express-graphql-vitabu

This is an Express.js application that serves a GraphQL API for querying books and authors. It uses the express-graphql middleware to create a GraphQL server.

Here's how you can create a similar app and have fun with it:

1. Import necessary dependencies:

   • express: This imports the Express.js framework to create a web server.
   • graphqlHTTP: This imports the express-graphql middleware for handling GraphQL requests.
   • Various GraphQL related modules are imported, including types and objects for defining the schema.

2. Define sample data:

   • Two arrays, authors and books, are defined to serve as sample data for authors and books.

3. Define GraphQL Types:

   • BookType: This represents the GraphQL type for books. It has fields for id, title, and author, where author is an object of type AuthorType. The resolve function is used to fetch the author information for a given book based on the authorId.
   • AuthorType: This represents the GraphQL type for authors. It has fields for id, name, and books, where books is a list of BookType. The resolve function is used to fetch all books associated with a given author.

4. Define Root Query:

   • RootQueryType: This represents the root query type for the GraphQL schema. It defines the following query fields:
     • book: Retrieves a single book by its id.
     • books: Retrieves a list of all books.
     • authors: Retrieves a list of all authors.
     • author: Retrieves a single author by their id.

5. Create GraphQL Schema:

   • The schema is created using GraphQLSchema, with RootQueryType as the query root.

6. Set up Express.js Server:

   • The Express.js app is initialized using express().
   • The GraphQL middleware is mounted at the /graphql endpoint using app.use(). It uses the schema defined earlier and enables the GraphiQL interface for easy GraphQL querying during development.

7. Start the Server:

   • The Express.js server listens on port 3000.

PS: "VITABU" means BOOKS in Swahili!!