Apollo Federation file upload

This library makes it easier to support file uploads to your federated
micro-services. It uses the Apollo server's solution.
It works by simply redirecting the file uploaded stream to the micro-service.
This package does not use third-party services to send the package to your
micro-services.

Apollo Federation V2 Support

Please, use version 4.0.0+. For Federation V1 use 3.0.0 or earlier.

Using HTTP Transfer-Encoding: chunked

By default, the FileUploadDataSource uses chunked transfers; we
advise that you do not change this setup. However, for some reason
you can't support this kind of transfer, one can provide the useChunkedTransfer
option to the FileUploadDataSource constructor as false to not
use chunked transfer (See the example below on setting this property).
Be advised once again that this can lead to DDOS attacks.

Preventing CSRF attacks

This package uses graphql-upload, if you want to prevent a CSRF attack you should keep
the CSRF prevention feature enabled, and configure your upload clients to send a non-empty
Apollo-Require-Preflight header.

You can take a look at Apollo's security guide for more details.

#### How to enable CRSF Prevention

``javascript
import { ApolloServer } from 'apollo-server';

const runServer = async () => {
const server = new ApolloServer({
/*
If activated it will request by default a header with ['x-apollo-operation-name', 'apollo-require-preflight']

You can also change the allowed headers by passing them to csrfPrevention.requestHeaders
*/
csrfPrevention: true,
...
});
...
};

...
`

Example

On your Gateway, you must add the FileUploadDataSource in order
to the micro-service be able to receive the uploaded file(s).


`javascript
import { ApolloServer } from 'apollo-server';
import { ApolloGateway } from '@apollo/gateway';
import FileUploadDataSource from '@profusion/apollo-federation-upload';

const runServer = async () => {
const server = new ApolloServer({
gateway: new ApolloGateway({
// Add this line in order to support file uploads.
buildService: ({ url }) => new FileUploadDataSource({ url, useChunkedTransfer: true }),
serviceList: [
/ The services ... /
],
})
});

const { url } = await server.listen();

console.log(🚀 Server ready at ${url});
};

runServer().catch(error => {
console.error('💥 Failed to start server:', error);
process.exit(1);
});
``