Uppy is an open source project by Transloadit
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Drag and drop, webcam, basic file manipulation (adding metadata, for example) and uploading via tus-resumable uploads or XHR/Multipart are all possible using just the Uppy client module.

However, if you add Companion to the mix, your users will be able to select files from remote sources, such as Instagram, Google Drive and Dropbox, bypassing the client (so a 5 GB video isn’t eating into your users’ data plans), and then uploaded to the final destination. Files are removed from Companion after an upload is complete, or after a reasonable timeout. Access tokens also don’t stick around for long, for security reasons.

Companion handles the server-to-server communication between your server and file storage providers such as Google Drive, Dropbox, Instagram, etc. Note that you can not upload files to Companion, it just handles the third party integrations.

Supported providers

As of now, Companion is integrated to work with:

  • Google Drive (name drive) - Set up instructions
  • Dropbox (name dropbox) - Set up instructions
  • Instagram (name instagram)
  • Facebook (name facebook)
  • OneDrive (name onedrive)
  • Remote URLs (name url)
  • Amazon S3 (name s3)


Install from NPM:

npm install @uppy/companion

If you don’t have a Node.js project with a package.json you might want to install/run Companion globally like so: [sudo] npm install -g @uppy/[email protected].


Since v2, you now need to be running node.js >= v10.20.1 to use Companion. Please see Migrating v1 to v2

Unfortunately, Windows is not a supported platform right now. It may work, and we’re happy to accept improvements in this area, but we can’t provide assistance.


Companion may either be used as a pluggable express app, which you plug into your already existing server, or it may simply be run as a standalone server:

Plugging into an already existing server

To plug Companion into an existing server, call its .app method, passing in an options object as a parameter.

var express = require('express')
var bodyParser = require('body-parser')
var session = require('express-session')
var companion = require('@uppy/companion')

var app = express()
app.use(session({secret: 'some secrety secret'}))
// be sure to place this anywhere after app.use(bodyParser.json()) and app.use(session({...})
const options = {
  providerOptions: {
    drive: {
      key: 'GOOGLE_DRIVE_KEY',
      secret: 'GOOGLE_DRIVE_SECRET'
  server: {
    host: 'localhost:3020',
    protocol: 'http',
  filePath: '/path/to/folder/'


please be sure to allow the following HTTP methods in your server like so:

res.header("Access-Control-Allow-Methods", "OPTIONS, GET, POST, PATCH, PUT");

See Options for valid configuration options.

To use WebSockets for realtime upload progress, you can call the socket method, like so:

var server = app.listen(PORT)

companion.socket(server, options)

This takes your server instance and your Uppy Options as parameters.

Running as a standalone server

Please ensure that the required environment variables are set before running/using Companion as a standalone server. See Configure Standalone for the variables required.

Set environment variables first:

export COMPANION_SECRET="shh!Issa Secret!"

And then run:


You can also pass in the path to your JSON config file, like so:

companion --config /path/to/uppyconf.json

Please see Options for possible options.

Configuring a standalone server

To run Companion as a standalone server, you are required to set your Uppy Options via environment variables:

####### Mandatory variables ###########

# any long set of random characters for the server session
export COMPANION_SECRET="shh!Issa Secret!"
# specifying a secret file will override a directly set secret
# corresponds to the server.host option
# corresponds to the filePath option

###### Optional variables ##########

# corresponds to the server.protocol option, defaults to http
# the port on which to start the server, defaults to 3020
# corresponds to the server.port option, defaults to ''
# disables the welcome page, defaults to false
# disables the metrics page, defaults to false

# use this in place of COMPANION_PATH if the server path should not be
# handled by the express.js app, but maybe by an external server configuration
# instead (e.g Nginx).

# comma-separated client hosts to whitlelist by the server
# if not specified, the server would allow any host
export COMPANION_CLIENT_ORIGINS="localhost:3452,uppy.io"

# corresponds to the redisUrl option
# this also enables Redis session storage if set

# to enable Dropbox
# specifying a secret file will override a directly set secret

# to enable Google Drive
# specifying a secret file will override a directly set secret

# to enable Instagram
# specifying a secret file will override a directly set secret

# to enable Facebook
# specifying a secret file will override a directly set secret

# to enable Onedrive
# specifying a secret file will override a directly set secret

# to enable Zoom
# specifying a secret file will override a directly set secret

# to enable S3
# specifying a secret file will override a directly set secret
# to enable S3 Transfer Acceleration (default: false)
# to set X-Amz-Expires query param in presigned urls (in seconds, default: 300)
# to set a canned ACL for uploaded objects: https://docs.aws.amazon.com/AmazonS3/latest/dev/acl-overview.html#canned-acl
export COMPANION_AWS_ACL="public-read"

