Support current apollo subscriptions

[lorensr]

Sorry for the lack of PR—working in a generated server with lots of other changes! Latest version of apollo-link-ws uses graphql-ws as the protocol, which isn't supported by

"subscriptions-transport-ws": "0.2.6"

HTTP/1.1 400 Bad Request
Connection: close
X-WebSocket-Reject-Reason: Unsupported protocol.

Fix

package.json
-    "subscriptions-transport-ws": "0.2.6"
+    "subscriptions-transport-ws": "^0.9.1"
-    "graphql": "0.7.2",
-    "graphql-server": "^0.3.2",
-    "graphql-server-express": "^0.4.3",
-    "graphql-subscriptions": "0.2.0",
-    "graphql-tools": "^0.8.2",
+    "graphql": "^0.11.7",
+    "graphql-subscriptions": "^0.5.4",
+    "graphql-tag": "^2.5.0",
+    "graphql-tools": "^2.6.1",
+    "apollo-cache-inmemory": "^1.0.0",
+    "apollo-client": "^2.0.1",
+    "apollo-link-http": "^1.1.0",
+    "apollo-server-express": "^1.2.0",

example resolver:

  Subscription: {
    githubStars: {
      subscribe: () => pubsub.asyncIterator('githubStars')
    }
  }

server/index.js:

import { execute, subscribe } from 'graphql'
...
  SubscriptionServer.create(
    {
      schema,
      execute,
      subscribe,
      onConnect: connectionParams =>
        addModelsToContext({ db, githubAPI, pubsub })
    },
    {
      server: websocketServer
    }
  )