Fix hardcoded port, readme

samples/mqtt-client/README.md

@@ -1,8 +1,18 @@
-This is a simple OPC UA client hooked up to an MQTT client. It demonstrates a simple bridging app 
+This is a simple OPC UA client hooked up to an MQTT client. It demonstrates how you might write a bridging app 
 that subscribes to variables from an OPC server and publishes them to an MQTT broker.
 
-The default MQTT server broker.hivemq.com:1883 which you can observe from the client:
+To run the sample:
+
+1. Run either simple-server or 3rd-party/node-opcua/server.js in one console
+2. Run mqtt-client in another
+
+This will subscribe to some nodes on the server and publish them to a MQTT broker, (default broker.hivemq.com:1883).
+
+e.g. when node "ns=2;s=v1" changes, it publishes it's value to the "opcua-rust/mqtt-client/2/v1" topic on the server.
+
+You can observe happening by running another MQTT client that subscribes to this same topic. The easiest way is this:
 
 1. Open http://www.hivemq.com/demos/websocket-client/
-2. Connect with the default values
-3. Subscribe to opcua-rust/# 
+2. Click "Connect" to the broker with the pre-filled values
+3. Click "Add New Topic Subscription", enter "opcua-rust/mqtt-client/#" as the topic and click "Subscribe" 
+4. You should see messages arrive that were published

samples/mqtt-client/src/main.rs

@@ -1,14 +1,17 @@
 //! This is a sample OPC UA Client that connects to the specified server, fetches some
 //! values before exiting.
+#[macro_use]
 extern crate clap;
 extern crate rumqtt;
 
 extern crate opcua_client;
 extern crate opcua_console_logging;
 
-use std::sync::{Arc, Mutex, RwLock, mpsc};
-use std::path::PathBuf;
-use std::thread;
+use std::{
+    path::PathBuf,
+    sync::{Arc, Mutex, RwLock, mpsc},
+    thread,
+};
 
 use rumqtt::{MqttClient, MqttOptions, QoS};
 use clap::{App, Arg};
@@ -53,7 +56,7 @@ fn main() {
         .get_matches();
 
     let mqtt_host = m.value_of("host").unwrap().to_string();
-    let mqtt_port = 1883; // value_t_or_exit!(m, "port", u16);
+    let mqtt_port = value_t_or_exit!(m, "port", u16);
     let config_file = m.value_of("config").unwrap().to_string();
     let endpoint_id = m.value_of("id").unwrap().to_string();
 

tools/certificate-creator/src/main.rs

@@ -1,3 +1,4 @@
+#[macro_use]
 extern crate clap;
 extern crate opcua_core;