GraphQL using Java and Springboot

Idea of this sample program is to illustrated GraphQL using Java, Springboot, and MongoDB as data-store. This sample java/maven code is to illustrate GraphQL mutation and query, code must be used only as an example. This example also illustrates GraphiQL for quick testing and experimenting with dynamic query and mutation.

Dependencies

    1) Java 8 or 9
    2) Maven (Preferably  Maven 3.6.0  or latest)
    3) MongoDB Community edition. [ You are required to install mongodb on your laptop/mac. This example uses mongodb as data-store. MongoDB Community edition is available at https://docs.mongodb.com/manual/administration/install-community/ ] 
    4) GraphQL, SpringBoot [ These dependencies will be pulled by maven at build time ]

Build and Test

GraphiQL-UI is available at

    http://localhost:8080/graphiql

1) Add new author (Insert data)

mutation {
  newAuthor(firstName: "Mahatma  M. K. ", lastName: "Gandhi") {
    authorId
    firstName
    lastName
  }
}

Note: Make note of authorId and use it for inserting book record

2) Add new book (Insert data)

mutation {
  newBook(
    title: "Satyagraha in South Africa",
    isbn: "8172290412",
    author: 1) {
      bookId
      title
  }
}

Note: In above example (Inserting book data) we have used "author: 1", instead use correct authorId received from first step (Inserting author data).

3) View all books (Query data)

{
  findAllBooks {
    bookId
    isbn
    title
    pageCount
    author {
      firstName
      lastName
    }
  }
}

4) View books by Ids (Query data)

    {
      query: findAllBooksById(bookIds: [id1, id2]) {
        bookId
        author {
          firstName
          lastName
        }
      }
    }