# corresponds to the server.oauthDomain option
export COMPANION_OAUTH_DOMAIN="sub.domain.com"
# corresponds to the server.validHosts option
export COMPANION_DOMAINS="sub1.domain.com,sub2.domain.com,sub3.domain.com"

# corresponds to the sendSelfEndpoint option

# comma-separated URLs
# corresponds to the uploadUrls option
export COMPANION_UPLOAD_URLS="http://master.tus.io/files/,https://master.tus.io/files/"

See env.example.sh for an example configuration script.


  providerOptions: {
    drive: {
      key: "***",
      secret: "***"
    dropbox: {
      key: "***",
      secret: "***"
    instagram: {
      key: "***",
      secret: "***"
    facebook: {
      key: "***",
      secret: "***"
    onedrive: {
      key: "***",
      secret: "***"
    s3: {
      getKey: (req, filename, metadata) => filename,
      key: "***",
      secret: "***",
      bucket: "bucket-name",
      region: "us-east-1",
      useAccelerateEndpoint: false, // default: false,
      expires: 3600, // default: 300 (5 minutes)
      acl: "private" // default: public-read
  server: {
    host: "localhost:3020", // or yourdomain.com
    protocol: "http"
  filePath: "path/to/download/folder",
  sendSelfEndpoint: "localhost:3020",
  secret: 'mysecret',
  uploadUrls: ['https://myuploadurl.com', 'http://myuploadurl2.com']
  debug: true
  1. filePath(required) - Full path to the directory to which provider files would be downloaded temporarily.

  2. redisUrl(optional) - URL to running Redis server. If this is set, the state of uploads would be stored temporarily. This helps for resumed uploads after a browser crash from the client. The stored upload would be sent back to the client on reconnection.

  3. redisOptions(optional) - An object of options supported by redis client. This option can be used in place of redisUrl.

  4. providerOptions(optional) - An object containing credentials (key and secret) for each provider you would like to enable. Please see the list of supported providers.

  5. server(optional) - An object with details, mainly used to carry out oauth authentication from any of the enabled providers above. Though it is optional, it is required if you would be enabling any of the supported providers. The following are the server options you may set:

    • protocol - http | https
    • host(required) - your server host (e.g localhost:3020, mydomain.com)
    • path - the server path to where the Uppy app is sitting (e.g if Companion is at mydomain.com/companion, then the path would be /companion).
    • oauthDomain - if you have multiple instances of Companion with different (and perhaps dynamic) subdomains, you can set a master domain (e.g sub1.mydomain.com) to handle your oauth authentication for you. This would then redirect to the slave subdomain with the required credentials on completion.
    • validHosts - if you are setting a master oauthDomain, you need to set a list of valid hosts, so the master oauth handler can validate the host of the Uppy instance requesting the authentication. This is basically a list of valid domains running your Companion instances. The list may also contain regex patterns. e.g ['sub2.mydomain.com', 'sub3.mydomain.com', '(\\w+).mydomain.com']
    • implicitPath - if the URL path to your Companion server is set in your NGINX server (or any other Http server) instead of your express app, then you need to set this path as implicitPath. So if your Companion URL is mydomain.com/mypath/companion. Where the path /mypath is defined in your NGINX server, while /companion is set in your express app. Then you need to set the option implicitPath to /mypath, and set the path option to /companion.
  6. sendSelfEndpoint(optional) - This is basically the same as the server.host + server.path attributes. The major reason for this attribute is that, when set, it adds the value as the i-am header of every request response.

  7. customProviders(optional) - This option enables you to add custom providers along with the already supported providers. See Adding Custom Providers for more information.

  8. uploadUrls(optional) - An array of URLs (full paths). If specified, Companion will only accept uploads to these URLs (useful when you want to make sure a Companion instance is only allowed to upload to your servers, for example).

  9. secret(required) - A secret string which Companion uses to generate authorization tokens.

  10. debug(optional) - A boolean flag to tell Companion whether or not to log useful debug information while running.

Provider Redirect URIs

When generating your provider API keys on their corresponding developer platforms (e.g Google Developer Console), you’d need to provide a redirect URI for the OAuth authorization process. In general the redirect URI for each provider takes the format:


For example, if your Companion server is hosted on https://my.companion.server.com, then the redirect URI you would supply for your OneDrive provider would be:


Please see Supported Providers for a list of all Providers and their corresponding names.

