Nested resolver for graphql & prisma query

Question

Could anyone suggest how to go about creating a nested resolver to show an array of objects that are held in a parent object through graphql.

In this case, my schema.prisma file has two models GiftCard and Transaction where each GiftCard has a ledger (array of transactions):

generator client {
  provider = "prisma-client-js"
}

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

model GiftCard {
 id            Int
 number        String
 ledger        Transaction[]
}

model Transaction {
 id            Int
 value         Decimal
 giftCard      GiftCard? @relation(fields: [giftCardId], references: [id])
 giftCardId    Int?
}

My typedef for graphql:

type Query {
  cards: [GiftCard!]!
  transactions: [Transaction!]!
}

type GiftCard {
  id: ID!
  number: String!
  ledger: [Transaction!]!
}

type Transaction {
    id: ID!
    value: Float!
}

And my resolvers:

export const resolvers = {
  Query: {
    cards: async (parent, args, context) => {
      return context.prisma.GiftCard.findMany();
    },
    vendors: async (parent, args, context) => {
      return context.prisma.Vendor.findMany();
    },
    transactions: async (parent, args, context) => {
      return context.prisma.Transaction.findMany();
    },
  },

    GiftCard: {
      ledger: async (parent, args, context) => {
        //   return transaction associated with gift card here...
          },
    },
};

The query works perfectly from apollo studio if I query Cards or Transaction without the "ledger" field requested.

Any help would be great!

Thankyou.

user_15777237 · Answer

Good news! Buried in the prisma docs I found the solution and it is not a nested resolver. Prisma does not enable mutual relationships by default inside resolvers. You have to force it to include them so my resolver now looks like this and all my transactions are showing in the graphql query:

export const resolvers = {
  Query: {
    cards: async (parent, args, context) => {
      return context.prisma.GiftCard.findMany({
        include: { ledger: true },
      });
    },}

Nested resolver for graphql & prisma query

1 Answers