README.md

Spring Boot Fundamentals

GraphQL

GraphQL offers greater flexibility in the response returned than REST.

• Allows client to specify the exact data needed
• Aggregation of data from multiple sources
• No longer required to call multiple APIs for needed data
• GraphQL offers maximum efficiency and flexibility

Example

Query:

{
  findAllApplications
  {
    id
    owner
  }
}

Response:

{
  "data": {
    "findAllAplications": [
      {
        "id": "1",
        "owner": "Kesha"
      },
      {
        "id": "2",
        "owner": "Jane"
      }
    ]
  }
}

Dependencies

<dependency>
    <groupId>com.graphql-java</groupId>
    <artifactId>graphql-spring-boot-starter</artifactId>
</dependency>
<dependency>
    <groupId>com.graphql-java</groupId>
    <artifactId>graphql-java-tools</artifactId>
</dependency>

Schema

• Defines data points offered via an API
• Data types and relationships
• Operations available
• Graphql-java-tools parses schemas ending in .graphqls

Graphqls

• There can only be one root Query
• There can only be one Mutation type

GraphIQL

A useful tool to test mutations and queries against a GraphQL server.

<dependency>
    <groupId>com.graphql-java</groupId>
    <artifactId>graphiql-spring-boot-starter</artifactId>
</dependency>

http://localhost:8080/graphiql