A terminating Apollo Link for Apollo Client that fetches a GraphQL multipart request if the GraphQL variables contain files (by default FileList, File, Blob, or ReactNativeFile instances), or else fetches a regular GraphQL POST or GET request (depending on the config and GraphQL operation).

To install with npm, run:

npm install apollo-upload-client

Remove any uri, credentials, or headers options from the ApolloClient constructor.

Apollo Client can only have 1 terminating Apollo Link that sends the GraphQL requests; if one such as HttpLink is already setup, remove it.

Initialize the client with a terminating Apollo Link using createUploadLink.

Also ensure the GraphQL server implements the GraphQL multipart request spec and that uploads are handled correctly in resolvers.

Use FileList, File, Blob or ReactNativeFile instances anywhere within query or mutation variables to send a GraphQL multipart request.

See also the example API and client.

import { gql, useMutation } from "@apollo/client";

const MUTATION = gql`
  mutation ($files: [Upload!]!) {
    uploadFiles(files: $files) {
      success
    }
  }
`;

function UploadFiles() {
  const [mutate] = useMutation(MUTATION);

  function onChange({ target: { validity, files } }) {
    if (validity.valid) mutate({ variables: { files } });
  }

  return <input type="file" multiple required onChange={onChange} />;
}

import { gql, useMutation } from "@apollo/client";

const MUTATION = gql`
  mutation ($file: Upload!) {
    uploadFile(file: $file) {
      success
    }
  }
`;

function UploadFile() {
  const [mutate] = useMutation(MUTATION);

  function onChange({
    target: {
      validity,
      files: [file],
    },
  }) {
    if (validity.valid) mutate({ variables: { file } });
  }

  return <input type="file" required onChange={onChange} />;
}

import { gql, useMutation } from "@apollo/client";

const MUTATION = gql`
  mutation ($file: Upload!) {
    uploadFile(file: $file) {
      success
    }
  }
`;

function UploadFile() {
  const [mutate] = useMutation(MUTATION);

  function onChange({ target: { validity, value } }) {
    if (validity.valid) {
      const file = new Blob([value], { type: "text/plain" });

      // Optional, defaults to `blob`.
      file.name = "text.txt";

      mutate({ variables: { file } });
    }
  }

  return <input type="text" required onChange={onChange} />;
}

• Node.js: ^14.17.0 || ^16.0.0 || >= 18.0.0
• Browsers: > 0.5%, not OperaMini all, not IE > 0, not dead
• React Native

Consider polyfilling:

• Promise
• fetch
• FormData

• class ReactNativeFile
• function createUploadLink
• function formDataAppendFile
• function isExtractableFile
• type ExtractableFileMatcher
• type FetchOptions
• type FormDataFileAppender
• type ReactNativeFileSubstitute

Used to mark React Native File substitutes as it’s too risky to assume all objects with uri, type and name properties are extractable files.

• extract-files ReactNativeFile docs.

Ways to import.

import { ReactNativeFile } from "apollo-upload-client";

import ReactNativeFile from "apollo-upload-client/public/ReactNativeFile.js";

Ways to require.

const { ReactNativeFile } = require("apollo-upload-client");

const ReactNativeFile = require("apollo-upload-client/public/ReactNativeFile.js");

A file in React Native that can be used in query or mutation variables.

const file = new ReactNativeFile({
  uri: uriFromCameraRoll,
  name: "a.jpg",
  type: "image/jpeg",
});

Creates a terminating Apollo Link for Apollo Client that fetches a GraphQL multipart request if the GraphQL variables contain files (by default FileList, File, Blob, or ReactNativeFile instances), or else fetches a regular GraphQL POST or GET request (depending on the config and GraphQL operation).

Some of the options are similar to the createHttpLink options.

Returns: ApolloLink — A terminating Apollo Link.

• GraphQL multipart request spec.

Ways to import.

import { createUploadLink } from "apollo-upload-client";

import createUploadLink from "apollo-upload-client/public/createUploadLink.js";

Ways to require.

const { createUploadLink } = require("apollo-upload-client");

const createUploadLink = require("apollo-upload-client/public/createUploadLink.js");

A basic Apollo Client setup.

import { ApolloClient, InMemoryCache } from "@apollo/client";
import createUploadLink from "apollo-upload-client/public/createUploadLink.js";

const client = new ApolloClient({
  cache: new InMemoryCache(),
  link: createUploadLink(),
});

The default implementation for createUploadLink options.formDataAppendFile that uses the standard FormData.append method.

Type: FormDataFileAppender

Ways to import.

import { formDataAppendFile } from "apollo-upload-client";

import formDataAppendFile from "apollo-upload-client/public/formDataAppendFile.js";

Ways to require.

const { formDataAppendFile } = require("apollo-upload-client");

const formDataAppendFile = require("apollo-upload-client/public/formDataAppendFile.js");

The default implementation for createUploadLink options.isExtractableFile.

Type: ExtractableFileMatcher

Returns: boolean — Is the value an extractable file.

• extract-files isExtractableFile docs.

Ways to import.

import { isExtractableFile } from "apollo-upload-client";

import isExtractableFile from "apollo-upload-client/public/isExtractableFile.js";

Ways to require.

const { isExtractableFile } = require("apollo-upload-client");

const isExtractableFile = require("apollo-upload-client/public/isExtractableFile.js");

A function that checks if a value is an extractable file.

Type: Function

Returns: boolean — Is the value an extractable file.

• isExtractableFile has this type.

How to check for the default exactable files, as well as a custom type of file.

import isExtractableFile from "apollo-upload-client/public/isExtractableFile.js";

const isExtractableFileEnhanced = (value) =>
  isExtractableFile(value) ||
  (typeof CustomFile !== "undefined" && value instanceof CustomFile);

GraphQL request fetch options.

Type: object

• Polyfillable fetch options.

Appends a file extracted from the GraphQL operation to the FormData instance used as the fetch options.body for the GraphQL multipart request.

• formDataAppendFile has this type.
• createUploadLink accepts this type in options.formDataAppendFile.

A React Native File substitute.

Be aware that inspecting network traffic with buggy versions of dev tools such as Flipper can interfere with the React Native FormData implementation, causing multipart requests to have network errors.

Type: object

• extract-files ReactNativeFileSubstitute docs.
• React Native FormData polyfill source.

A camera roll file.

const fileSubstitute = {
  uri: uriFromCameraRoll,
  name: "a.jpg",
  type: "image/jpeg",
};