Some docs polish

@arturi

website/src/docs/server.md

@@ -5,23 +5,23 @@ permalink: docs/server/
 order: 2
 ---
 
-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.
+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 [Uppy Server](https://github.com/transloadit/uppy-server) 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 Uppy Server after an upload is complete, or after a reasonable timeout. Access tokens also don’t stick around for long, for security.
+However, if you add [Uppy Server](https://github.com/transloadit/uppy-server) 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 Uppy Server after an upload is complete, or after a reasonable timeout. Access tokens also don’t stick around for long, for security reasons.
 
 Uppy Server handles the server-to-server communication between your server and file storage providers such as Google Drive, Dropbox, Instagram, etc.
 
-## Supported Providers
+## Supported providers
 
-As of now Uppy Server is integrated to work with:
+As of now, Uppy Server is integrated to work with:
 
 - Google Drive
 - Dropbox
 - Instagram
-- Remote Urls
+- Remote URLs
 - Amazon S3
 
-## Install
+## Installation
 
 ```bash
 npm install uppy-server
@@ -29,11 +29,11 @@ npm install uppy-server
 
 ## Usage
 
-Uppy Server may either be used as a pluggable express app, which you plug to your already existing server, or it may simply be run as a standalone server:
+Uppy Server 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:
 
-### Plug to already existing server
+### Plugging into an already existing server
 
-To plug Uppy Server to an existing server, simply call on its `.app` method, passing in an [options](#Options) object as parameter.
+To plug Uppy Server into an existing server, simply call on its `.app` method, passing in an [options](#Options) object as a parameter.
 
 ```javascript
 
@@ -66,7 +66,7 @@ app.use(uppy.app(options))
 ```
 See [Options](#Options) for valid configuration options.
 
-To enable Uppy Socket for realtime upload progress, you can call the `socket` method like so:
+To enable Uppy Socket for realtime upload progress, you can call the `socket` method, like so:
 
 ```javascript
 ...
@@ -75,9 +75,9 @@ var server = app.listen(PORT)
 uppy.socket(server, options)
 
 ```
-This takes your `server` instance and your Uppy [options](#Options) as parameters.
+This takes your `server` instance and your Uppy [Options](#Options) as parameters.
 
-### Run as standalone server
+### Running as a standalone server
 
 > Please ensure that the required environment variables are set before running/using Uppy Server as a standalone server. See [Configure Standalone](#Configure-Standalone) for the variables required.
 
@@ -101,7 +101,7 @@ If you cloned the repo from GitHub and want to run it as a standalone server, yo
 npm start
 ```
 
-You can also pass in the path to your json config file like so:
+You can also pass in the path to your JSON config file, like so:
 
 ```bash
 uppy-server --config /path/to/uppyconf.json
@@ -113,11 +113,11 @@ or
 npm start -- --config /path/to/uppyconf.json
 ```
 
-Please see [options](#Options) for possible options.
+Please see [Options](#Options) for possible options.
 
