README

gri-prisma-select

Generate Prisma select object from GraphQL Resolve Info

GraphQL Resolve Info is a data structure that contains information about the execution of a GraphQL query, with this information you can generate Prisma select object which extends the benefits GraphQL provides to clients to your database by only fetching the fields that are needed and as well resolving the GraphQL n+1 query problem with the power of Prisma.

Demo:

// Turn this to a GraphQL query:
const query = /* GraphQL */ `
  {
    user {
      id
      name
      email
      createdAt
      photo
      posts {
        id
        title
        content
        createdAt
        comments {
          id
          content
          createdAt
          author {
            id
            name
            photo
          }
        }
      }
    }
  }
`
// Into this Prisma select object:
const prismaSelect = {
  select: {
    id: true,
    name: true,
    email: true,
    createdAt: true,
    photo: true,
    posts: {
      select: {
        id: true,
        title: true,
        content: true,
        createdAt: true,
        comments: {
          select: {
            id: true,
            content: true,
            createdAt: true,
            author: {
              select: {
                id: true,
                name: true,
                photo: true,
              },
            },
          },
        },
      },
    },
  },
}

Installation

# with npm
npm install @akumzy/gri-prisma-select
# with yarn
yarn add @akumzy/gri-prisma-select
# with pnpm
pnpm add @akumzy/gri-prisma-select

Usage

This can be used in two ways:

As a GraphQL directive
As a function in your GraphQL resolver

Using GraphQL directive:

Add directive to your GraphQL schema

directive @toPrismaSelect on FIELD_DEFINITION
...

import { toPrismaSelectDirectiveTransformer } from "@akumzy/gri-prisma-select"

let schema = makeExecutableSchema({
  typeDefs,
  resolvers,
})
schema = toPrismaSelectDirectiveTransformer(schema, "toPrismaSelect")

and use the directive in your GraphQL schema to indicate which query you want to generate a Prisma select object for. e.g.

directive @toPrismaSelect on FIELD_DEFINITION
type Query {
  posts: [Post!]! @toPrismaSelect
}

and by doing so a property called prismaSelect will be added to your resolver context

async function posts(parent, args, context, info) {
  const prismaSelect = context.prismaSelect
  return await context.prisma.posts.findMany({
    where: {},
    ...prismaSelect,
  })
}

Using in your GraphQL resolver:

All you need to do is to pass the GraphQL resolve info to the function and it will return a Prisma select object.

import { toPrismaSelect } from "@akumzy/gri-prisma-select"

async function posts(parent, args, context, info) {
  const prismaSelect = toPrismaSelect(info)
  return await context.prisma.posts.findMany({
    where: {},
    ...prismaSelect,
  })
}

Notes

For this package to work as expected you need to make sure that your GraphQL schema has same field names as your Prisma model. Also note that you have given absolute power to your client to fetch any field that is available in GraphQL schema and exists in your Prisma model as well, so be careful not to expose any sensitive information fields in your GraphQL schema.

Another issue you'll face will be unkown type for your Prisma return value.

License

mit

Usage no npm install needed!