Code Using GraphQL

(def schema "type QueryRoot {
    hello: String
  }")
 
(defn resolver-fn [type-name field-name]
  (get-in {"QueryRoot" {"hello" (fn [context parent & rest]
                              "Hello world!")}}
          [type-name field-name]))
 
(require '[graphql-clj.executor :as executor])
 
(executor/execute nil schema resolver-fn "{ hello }")

(require '[alumbra.core :as alumbra]
         '[claro.data :as data])
 
(def schema
  "type Person { name: String!, friends: [Person!]! }
   type QueryRoot { person(id: ID!): Person, me: Person! }
   schema { query: QueryRoot }")
 
(defrecord Person [id]
  data/Resolvable
  (resolve! [_ _]
    {:name    (str "Person #" id)
     :friends (map ->Person  (range (inc id) (+ id 3)))}))
 
(def QueryRoot
  {:person (map->Person {})
   :me     (map->Person {:id 0})})
 
(def app
  (alumbra/handler
    {:schema schema
     :query  QueryRoot}))
 
(defonce my-graphql-server
  (aleph.http/start-server #'app {:port 3000}))

$ curl -XPOST "http://0:3000" -H'Content-Type: application/json' -d'{
  "query": "{ me { name, friends { name } } }"
}'
{"data":{"me":{"name":"Person #0","friends":[{"name":"Person #1"},{"name":"Person #2"}]}}}