S3 options

Companion comes with signature endpoints for AWS S3. These can be used by the Uppy client to sign requests to upload files directly to S3, without exposing secret S3 keys in the browser. Companion also supports uploading files from providers like Dropbox and Instagram directly into S3.

The S3 features can be configured using the providerOptions.s3 property.


The S3 access key ID. The standalone Companion server populates this with the value of the COMPANION_AWS_KEY environment variable by default.


The S3 secret access key. The standalone Companion server populates this with the value of the COMPANION_AWS_SECRET environment variable by default.


The name of the bucket to store uploaded files in. The standalone Companion server populates this with the value of the COMPANION_AWS_BUCKET environment variable by default.


The datacenter region where the target bucket is located. The standalone Companion server populates this with the value of the COMPANION_AWS_REGION environment variable by default.


You can supply any S3 option supported by the AWS SDK in the providerOptions.s3.awsClientOptions object, except for the below:

  • accessKeyId. Instead, use the providerOptions.s3.key property. This is to make configuration names consistent between different Companion features.
  • secretAccessKey. Instead, use the providerOptions.s3.secret property. This is to make configuration names consistent between different Companion features.

Be aware that some options may cause wrong behaviour if they conflict with Companion’s assumptions. If you find that a particular option does not work as expected, please open an issue on the Uppy repository so we can document it here.

providerOptions.s3.getKey(req, filename, metadata)

Get the key name for a file. The key is the file path to which the file will be uploaded in your bucket. This option should be a function receiving three arguments:

  • req, the HTTP request, for regular S3 uploads using the @uppy/aws-s3 plugin. This parameter is not available for multipart uploads using the @uppy/aws-s3-multipart plugin;
  • filename, the original name of the uploaded file;
  • metadata, user-provided metadata for the file. See the @uppy/aws-s3 docs. Currently, the @uppy/aws-s3-multipart plugin unconditionally sends all metadata fields, so all of them are available here.

This function should return a string key. The req parameter can be used to upload to a user-specific folder in your bucket, for example:

  providerOptions: {
    s3: {
      getKey: (req, filename, metadata) => `${req.user.id}/${filename}`,
      /* auth options */

The default implementation returns the filename, so all files will be uploaded to the root of the bucket as their original file name.

  getKey: (req, filename, metadata) => filename

Running in Kubernetes

We have a detailed guide on running Companion in Kubernetes for you, that’s how we currently run our example server at https://companion.uppy.io.

Adding custom providers

As of now, Companion supports the providers listed here out of the box, but you may also choose to add your own custom providers. You can do this by passing the customProviders option when calling the Uppy app method. The custom provider is expected to support Oauth 1 or 2 for authentication/authorization.

let options = {
    customProviders: {
        myprovidername: {
            config: {
                authorize_url: "https://mywebsite.com/authorize",
                access_url: "https://mywebsite.com/token",
                oauth: 2,
                key: "***",
                secret: "***",
                scope: ["read", "write"]
            module: require('/path/to/provider/module')


The customProviders option should be an object containing each custom provider. Each custom provider would, in turn, be an object with two keys, config and module. The config option would contain Oauth API settings, while the module would point to the provider module.

To work well with Companion, the Module must be a class with the following methods.

  1. list (options, done) - lists JSON data of user files (e.g. list of all the files in a particular directory).
    • options - is an object containing the following attributes
      • token - authorization token (retrieved from oauth process) to send along with your request
      • directory - the id/name of the directory from which data is to be retrieved. This may be ignored if it doesn’t apply to your provider
      • query - expressjs query params object received by the server (just in case there is some data you need in there).
    • done (err, data) - the callback that should be called when the request to your provider is made. As the signature indicates, the following data should be passed along to the callback err, and data.
  2. download (options, onData) - downloads a particular file from the provider.
    • options - is an object containing the following attributes:
      • token - authorization token (retrieved from oauth process) to send along with your request.
      • id - ID of the file being downloaded.
      • query - expressjs query params object received by the server (just in case there is some data you need in there).
    • onData (err, chunk) - a callback that should be called with each data chunk received as download is happening. The err argument is an error that should be passed if an error occurs during download. It should be null if there’s no error. Once the download is completed and there are no more chunks to receive, onData should be called with null values like so onData(null, null)
  3. size (options, done) - returns the byte size of the file that needs to be downloaded.
    • options - is an object containing the following attributes:
      • token - authorization token (retrieved from oauth process) to send along with your request.
      • id - ID of the file being downloaded.
    • done (err, size) - the callback that should be called after the request to your provider is completed. As the signature indicates, the following data should be passed along to the callback err, and size (number).

