You're hitting the nail on the head that implementing the resolvers is the hard part when building a GraphQL server! I work at Graphcool (www.graph.cool) and we recently open-sourced a new tool called Prisma that will help you with exactly that part! Our goal with Prisma is to automatically turn any database into a GraphQL API - right now we have connector for MySQL, but we're working on more for Postgres, MongoDB, Neo4j etc... You're then building your application server using GraphQL bindings (read more here: https://blog.graph.cool/reusing-composing-graphql-apis-with-...) which allows to simply delegate incoming queries to the underlying Prisma engine.
Would be curios to hear your opinion on Prisma!
You can try it out here: https://www.prismagraphql.com/docs/quickstart/
You can also check out the 4min demo-video (with TypeScript) I made that explains how it works: https://www.youtube.com/watch?v=20zGexpEitc