Does graphql allow conditional execution of a step in a mutation?
<p>Since you can have multiple steps run sequentially in a mutation, can you have a conditional if statement in graphql so that later steps only run if the result from a previous step meets a condition?</p>

<p>e.g.</p>

<pre><code> mutation upsertLogin($idToken: String!, $email: String!, $username: String!) {

    User(email: $email, username: $username) {
      id
    }

    // only do the next step if no id from from previous step

    createUser(email: $email, username: $username) {
      id
    }

  }
</code></pre>