gin,appengine,graphql test

gin+GAE+graphql のテスト下記で行けった。

appEngineTestInstance

->instance.NewRequest

gin.Context(request)

context.Set(key value)

```

ins, _ := aetest.NewInstance(nil)
req, _ := ins.NewRequest("", "", nil)

var context *gin.Context
context = &gin.Context{Request: req}
b, _ := json.Marshal(x.y{z: "1"})
context.Set("key", b)

```