apollo-upload-client

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).

Installation

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.

Usage

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.

FileList

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} />;
}

File

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} />;
}

Blob

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} />;
}

Requirements

• 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

API

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

class ReactNativeFile

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.

| Parameter | Type | Description | | :-- | :-- | :-- | | file | ReactNativeFileSubstitute | A React Native File substitute. |

See

• extract-files ReactNativeFile docs.

Examples

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",
});

function createUploadLink

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.

| Parameter | Type | Description | | :-- | :-- | :-- | | options | object | Options. | | options.uri | string? = /graphql | GraphQL endpoint URI. | | options.useGETForQueries | boolean? | Should GET be used to fetch queries, if there are no files to upload. | | options.isExtractableFile | ExtractableFileMatcher? = isExtractableFile | Customizes how files are matched in the GraphQL operation for extraction. | | options.FormData | class? | FormData implementation to use, defaulting to the FormData global. | | options.formDataAppendFile | FormDataFileAppender? = formDataAppendFile | Customizes how extracted files are appended to the FormData instance. | | options.fetch | Function? | fetch implementation to use, defaulting to the fetch global. | | options.fetchOptions | FetchOptions? | fetch options; overridden by upload requirements. | | options.credentials | string? | Overrides options.fetchOptions.credentials. | | options.headers | object? | Merges with and overrides options.fetchOptions.headers. | | options.includeExtensions | boolean? = false | Toggles sending extensions fields to the GraphQL server. |

Returns: ApolloLink — A terminating Apollo Link.

See

• GraphQL multipart request spec.

Examples

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 "@harshitp96/client";
import createUploadLink from "apollo-upload-client/public/createUploadLink.js";

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

function formDataAppendFile

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

Type: FormDataFileAppender

| Parameter | Type | Description | | :-- | :-- | :-- | | formData | FormData | FormData instance to append the specified file to. | | fieldName | string | Field name for the file. | | file | * | File to append. |

Examples

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");

function isExtractableFile

The default implementation for createUploadLink options.isExtractableFile.

Type: ExtractableFileMatcher

| Parameter | Type | Description | | :-------- | :--- | :-------------- | | value | * | Value to check. |

Returns: boolean — Is the value an extractable file.

See

• extract-files isExtractableFile docs.

Examples

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");

type ExtractableFileMatcher

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

Type: Function

| Parameter | Type | Description | | :-------- | :--- | :-------------- | | value | * | Value to check. |

Returns: boolean — Is the value an extractable file.

See

• isExtractableFile has this type.

Examples

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);

type FetchOptions

GraphQL request fetch options.

Type: object

| Property | Type | Description | | :------------ | :------ | :------------------------------- | | headers | object | HTTP request headers. | | credentials | string? | Authentication credentials mode. |

See

• Polyfillable fetch options.

type FormDataFileAppender

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

| Parameter | Type | Description | | :-- | :-- | :-- | | formData | FormData | FormData instance to append the specified file to. | | fieldName | string | Field name for the file. | | file | * | File to append. The file type depends on what the ExtractableFileMatcher extracts. |

See

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

type ReactNativeFileSubstitute

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

| Property | Type | Description | | :-- | :-- | :-- | | uri | string | Filesystem path. | | name | string? | File name. | | type | string? | File content type. Some environments (particularly Android) require a valid MIME type; Expo ImageResult.type is unreliable as it can be just image. |

See

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

Examples

A camera roll file.

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