Added properties indexer w/ example. Now uint8_t prints properly (as …

…unsigned)

examples/async_consume_v5.cpp

@@ -43,7 +43,8 @@ using namespace std;
 const string DFLT_SERVER_URI{"mqtt://localhost:1883"};
 const string CLIENT_ID{"PahoCppAsyncConsumeV5"};
 
-const string TOPIC{"hello"};
+// const string TOPIC{"hello"};
+const string TOPIC{"#"};
 const int QOS = 1;
 
 /////////////////////////////////////////////////////////////////////////////
@@ -92,7 +93,7 @@ int main(int argc, char* argv[])
         // We'll signal the consumer to exit from another thread.
         // (just to show that we can)
         thread([cli] {
-            this_thread::sleep_for(10s);
+            this_thread::sleep_for(60s);
             cout << "\nClosing the consumer." << endl;
             cli->stop_consuming();
         }).detach();
@@ -111,8 +112,19 @@ int main(int argc, char* argv[])
 
                 if (const auto* p = evt.get_message_if()) {
                     auto& msg = *p;
-                    if (msg)
-                        cout << msg->get_topic() << ": " << msg->to_string() << endl;
+                    if (!msg)
+                        continue;
+
+                    cout << msg->get_topic() << ": " << msg->to_string();
+
+                    const auto& props = msg->get_properties();
+                    size_t n = props.size();
+                    if (n != 0) {
+                        cout << "\n  [";
+                        for (size_t i = 0; i < n - 1; ++i) cout << props[i] << ", ";
+                        cout << props[n - 1] << "]";
+                    }
+                    cout << endl;
                 }
                 else if (evt.is_connected()) {
                     cout << "\n*** Connected ***" << endl;

include/mqtt/properties.h

@@ -34,6 +34,7 @@ extern "C" {
 #include <string_view>
 #include <tuple>
 #include <typeinfo>
+#include <stdexcept>
 
 #include "mqtt/buffer_ref.h"
 #include "mqtt/exception.h"
@@ -404,6 +405,24 @@ class properties
      *  	   the list contains any items.
      */
     bool empty() const { return props_.count == 0; }
+    /**
+     * Gets the property at the specified index in the collection.
+     * @param i The index
+     * @return The property at the specified index.
+     */
+    const property operator[](size_t i) const {
+        return property{props_.array[i]};
+    }
+    /**
+     * Gets the property at the specified index in the collection.
+     * @param i The index
+     * @return The property at the specified index.
+     */
+    const property at(size_t i) const {
+        if (i < size_t(props_.count))
+            return property{props_.array[i]};
+        throw std::out_of_range{"propery index"};
+    }
     /**
      * Gets the numbers of property items in the list.
      * @return The number of property items in the list.

src/properties.cpp

@@ -201,7 +201,7 @@ std::ostream& operator<<(std::ostream& os, const property& prop)
 
     switch (::MQTTProperty_getType(MQTTPropertyCodes(prop.type()))) {
         case MQTTPROPERTY_TYPE_BYTE:
-            os << get<uint8_t>(prop);
+            os << unsigned(get<uint8_t>(prop));
             break;
 
         case MQTTPROPERTY_TYPE_TWO_BYTE_INTEGER: