A sample GraphQL type defintion file

seat-saver.graphql

const {gql} = require('apollo-server');

module.exports =  gql`
    """A custom scalar that returns time data as JavaScript Date object"""
    scalar Date
    scalar Object
    
    enum SeatStatus {
        """The seat is in the process of being released from RESERVED or SOLD status"""
        RELEASING
        """The seat is open for reservation or sale."""
        OPEN
        """The seat is in the process of being reserved."""
        RESERVING
        """The seat has been reserved but not sold."""
        RESERVED
        """The seat is in the process of being sold."""
        SELLING
        """The seat has been sold."""
        SOLD
    }
    
    type Query {
        venues: [Venue]
        venue(id: ID!): Venue
        soldSeats(venueId: ID!): [Seat]
        reservedSeats(venueId: ID!): [Seat]
        openSeats(venueId: ID!):[Seat]
    }
    type Mutation {
        reserveSeat(seat: SeatInput): Seat
        buySeat(seat: SeatInput): Seat
        releaseSeat(seat: SeatInput): Seat
    }

    type Subscription {
        onSeatReserved: SeatEvent
        onSeatSold: SeatEvent
        onSeatReleased: SeatEvent
    }
    """A venue is a organizational unit for seats. For example, a venue can be an arena or an airplane."""
    type Venue {
        id: ID
        name: String
        address: String
        city: String
        state_province: String
        postal_code: String
        country: String
        seats: [Seat]
    }
    
    """A seat in a venue"""
    type Seat {
        id:ID
        number: String!
        section: String!
        status: SeatStatus!
        customer: Customer
    }
    input SeatInput {
        """The system assigned unique identifier of a venue"""
        venueId: ID!
        """The unique seat number"""
        number: String!
        """The customer interested in the seat"""
        customer: CustomerInput!
    }
    
    input CustomerInput {
        firstName: String
        lastName: String
        email: String
    }
    """A customer type known the system uniquely according to email address"""
    type Customer {
        firstName: String
        lastName: String
        email: String
    }

    """ An event that describes activity around a seat. The event is generated by the system and sent as a message in a subscription."""
    type SeatEvent {
        message: String
        venueId: ID
        seatId: ID
        number: String!
        section: String
        status: SeatStatus!
        changeDate: Date
    }
`;