Little graph server demo. Apollo server running in an Express app.

Install packages and seed the data:

yarn
node populate.js

The "database" here is just flat JSON files and a simple module to query and modify their data.

yarn start will start an Express server with an Apollo GraphQL server attached. There are no Express routes, but 2 graph routes.

The goal here was to expose two different graphs from a single server, mostly to prove that it could be done. I was also trying to learn how to write resolvers that dealt with mapping, so I could join two (or more) documents into the same query. The "v2" graph was a nice way to add that while still having the basic use case available in "v1".

This only exposes books, which you can query like so:

query {
  books {
    id
    title
    author
  }
}

This exposes book, books, and authors, and joins books and authors together. Here's an extensive query to show how they work:

query {
  books {
    id
    title
    author {
      id
      name
    }
  }

  book(id: "x7174v9cof") {
    title
    author {
      name
    }
  }

  authors {
    id
    name
  }

  author(id: "ls5xcds8ln") {
    id
    name
    books {
      id
      title
      author {
        name
      }
    }
  }
}

You can also use a mutation to add new books and authors. Here's a valid way to use the addBook mutation:

mutation {
  addBook(title: "Ender's Game", author: "mlqnnsc8rq") {
    id
    title
    author {
      id
      name
    }
  }
}

• A Beginner’s Guide to GraphQL
• GraphQL Server Tutorial with Apollo Server and Express

MIT © w33ble