1. Local development: Requires docker, node/npm
2. Browser based: Requires no installation, except a Heroku account

Glitch: https://glitch.com/~transparent-book-j4rrqo19xb

HASURA_GRAPHQL_ADMIN_SECRET: secret

HASURA_GRAPHQL_JWT_SECRET: {"type": "HS256", "key": "myjwtsecretkey111111111111111111111111111111111"}

Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyLCJodHRwczovL2hhc3VyYS5pby9qd3QvY2xhaW1zIjp7IngtaGFzdXJhLWFsbG93ZWQtcm9sZXMiOlsidXNlciJdLCJ4LWhhc3VyYS1kZWZhdWx0LXJvbGUiOiJ1c2VyIiwieC1oYXN1cmEtdXNlci1pZCI6IjEifX0.GuJT4DlW4NCN0T8ffzvqFmDjLUUk1JBhHkamCfI81Tc

type Mutation {
  placeOrder (
    restaurant_id: String!
    items: [OrderItem]
  ): OrderResult
}

input OrderItem {
  item_id : Int
  quantity : Int
}

type OrderResult {
  order_id : String
}

mutation MyMutation {
  placeOrder(restaurant_id: "r1", items: [{item_id: 1, quantity:2}, {item_id:2, quantity:1}]) {
    order_id
  }
}