Spring Boot with GraphQL Query, using apigen plugin Example

Requirements

You'll need

• Java 8.
• Meven 3.X.
• lombok plugin.

Frameworks used:

• Graphql for java
• Graphql-apigen
• Graphql-Spring-Boot

Book Store

• /book is the REST resource which can fetch Books information
• DataFetchers are Interfaces for RuntimeWiring of GraphQL with JpaRepository

Model configuration

• To create a rest service on graphQl using the plugin - apigen to facilitate the implementation of the model in graphql and the other functionalities for queries or mutations of the objects.

  type Book @java(package:"com.graphql.schema.library.book") {
      id: String! #Identifier of Book
      isn: String! #Isn of Book
      title: String! #Tittle of Book
      publishedDate: String! #published Date of Book
  }
  

  • Definition of the book object with its corresponding attributes.

  # Root query
  type QueryRoot @java(package:"com.graphql.schema.library.root.query") {
      books(id: String!): [Book]
      book(id: String!): Book
  }
  

  • Definition of the queries that can be made about the object.

  # Entry object to group the properties of a book and create it
  input InputCreateBook @java(package:"com.graphql.schema.library.mutation") {
     isn: String!
     title: String!
     publishedDate: String!
  }   
  

  • Object definition with which new book type objects can be created.

  # Entry object to group the properties of a book and update it
  input InputUpdateBook @java(package:"com.graphql.schema.library.mutation") {
      id: String!
      isn: String!
      title: String
      publishedDate: String
  }
  

  • Object definition with which you can update existing objects of type book

  # Operations on books
  type Mutation @java(package:"com.graphql.schema.library.mutation") {
      createBook(book: InputCreateBook!): Book
      deleteBook(id: String!): Boolean
      updateBook(book: InputUpdateBook!): Book
  }
  

  • Definition of operations with which the state of a book type object can be modified

  Note: With the annotation @java(package: "") we indicate to the apigen plugin where we want it to generate the sources.

Use mode

• Accessing the url http://localhost:8090/book you will see a view like the following

  

Query

• Usage for books

{
   books {
     id
     isn
     title
     publishedDate
   }
 }

• Result

{
   "data": {
     "books": [
       {
         "id": "4028808d680b062c01680b06380c0000",
         "isn": "4bbce612-3f4c-4d44-a8e3-151b35f23071",
         "title": "Java",
         "publishedDate": "2019-01-01"
       },
       {
         "id": "4028808d680b062c01680b06383f0001",
         "isn": "453be0f2-789f-49cd-b15e-5f2ed5f74754",
         "title": "Python",
         "publishedDate": "2019-01-01"
       },
       {
         "id": "4028808d680b062c01680b0638400002",
         "isn": "7b241943-7823-4b89-a304-cec9d79680dd",
         "title": "PHP",
         "publishedDate": "2019-01-01"
       },
       {
         "id": "4028808d680b062c01680b0638410003",
         "isn": "13f57848-6afb-4886-a90c-c7f70804021a",
         "title": "C#",
         "publishedDate": "2019-01-01"
       },
       {
         "id": "4028808d680b062c01680b0638420004",
         "isn": "ef2ef914-30e1-46f8-b4c4-cd4e709fa5f9",
         "title": "C++",
         "publishedDate": "2019-01-01"
       }
     ]
   }
}

• Usage for book

{
   book(id: "4028808d680ae16901680ae174c90000") {
     id,
     title,
     publishedDate
   }
}

• Result

{
   "data": {
     "book": {
       "id": "4028808d680b062c01680b06380c0000",
       "title": "Java",
       "publishedDate": "2019-01-01"
     }
   }
}

• Combination of both book and books

{
   book(id: "4028808d680ae16901680ae174c90000"){
       id,
       title,
       publishedDate
     },
     books{
       id,
       isn
     }
}

• Result

{
   "data": {
     "book": {
       "id": "4028808d680b062c01680b06380c0000",
       "title": "Java",
       "publishedDate": "2019-01-01"
     },
     "books": [
       {
         "id": "4028808d680b062c01680b06380c0000",
         "isn": "4bbce612-3f4c-4d44-a8e3-151b35f23071"
       },
       {
         "id": "4028808d680b062c01680b06383f0001",
         "isn": "453be0f2-789f-49cd-b15e-5f2ed5f74754"
       },
       {
         "id": "4028808d680b062c01680b0638400002",
         "isn": "7b241943-7823-4b89-a304-cec9d79680dd"
       },
       {
         "id": "4028808d680b062c01680b0638410003",
         "isn": "13f57848-6afb-4886-a90c-c7f70804021a"
       },
       {
         "id": "4028808d680b062c01680b0638420004",
         "isn": "ef2ef914-30e1-46f8-b4c4-cd4e709fa5f9"
       }
     ]
   }
}

Mutations

• Usage for createBook

mutation($book: InputCreateBook) {
   createBook(book: $book) {
     id
     isn
     title
     publishedDate
   }
 }

• Variables

{
  "book": {
    "isn": "4bbce612-3f4c-4d44-a8e3-151b35f236754",
    "title": "R",
    "publishedDate": "2019-01-02"
  }
}

• Usage for updateBook

mutation($book: InputUpdateBook) {
   createBook(book: $book) { 
 		title
   }
 }

• Variables

{
  "book": {
    "title": "Node Developer"
  }
}

• Note: As shown in the example, graphql allows you to create and query the object created in the same request.

• Usage for deleteBook

mutation ($id: String) {
   deleteBook(id: $id)
 }

• Variables

{
  "id": "4028808d680b568e01680b5698b60000"
}