# GraphQL Apollo

Plugin for Elysia to use GraphQL Apollo.

## Installation
```bash
bun add graphql @elysiajs/apollo @apollo/server
```

## Basic Usage

```typescript
import { Elysia } from 'elysia'
import { apollo, gql } from '@elysiajs/apollo'

const app = new Elysia()
	.use(
		apollo({
			typeDefs: gql`
				type Book {
					title: String
					author: String
				}

				type Query {
					books: [Book]
				}
			`,
			resolvers: {
				Query: {
					books: () => {
						return [
							{
								title: 'Elysia',
								author: 'saltyAom'
							}
						]
					}
				}
			}
		})
	)
	.listen(3000)
```

Accessing `/graphql` should show Apollo GraphQL playground work with.

## Context

Because Elysia is based on Web Standard Request and Response which is different from Node's `HttpRequest` and `HttpResponse` that Express uses, results in `req, res` being undefined in context.

Because of this, Elysia replaces both with `context` like route parameters.

```typescript
const app = new Elysia()
	.use(
		apollo({
			typeDefs,
			resolvers,
			context: async ({ request }) => {
				const authorization = request.headers.get('Authorization')

				return {
					authorization
				}
			}
		})
	)
	.listen(3000)
```

## Config

This plugin extends Apollo's [ServerRegistration](https://www.apollographql.com/docs/apollo-server/api/apollo-server/#options) (which is `ApolloServer`'s' constructor parameter).

Below are the extended parameters for configuring Apollo Server with Elysia.

### path

@default `"/graphql"`

Path to expose Apollo Server.

---

### enablePlayground

@default `process.env.ENV !== 'production'`

Determine whether should Apollo should provide Apollo Playground.