Added ability to limit specific socket names

Author: daniel-thm

README.md

@@ -19,7 +19,7 @@ A simple example of using [Node.js](https://nodejs.org/) to send Growl-style mes
 
 ### TODO
 
-- [ ] Add ability to limit specific socket names
+- [x] Add ability to limit specific socket names
 - [x] Add connect/disconnect state to demo page
 - [x] Add field to demo page to submit message
 - [x] Add Growl-style example
@@ -60,6 +60,9 @@ If you'd like to have a different [configuration file](https://github.com/lorenw
     "api_keys": [
         "abc123def",
         "tuv456xyz"
+    ],
+    "sockets": [
+        "my-socket-name"
     ]
 }
 ```

config/default.json

@@ -7,5 +7,6 @@
         "origins": [ "*" ]
     },
     "demo_page": true,
-    "api_keys": []
+    "api_keys": [],
+    "sockets": []
 }

server.js

@@ -36,6 +36,8 @@ server.post( '/send/:socket', function( req, res, next ) {
 
     if( config.get( 'api_keys' ).length && ( typeof req.query.api_key === 'undefined' || !config.get( 'api_keys' ).includes( req.query.api_key ) ) ) {
         next( new errors.BadRequestError( 'Invalid API key' ) );
+    } else if( config.get( 'sockets' ).length && !config.get( 'sockets' ).includes( req.params.socket ) ) {
+        next( new errors.BadRequestError( 'Invalid socket name' ) );
     } else {
         io.emit( req.params.socket, req.body );
         res.send( req.body );