Merge branch 'master' into breaking-changes

Author: mikuso

README.md

@@ -247,7 +247,7 @@ await cli.connect();
 
 - `options` {Object}
   - `protocols` {Array<String>} - Array of subprotocols supported by this server. Can be overridden in an [auth](#serverauthcallback) callback. Defaults to `[]`.
-  - `callTimeoutMs` {Number} - Milliseconds to wait before unanswered outbound calls are rejected automatically. Defaults to `60000`.
+  - `callTimeoutMs` {Number} - Milliseconds to wait before unanswered outbound calls are rejected automatically. Defaults to `30000`.
   - `pingIntervalMs` {Number} - Milliseconds between WebSocket pings to connected clients. Defaults to `30000`.
   - `respondWithDetailedErrors` {Boolean} - Specifies whether to send detailed errors (including stack trace) to remote party upon an error being thrown by a handler. Defaults to `false`.
   - `callConcurrency` {Number} - The number of concurrent in-flight outbound calls permitted at any one time. Additional calls are queued. (There is no limit on inbound calls.) Defaults to `1`.

lib/client.js

@@ -642,6 +642,13 @@ class RPCClient extends EventEmitter {
 
     _onMessage(buffer) {
         const message = buffer.toString('utf8');
+
+        if (!message.length) {
+            // ignore empty messages
+            // for compatibility with some particular charge point vendors (naming no names)
+            return;
+        }
+
         this.emit('message', {message, outbound: false});
 
         let msgId = '-1';

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "ocpp-rpc",
-  "version": "1.7.3",
+  "version": "1.7.4",
   "description": "A client & server implementation of the WAMP-like RPC-over-websocket system defined in the OCPP protcols (e.g. OCPP1.6-J and OCPP2.0.1).",
   "main": "index.js",
   "scripts": {