Prisma-flat-graphql-generator NPM

Overview

prisma-flat-graphql-generator is a prisma generator designed to automatically generate GraphQL schema and resolvers from a Prisma schema. This tool streamlines the process of setting up a GraphQL server by creating a comprehensive structure of resolvers, type definitions, and input types based on your Prisma models. The resolvers are created in such a way that any graphql query will result in a single prisma query to avoid N+1 issues.

Installation

To install, run npm install prisma-flat-graphql-generator

You will also need to install: @paljs/plugins flattens the graphql query into a prisma select format, avoiding N+1 issues. graphql-type-json used by the generated code.

In your Prisma schema file, add the following generator clause:

generator graphql { 
    provider = "prisma-flat-graphql-generator"
}

Usage

First, run prisma generate to run the generator: npx prisma generate
Create a file that will hold the schema:

import { makeExecutableSchema } from "@graphql-tools/schema";
import { PrismaSelect } from '@paljs/plugins';
import { applyMiddleware } from 'graphql-middleware';
import { typeDefs, resolvers } from './Types';

const middleware = async (resolve: any, root: any, args: any, context: any, info: any) => {
    const result = new PrismaSelect(info).value;
    if (Object.keys(result.select).length > 0) {
        args = {
            ...args,
            ...result,
        };
    }
    return resolve(root, args, context, info);
};

const schema = applyMiddleware(makeExecutableSchema({ typeDefs, resolvers }), middleware);

export default schema;

You can now use the schema with Apollo Server or any other graphql server:

Example

For models User and Post:

query GetUserWithPosts($userId: String!) {
  user(where: { id: { equals: $userId } }) { 
    id
    displayName
    photoURL
    posts {
      id
      text
    }
  }
}

query GetAllUsers { 
  users {
    id
    displayName
    photoURL
  }
}

Generator Configurations

You can customize the generator output with the following configurations:

models Specify models to generate typeDefs and resolvers for.
excludeModels Exclude specific models from generating typeDefs and resolvers.
excludeInputFields Exclude fields from filtering in GraphQL queries.
excludeOutputFields Exclude fields from GraphQL outputs.
output Set a custom output directory for the generator (Defaults to the same directory as schema.prisma file).