Small companion code and doc changes (#3586)

* move migration guide for companion

* improve doc

* add comment about session usage

* remove unused options.multipleInstances

packages/@uppy/companion/src/companion.js

@@ -79,7 +79,7 @@ module.exports.app = (optionsArg = {}) => {
   if (options.redisUrl) {
     redis.client(merge({ url: options.redisUrl }, options.redisOptions || {}))
   }
-  emitter(options.multipleInstances && options.redisUrl, options.redisPubSubScope)
+  emitter(options.redisUrl, options.redisPubSubScope)
 
   const app = express()
 

packages/@uppy/companion/src/standalone/helper.js

@@ -109,7 +109,6 @@ const getConfigFromEnv = () => {
     allowLocalUrls: process.env.COMPANION_ALLOW_LOCAL_URLS === 'true',
     // cookieDomain is kind of a hack to support distributed systems. This should be improved but we never got so far.
     cookieDomain: process.env.COMPANION_COOKIE_DOMAIN,
-    multipleInstances: true,
     streamingUpload: process.env.COMPANION_STREAMING_UPLOAD === 'true',
     maxFileSize: process.env.COMPANION_MAX_FILE_SIZE ? parseInt(process.env.COMPANION_MAX_FILE_SIZE, 10) : undefined,
     chunkSize: process.env.COMPANION_CHUNK_SIZE ? parseInt(process.env.COMPANION_CHUNK_SIZE, 10) : undefined,

packages/@uppy/companion/src/standalone/index.js

@@ -153,6 +153,10 @@ module.exports = function server (inputCompanionOptions = {}) {
     }
   }
 
+  // Session is used for grant redirects, so that we don't need to expose secret tokens in URLs
+  // See https://github.com/transloadit/uppy/pull/1668
+  // https://github.com/transloadit/uppy/issues/3538#issuecomment-1069232909
+  // https://github.com/simov/grant#callback-session
   router.use(session(sessionOptions))
 
   // Routes

website/src/docs/companion.md

@@ -337,7 +337,7 @@ const options = {
 
 * `protocol` - `http | https` - even though companion itself always runs as http, you may want to set this to `https` if you are running a reverse https proxy in front of companion.
 * `host` (required) - your server’s publically facing hostname (for example `example.com`).
-* `oauthDomain` - if you have several instances of Companion with different (and perhaps dynamic) subdomains, you can set a single fixed domain (e.g `sub1.example.com`) to handle your OAuth authentication for you. This would then redirect back to the correct instance with the required credentials on completion. This way you only need to configure a single callback URL for OAuth providers.
+* `oauthDomain` - if you have several instances of Companion with different (and perhaps dynamic) subdomains, you can set a single fixed subdomain and server (e.g `sub1.example.com`) to handle your OAuth authentication for you. This would then redirect back to the correct instance with the required credentials on completion. This way you only need to configure a single callback URL for OAuth providers.
 * `path` - the server path to where the Uppy app is sitting (e.g if Companion is at `example.com/companion`, then the path would be `/companion`).
 * `implicitPath` - if the URL’s path in your reverse proxy is different from your Companion path in your express app, then you need to set this path as `implicitPath`. So if your Companion URL is `example.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`.
 * `validHosts` - if you are setting an `oauthDomain`, you need to set a list of valid hosts, so the oauth handler can validate the host of the Uppy instance requesting the authentication. This is essentially a list of valid domains running your Companion instances. The list may also contain regex patterns. e.g `['sub2.example.com', 'sub3.example.com', '(\\w+).example.com']`
@@ -541,41 +541,6 @@ See also [example code with a custom provider](https://github.com/transloadit/up
 }
 ```
 
-## Migrating v1 to v2
-
-### Prerequisite
-
-Since v2, you now need to be running `node.js >= v10.20.1` to use Companion.
-
-### ProviderOptions
-
-In v2 the `google` and `microsoft` [providerOptions](https://uppy.io/docs/companion/#Options) 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
-
-to:
-
-`http(s)://$COMPANION_HOST_NAME/$PROVIDER_NAME/redirect` in v2
-
-#### New Redirect URIs
-
-<div class="table-responsive">
-
-| Provider | New Redirect URI
-|-|-|
-| Dropbox | `https://$COMPANION_HOST_NAME/dropbox/redirect` |
-| Google Drive | `https://$COMPANION_HOST_NAME/drive/redirect` |
-| OneDrive | `https://$COMPANION_HOST_NAME/onedrive/redirect` |
-| Box | `https://$YOUR_COMPANION_HOST_NAME/box/redirect` |
-| Facebook | `https://$COMPANION_HOST_NAME/facebook/redirect` |
-| Instagram | `https://$COMPANION_HOST_NAME/instagram/redirect` |
-
-</div>
-
 ## Development
 
 1\. To set up Companion for local development, please clone the Uppy repo and install, like so:

website/src/docs/migration-guides.md

@@ -247,6 +247,41 @@ Uppy 1.0 will continue to receive bug fixes for three more months (until <time d
 
 We hope you’ll waste no time in taking Uppy 2.0 out for a walk. When you do, please let us know what you thought of it on [Reddit](https://www.reddit.com/r/javascript/comments/penbr7/uppy_file_uploader_20_smaller_and_faster_modular/), [HN](https://news.ycombinator.com/item?id=28359287), ProductHunt, or [Twitter](https://twitter.com/uppy_io/status/1432399270846603264). We’re howling at the moon to hear from you!
 
+## Migrating Companion v1 to v2
+
+### Prerequisite
+
+Since v2, you now need to be running `node.js >= v10.20.1` to use Companion.
+
+### ProviderOptions
+
+In v2 the `google` and `microsoft` [providerOptions](https://uppy.io/docs/companion/#Options) 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
+
+to:
+
+`http(s)://$COMPANION_HOST_NAME/$PROVIDER_NAME/redirect` in v2
+
+#### New Redirect URIs
+
+<div class="table-responsive">
+
+| Provider | New Redirect URI
+|-|-|
+| Dropbox | `https://$COMPANION_HOST_NAME/dropbox/redirect` |
+| Google Drive | `https://$COMPANION_HOST_NAME/drive/redirect` |
+| OneDrive | `https://$COMPANION_HOST_NAME/onedrive/redirect` |
+| Box | `https://$YOUR_COMPANION_HOST_NAME/box/redirect` |
+| Facebook | `https://$COMPANION_HOST_NAME/facebook/redirect` |
+| Instagram | `https://$COMPANION_HOST_NAME/instagram/redirect` |
+
+</div>
+
 <!-- definitions -->
 
 [core]: /docs/uppy/