-#### Configure Standalone
+#### Configuring a standalone server
 
-To run Uppy Server as a standalone server, you are required to set your Uppy [options](#Options) via environment variables:
+To run Uppy Server as a standalone server, you are required to set your Uppy [Options](#Options) via environment variables:
 
 ```bash
 ####### Mandatory variables ###########
@@ -131,24 +131,24 @@ export UPPYSERVER_DATADIR="PATH/TO/DOWNLOAD/DIRECTORY"
 
 ###### Optional variables ##########
 
-# corresponds to the server.protocol option. defaults to http
+# corresponds to the server.protocol option, defaults to http
 export UPPYSERVER_PROTOCOL="YOUR SERVER PROTOCOL"
-# the port to start the server on. defaults to 3020
+# the port on which to start the server, defaults to 3020
 export UPPYSERVER_PORT="YOUR SERVER PORT"
-# corresponds to the server.port option. defaults to ''
+# corresponds to the server.port option, defaults to ''
 export UPPYSERVER_PATH="/SERVER/PATH/TO/WHERE/UPPY-SERVER/LIVES"
 
 # use this in place of UPPYSERVER_PATH if the server path should not be
-# handled by the express.js app but maybe by an external server configuration
+# handled by the express.js app, but maybe by an external server configuration
 # instead (e.g Nginx).
 export UPPYSERVER_IMPLICIT_PATH="/SERVER/PATH/TO/WHERE/UPPY/SERVER/LIVES"
 
-# comma separated client hosts to whitlelist by the server
+# comma-separated client hosts to whitlelist by the server
 # if not specified, the server would allow any host
 export UPPY_ENDPOINTS="localhost:3452,uppy.io"
 
 # corresponds to the redisUrl option
-# This also enables redis session storage if set
+# this also enables Redis session storage if set
 export UPPYSERVER_REDIS_URL="REDIS URL"
 
 # to enable Dropbox
@@ -163,7 +163,7 @@ export UPPYSERVER_GOOGLE_SECRET="YOUR GOOGLE SECRET"
 export UPPYSERVER_INSTAGRAM_KEY="YOUR INSTAGRAM KEY"
 export UPPYSERVER_INSTAGRAM_SECRET="YOUR INSTAGRAM SECRET"
 
-# to enable s3
+# to enable S3
 export UPPYSERVER_AWS_KEY="YOUR AWS KEY"
 export UPPYSERVER_AWS_SECRET="YOUR AWS SECRET"
 export UPPYSERVER_AWS_BUCKET="YOUR AWS S3 BUCKET"
@@ -177,7 +177,7 @@ export UPPYSERVER_DOMAINS="sub1.domain.com,sub2.domain.com,sub3.domain.com"
 # corresponds to the sendSelfEndpoint option
 export UPPYSERVER_SELF_ENDPOINT="THIS SHOULD BE SAME AS YOUR DOMAIN + PATH"
 
-# comma separated urls
+# comma-separated URLs
 # corresponds to the uploadUrls option
 export UPPYSERVER_UPLOAD_URLS="http://master.tus.io/files/,https://master.tus.io/files/"
 ```
@@ -221,37 +221,37 @@ See [env.example.sh](https://github.com/transloadit/uppy-server/blob/master/env.
 }
 ```
 
-1. **filePath(required)** - Full path to the directory where provider files would temporarily be downloaded to.
+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.
+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. **providerOptions(optional)** - An object containing credentials (`key` and `secret`) for each provider you would like to enable. Please see [here for the list of supported providers](#Supported-Providers).
+3. **providerOptions(optional)** - An object containing credentials (`key` and `secret`) for each provider you would like to enable. Please see [the list of supported providers](#Supported-Providers).
 
-4. **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:
+4. **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 uppy server is at `mydomain.com/uppy`, then the path would be `/uppy`).
-  - oauthDomain - if you have multiple instances of uppy server with different (and maybe 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 uppy server instances. The list may also contain regex patterns. e.g `['sub2.mydomain.com', 'sub3.mydomain.com', '(\\w+).mydomain.com']`
+  - path - the server path to where the Uppy app is sitting (e.g if Uppy Server is at `mydomain.com/uppy`, then the path would be `/uppy`).
+  - oauthDomain - if you have multiple instances of Uppy Server 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 Uppy Server instances. The list may also contain regex patterns. e.g `['sub2.mydomain.com', 'sub3.mydomain.com', '(\\w+).mydomain.com']`
 
 5. **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.
 
 6. **customProviders(optional)** - This option enables you to add custom providers along with the already supported providers. See [Adding Custom Providers](#Adding-Custom-Providers) for more information.
 
-7. **uploadUrls(optional)** - An array of urls (full paths). If specified, Uppy Server will only accept uploads to these urls (useful when you want to make sure an Uppy Server instance is only allowed to upload to your servers, for example).
+7. **uploadUrls(optional)** - An array of URLs (full paths). If specified, Uppy Server will only accept uploads to these URLs (useful when you want to make sure an Uppy Server instance is only allowed to upload to your servers, for example).
 
 8. **secret(required)** - A secret string which Uppy Server uses to generate authorization tokens.
 
 9. **debug(optional)** - A boolean flag to tell Uppy Server whether or not to log useful debug information while running.
 
-### S3 Options
+### S3 options
 
 The S3 uploader has some options in addition to the ones necessary for authentication.
 
 #### `s3.getKey(req, filename)`
 
-Get the key name for a file. The key is the file path that the file will be uploaded to in your bucket. This option should be a function receiving two arguments: `req`, the HTTP request, and the original `filename` of the uploaded file. It should return a string `key`. The `req` parameter can be used to upload to a user-specific folder in your bucket, for example:
+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 two arguments: `req`, the HTTP request, and the original `filename` of the uploaded file. It should return a string `key`. The `req` parameter can be used to upload to a user-specific folder in your bucket, for example:
 
 ```js
 app.use(authenticationMiddleware)
@@ -265,13 +265,13 @@ app.use(uppy.app({
 
 The default value simply returns `filename`, so all files will be uploaded to the root of the bucket as their original file name.
 
-### Run in Kubernetes
+### Running in Kubernetes
 
 We have [a detailed guide on running Uppy Server in Kubernetes](https://github.com/transloadit/uppy-server/blob/master/KUBERNETES.md) for you, that’s how we currently run our example server at http://server.uppy.io.
 
-### Adding Custom Providers
+### Adding custom providers
 
-As of now, Uppy Server supports **Google Drive**, **Dropbox**, **Instagram**, and **Url** (remote urls) out of the box, but you may also choose to add your 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.
+As of now, Uppy Server supports **Google Drive**, **Dropbox**, **Instagram**, and **URL** (remote urls) 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.
 
 ```javascript
 let options = {
@@ -293,26 +293,26 @@ let options = {
 uppy.app(options)
 ```
 
-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.
+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 Uppy Server, 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).
+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 whose 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's some data you need in there).
-  - `done (err, response, body)` - the callback that should be called when the request to your provider is done. As the signature indicates the following data should be passed along to the callback `err`, `response`, and `body`.
+    - 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, response, body)` - 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`, `response`, and `body`.
 2. `download (options, onData, onResponse)` - 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.
+  - `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.
   - `onData (chunk)` - a callback that should be called with each data chunk received on download. This is useful if the size of the downloaded file can be pre-determined. This would allow for pipelined upload of the file (to the desired destination), while the download is still going on.
   - `onResponse (response)` - if the size of the downloaded file can not be pre-determined by Uppy Server, then this callback should be called in place of the `onData` callback. This callback would be called after the download is done, and would take the downloaded data (response) as the argument.
 
 ## Development
 
-1\. To setup Uppy Server for local development, please clone the repo and install like so:
+1\. To set up Uppy Server for local development, please clone the repo and install, like so:
 
 ```bash
 git clone https://github.com/transloadit/uppy-server && cd uppy-server && npm install