The class must also have an authProvider string (lowercased) field which typically indicates the name of the provider (e.g “dropbox”).

list data

  // username or email of the user whose provider account is being accessed
  username: 'johndoe',
  // list of files and folders in the directory. An item is considered a folder
  //  if it mainly exists as a collection to contain sub-items
  items: [
      // boolean value of whether or NOT it's a folder
      isFolder: false,
      // icon image URL
      icon: 'https://random-api.url.com/fileicon.jpg',
      // name of the item
      name: 'myfile.jpg',
      // the mime type of the item. Only relevant if the item is NOT a folder
      mimeType: 'image/jpg',
      // the id (in string) of the item
      id: 'uniqueitemid',
      // thumbnail image URL. Only relevant if the item is NOT a folder
      thumbnail: 'https://random-api.url.com/filethumbnail.jpg',
      // for folders this is typically the value that will be passed as "directory" in the list(...) method.
      // For files, this is the value that will be passed as id in the download(...) method.
      requestPath: 'file-or-folder-requestpath',
      // datetime string (in ISO 8601 format) of when this item was last modified
      modifiedDate: '2020-06-29T19:59:58Z',
      // the size in bytes of the item. Only relevent if the item is NOT a folder
      size: 278940,
      custom: {
        // an object that may contain some more custom fields that you may need to send to the client. Only add this object if you have a need for it.
        customData1: 'the value',
        customData2: 'the value',
      // more items here
  // if the "items" list is paginated, this is the request path needed to fetch the next page.
  nextPagePath: 'directory-name?cursor=cursor-to-next-page'

Migrating v1 to v2


Since v2, you now need to be running node.js >= v10.20.1 to use Companion.


In v2 the google and microsoft providerOptions have been changed to drive and onedrive respectively.

OAuth Redirect URIs

On your Providers’ respective developer platforms, the OAuth redirect URIs that you should supply has now changed from:

http(s)://$COMPANION_HOST_NAME/connect/$AUTH_PROVIDER/callback in v1


http(s)://$COMPANION_HOST_NAME/$PROVIDER_NAME/redirect in v2

New Redirect URIs

Provider New Redirect URI
Dropbox https://$COMPANION_HOST_NAME/dropbox/redirect
Google Drive https://$COMPANION_HOST_NAME/drive/redirect
OneDrive https://$COMPANION_HOST_NAME/onedrive/redirect
Facebook https://$COMPANION_HOST_NAME/facebook/redirect
Instagram https://$COMPANION_HOST_NAME/instagram/redirect


1. To set up Companion for local development, please clone the Uppy repo and install, like so:

git clone https://github.com/transloadit/uppy && cd uppy && npm install

2. Configure your environment variables by copying the env.example.sh file to env.sh and edit it to its correct values.

cp env.example.sh env.sh
$EDITOR env.sh

3. To start the server, run:

npm run start:companion

This would get the Companion instance running on http://localhost:3020. It uses nodemon so it will automatically restart when files are changed.

Live example

An example server is running at https://companion.uppy.io, which is deployed with Kubernetes

How the Authentication and Token mechanism works

This section describes how Authentication works between Companion and Providers. While this behaviour is the same for all Providers (Dropbox, Instagram, Google Drive), we are going to be referring to Dropbox in place of any Provider throughout this section.

The following steps describe the actions that take place when a user Authenticates and Uploads from Dropbox through Companion:

  • The visitor to a website with Uppy clicks “Connect to Dropbox”.
  • Uppy sends a request to Companion, which in turn sends an OAuth request to Dropbox (Requires that OAuth credentials from Dropbox have been added to Companion).
  • Dropbox asks the visitor to log in, and whether the Website should be allowed to access your files
  • If the visitor agrees, Companion will receive a token from Dropbox, with which we can temporarily download files.
  • Companion encrypts the token with a secret key and sends the encrypted token to Uppy (client)
  • Every time the visitor clicks on a folder in Uppy, it asks Companion for the new list of files, with this question, the token (still encrypted by Companion) is sent along.
  • Companion decrypts the token, requests the list of files from Dropbox and sends it to Uppy.
  • When a file is selected for upload, Companion receives the token again according to this procedure, decrypts it again, and thereby downloads the file from Dropbox.
  • As the bytes arrive, Companion uploads the bytes to the final destination (depending on the configuration: Apache, a Tus server, S3 bucket, etc).
  • Companion reports progress to Uppy, as if it were a local upload.
  • Completed!