I think groovy and grails are not bad choices, language is dynamic and what I have read about grails is it is a good framework but I think Django is still more preferable. Ecosystem of Django is bigger than Grails. If you look at github grails have 190 contributor and 1,881 stars and Django have 1,256 contributor 21,186 stars.Although you can interop with Java in groovy python is called glue language. Also similar comparison valid for groovy and python ecosystem. I used ElasticSearch (excellent Java project) for full-text search in jeviz.com and there is a official python package for it.