Using upload as argument (graphql type) for mutation

I have already successfully implemented uploading files successfully in nexus framework - but with schema I ran out of ideas.

According to the docs (https://nexusjs.org/docs/api/scalar-type) this was my approach:

import { arg, extendType }  from '@nexus/schema'

import { GraphQLUpload } from 'apollo-server-express'

export const Upload = GraphQLUpload

extendType({
  type: 'Mutation',
  definition(t) {
    t.crud.deleteOneDocument(),      
    t.field('uploadSingleDocument', {
      type: 'Document',
      args: {
        file: arg({ type: "Upload", required: true })  //here gives me "Type '"Upload"' is not assignable to type 'NexusArgConfigType"
      },
      async resolve (_root, args, ctx) {
           // ....
      },
    })
  },
})

I`ve also tried some of the solutions from issue #441 but seems like they are not working for my environment.

This is my package.json:

{ "name": "test", "version": "1.0.0", "description": "", "main": "index.js", "scripts": { "dev": "ts-node-dev --transpile-only --no-notify api/app.ts", "build": "tsc" }, "keywords": [], "author": "", "license": "ISC", "dependencies": { "@nexus/schema": "^0.16.0", "@prisma/client": "^2.9.0", "apollo-server": "^2.18.2", "apollo-server-express": "^2.18.2", "express": "^4.17.1", "graphql": "^15.3.0", "graphql-scalars": "^1.4.0", "nexus-plugin-prisma": "^0.21.0" }, "devDependencies": { "@prisma/cli": "^2.9.0", "ts-node-dev": "^1.0.0-pre.65", "typescript": "^4.0.3" } }

I am running npm run dev while in the code window. Server is running on apollo-express.

This was my working solution with nexus framework (mutation had same code) for binary/multipart upload:

import { GraphQLUpload } from 'apollo-server-core';
import type { FileUpload } from 'graphql-upload';

export type UploadRoot = Promise<FileUpload>;

schema.scalarType({
  // Why we need the bang: https://github.com/apollographql/apollo-server/blob/570f548b88750a06fbf5f67a4abe78fb0f870ccd/packages/apollo-server-core/src/index.ts#L49-L56
  ...GraphQLUpload!,
  rootTyping: 'UploadRoot',
})

Please help!

[hajnalben]

Thanks for the awesome help @bkiac!

However we will need to register the Upload scalar alongside the resolvers to the makeSchema -> type field.

export const schema = makeSchema({
  types: [...resolvers, Upload], // from: scalars.ts
  // ...
 }

In case anyone wants to centralize your Upload handling you could use the scalarType insteadof asNexusMethod:

// scalars.ts
import { GraphQLUpload } from "apollo-server-express"
import { scalarType } from "nexus"
import { FileUpload } from "graphql-upload"
import { createWriteStream } from "fs"
import { promisify } from "util"
import stream from "stream"
import { join } from "path"

type UploadResult = String

export type Upload = Promise<UploadResult>

export const Upload = scalarType({
  name: 'Upload',
  asNexusMethod: 'upload',
  description: GraphQLUpload.description,
  serialize: GraphQLUpload.serialize,
  parseValue: uploadProcessor,
  parseLiteral: GraphQLUpload.parseLiteral
})

const pipeline = promisify(stream.pipeline);

async function uploadProcessor(value: Promise<any>): Promise<UploadResult> {
  // We want to support URLs as well
  if (typeof value === 'string') {
    return value
  }

  const file: FileUpload = await GraphQLUpload.parseValue(value)

  const path = __dirname + '/' + file.filename

  await pipeline(
    file.createReadStream(),
    createWriteStream(join(__dirname, file.filename))
  )

  return path
}

[bkiac]

This works for me with nexus@^1.0.0, apollo-server-express@^2.19.0

// scalars.ts
import { GraphQLUpload } from "apollo-server-express"
import { FileUpload } from "graphql-upload"
import { asNexusMethod } from "nexus"

export type Upload = Promise<FileUpload>
// Bang is required due to https://github.com/apollographql/apollo-server/blob/570f548b88750a06fbf5f67a4abe78fb0f870ccd/packages/apollo-server-core/src/index.ts#L49-L56
export const Upload = asNexusMethod(GraphQLUpload!, "upload")

// schema.ts
import { makeSchema } from "nexus"
import * as path from "path"

export const schema = makeSchema({
	// ...
	sourceTypes: {
		modules: [
			{
				module: path.join(__dirname, "path/to/scalars.ts"),
				alias: "BackingScalars",
			},
		],
	},
})

// upload.ts
import { arg, mutationField, nonNull } from "nexus"

export const upload = mutationField("upload", {
	type: "String",
	args: {
		data: nonNull(arg({ type: "Upload" })),
	},
	resolve: async (_, args) => {
		const { createReadStream } = await args.data
		const stream = createReadStream()
		// ...
		return "success"
	},
})