title: Implement custom logic after the graphql query has been parsed
body: <p>Is there a way to implement custom logic right after the graphql query has been parsed, but before any of the resolvers have executed?</p>
  <p>Given this query schema</p>
  <pre><code>type Query {
    products(...): ProductConnection!
    productByHandle(handle: String!): Product
  }
  </code></pre>
  <p>How can I accomplish the task of logging the <code>info</code> object for the <code>products</code> and <code>productByHandle</code> queries, before their resolvers have had a chance to execute?</p>
  <p>I'm basically looking to &quot;hook up&quot; to an imaginary event like <code>query:parsed</code>, but it doesn't appear to exist. I'm using the <code>express-graphql</code> package.</p>