned so many things in short time span. We need some ideas about achieving some requirements like document categorization. In simple, based in the texts in review , we need to find the category of the review .For example if the review is about shipping problems , we need to find out that from review texts and tag it as 'shipping issue'. Is there any plugin in ES for achieving this more reliably?