GraphQL-spring-boot

Attempt to use GraphQL java library to build GraphQL server using spring boot.MongoDB is used as a storage.

Schema for GraphQL (SDL)

• resources/schema.graphqls contains GraphQL schema defination for query,resolver and types

Application Initialization

• Unit tests runs using gradle clean test
• Make sure you have mongo installed on your machine.App will connect on port 27017 by default.
• Start mongoDB using mongo command.
• Embedded tomcat of spring boot starts using gradle bootRun

Query

• Fetch all blogs : http://localhost:8080/graphql POST Endpoint. Request body format : { "query": "{allBlogs{title}}" }

• It sounds little stupid here to fetch all blogs using POST http method but it is used so we can pass query as a part of request body. We can change is to GET and pass actual query as query param.

• Resonse that you will get is : { "allBlogs": [ { "title": "REST in peace.GraphQL live long" }, { "title": "Kotlin for Android" } ] }

• Lets add one more parameter to request body i.e content { "query": "{allBlogs{title content}}" }

• Response : { "allBlogs": [ { "title": "REST in peace.GraphQL live long", "content": "GraphQL dominating now days" }, { "title": "Kotlin for Android", "content": "how useful is kotlin for android dev" } ] }

Mutation aka POST

• GraphQL provides feature of Mutation which let us create new enitity.

• Create Blog: http:/localhost:8080/graphql. Request Body: { "query": "mutation createBlog {createBlog(title:\"hello\",content:\"world\") {title content}}" }

• Response: { "createBlog": { "title": "hello", "content": "world" } }

• If you now again Query all blogs response would be { "allBlogs": [ { "title": "REST in peace.GraphQL live long", "content": "GraphQL dominating now days" }, { "title": "Kotlin for Android", "content": "how useful is kotlin for android dev" }, { "title": "hello", "content": "world" } ] }