add test connection to the nats server.

src/CMakeLists.txt

@@ -19,6 +19,7 @@ add_executable (domo-iot ${source_files})
 
 target_link_libraries (domo-iot 
 	LINK_PUBLIC
+	nats
 	rt
 )
 

src/domo-iot.c

@@ -27,6 +27,21 @@
 
 #include <nats.h>
 
+static void
+onMsg(natsConnection *nc, natsSubscription *sub, natsMsg *msg, void *closure)
+{
+    printf("Received msg: %s - %.*s\n",
+           natsMsg_GetSubject(msg),
+           natsMsg_GetDataLength(msg),
+           natsMsg_GetData(msg));
+
+    // Need to destroy the message!
+    natsMsg_Destroy(msg);
+
+    // Notify the main thread that we are done.
+    *(bool *)(closure) = true;
+}
+
 /*!  ----------------------------------------------------------------------------
  *  @fn main
  *
@@ -34,12 +49,41 @@
  */
 int main(int argc, char *argv[])
 {
-    natsConnection      *conn = NULL;
-    natsSubscription    *sub  = NULL;
-    natsStatus          s;
-    volatile bool       done  = false;
+    natsConnection *conn = NULL;
+    natsSubscription *sub = NULL;
+    natsStatus s;
+    volatile bool done = false;
 
     printf("Listening on subject 'foo'\n");
 
+    // Creates a connection to the default NATS URL
+    s = natsConnection_ConnectTo(&conn, "nats.nadal-fr.com");
+    if (s == NATS_OK)
+    {
+        // Creates an asynchronous subscription on subject "foo".
+        // When a message is sent on subject "foo", the callback
+        // onMsg() will be invoked by the client library.
+        // You can pass a closure as the last argument.
+        s = natsConnection_Subscribe(&sub, conn, "foo", onMsg, (void *)&done);
+    }
+    if (s == NATS_OK)
+    {
+        for (; !done;)
+        {
+            nats_Sleep(100);
+        }
+    }
+
+    // Anything that is created need to be destroyed
+    natsSubscription_Destroy(sub);
+    natsConnection_Destroy(conn);
+
+    // If there was an error, print a stack trace and exit
+    if (s != NATS_OK)
+    {
+        nats_PrintLastErrorStack(stderr);
+        exit(2);
+    }
+
     return 0;
 }