---
name: graphql-implementation-a05e9c64f3aa
description: Builds GraphQL APIs with schema design, resolvers, error handling, and performance optimization using Apollo or Graphene. Use when creating flexible query APIs, migrating from REST, or implementing real-time subscriptions.
license: MIT
---

# GraphQL Implementation

Build GraphQL APIs with proper schema design, resolvers, and performance optimization.

## Schema Definition

```graphql
type User {
  id: ID!
  name: String!
  email: String!
  posts(limit: Int = 10): [Post!]!
}

type Post {
  id: ID!
  title: String!
  content: String!
  author: User!
  createdAt: DateTime!
}

type Query {
  user(id: ID!): User
  users(limit: Int, offset: Int): [User!]!
  post(id: ID!): Post
}

type Mutation {
  createUser(input: CreateUserInput!): User!
  createPost(input: CreatePostInput!): Post!
}

input CreateUserInput {
  name: String!
  email: String!
}
```

## Apollo Server Setup

```javascript
const { ApolloServer } = require('@apollo/server');
const { startStandaloneServer } = require('@apollo/server/standalone');

const resolvers = {
  Query: {
    user: (_, { id }, { dataSources }) =>
      dataSources.userAPI.getUser(id),
    users: (_, { limit, offset }, { dataSources }) =>
      dataSources.userAPI.getUsers({ limit, offset })
  },
  User: {
    posts: (user, { limit }, { dataSources }) =>
      dataSources.postAPI.getPostsByUser(user.id, limit)
  },
  Mutation: {
    createUser: (_, { input }, { dataSources }) =>
      dataSources.userAPI.createUser(input)
  }
};

const server = new ApolloServer({ typeDefs, resolvers });
```

## DataLoader for N+1 Prevention

```javascript
const DataLoader = require('dataloader');

const userLoader = new DataLoader(async (ids) => {
  const users = await User.find({ _id: { $in: ids } });
  return ids.map(id => users.find(u => u.id === id));
});
```

## Error Handling

```javascript
const { GraphQLError } = require('graphql');

throw new GraphQLError('User not found', {
  extensions: { code: 'NOT_FOUND', argumentName: 'id' }
});
```

## Best Practices

- Use DataLoader to batch queries
- Implement query complexity limits
- Design schema around client needs
- Validate all inputs
- Use descriptive naming conventions

## Python Graphene

See [references/python-graphene.md](references/python-graphene.md) for complete Flask implementation with:
- ObjectType definitions
- Query and Mutation classes
- Input types
- Flask integration

## Best Practices

**Do:**
- Use DataLoader to batch queries
- Implement query complexity limits
- Design schema around client needs
- Validate all inputs
- Use descriptive naming conventions
- Add subscriptions for real-time data

**Don't:**
- Allow deeply nested queries without limits
- Expose database internals
- Ignore N+1 query problems
- Return unauthorized data
- Skip input validation


---
Source attribution: secondsky
Original project: https://github.com/secondsky/claude-skills/blob/88378361314f558fb719aec0af9fd898ab36f0b2/plugins/graphql-implementation/skills/graphql-implementation/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2025 Claude Skills Maintainers

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: secondsky
Original project: https://github.com/secondsky/claude-skills/blob/88378361314f558fb719aec0af9fd898ab36f0b2/plugins/graphql-implementation/skills/graphql-implementation/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Product Management
Roles: Backend Developer, Full-Stack Developer, Data Engineer, Product Manager, Technical Product Manager
Specialties: Frontend, Design, API, Database, Backend
Tools: Apollo, Graphene
Country applicability: Country not specified
Classification basis: Source category, role and specialization labels
Instruction SHA-256: f1b09a2b59ed0d1bc0516f786d293a71e0effce265133466ddecad56e4661fd5