@boltline/apollo-upload-server

apollo-upload-server

Enhances Apollo for intuitive file uploads via GraphQL queries or mutations. Use with a GraphQL multipart request spec client implementation such as apollo-upload-client.

Setup

To install apollo-upload-server and graphql from npm run:

npm install apollo-upload-server graphql

Add the middleware just before graphql-server.

Options

• maxFieldSize (integer): Max allowed non-file multipart form field size in bytes; enough for your queries (default: 1 MB).
• maxFileSize (integer): Max allowed file size in bytes (default: Infinity).
• maxFiles (integer): Max allowed number of files (default: Infinity).
• errorHandler (function): This function is attached to the error event of each file stream. (default: () => {})).

Koa

import { apolloUploadKoa } from 'apollo-upload-server'

// …

router.post(
  '/graphql',
  koaBody(),
  apolloUploadKoa(/* Options */),
  graphqlKoa(/* … */)
)

Express

import { apolloUploadExpress } from 'apollo-upload-server'

// …

app.use(
  '/graphql',
  bodyParser.json(),
  apolloUploadExpress(/* Options */),
  graphqlExpress(/* … */)
)

Custom middleware

Middleware wraps the async function processRequest which accepts a Node.js request and an optional options object as arguments. It returns a promise that resolves an object of the shape:

type Response = {
  // operations for a GraphQL server to consume (usually as the request body)
  body: *,

  // promise which will resolve once the request has been fully consumed
  finished: Promise<typeof undefined>
}

. Import it to create custom middleware:

import { processRequest } from 'apollo-upload-server'

Upload scalar

A file upload promise that resolves an object containing:

• stream
• filename
• mimetype
• encoding

It must be added to your types and resolvers:

import { makeExecutableSchema } from 'graphql-tools'
import { GraphQLUpload } from 'apollo-upload-server'

const schema = makeExecutableSchema({
  typeDefs: `scalar Upload`,
  resolvers: { Upload: GraphQLUpload }
})

Usage

Files uploaded via a GraphQL multipart request appear as Upload scalars in resolver arguments. The upload streams can be used to store the files in the local filesystem or in the cloud. See also apollo-upload-client usage and the example API and client.

Support

• Node.js v8.5+.