Adding publish and subscribe atomic client examples

Author: embhorn

.gitignore

@@ -78,6 +78,8 @@ examples/sn-client/sn-client_qos-1
 examples/sn-client/sn-multithread
 examples/multithread/multithread
 examples/wiot/wiot
+examples/pub-sub/pub
+examples/pub-sub/sub
 
 # eclipse
 .cproject

CMakeLists.txt

@@ -147,6 +147,8 @@ if (WOLFMQTT_EXAMPLES)
     add_mqtt_example(azureiothub azure/azureiothub.c)
     add_mqtt_example(fwpush firmware/fwpush.c)
     add_mqtt_example(fwclient firmware/fwclient.c)
+    add_mqtt_example(mqtt-pub pub-sub/mqtt-pub.c)
+    add_mqtt_example(mqtt-pub pub-sub/mqtt-sub.c)
 endif()
 
 ####################################################

README.md

@@ -213,6 +213,13 @@ WolfGatewayQoS-1,wolfMQTT/example/testTopic, 1
 ### Multithread Example
 This example exercises the multithreading capabilities of the client library. The client implements two tasks: one that publishes to the broker; and another that waits for messages from the broker. The publish thread is created `NUM_PUB_TASKS` times (10 by default) and sends unique messages to the broker. This feature is enabled using the `--enable-mt` configuration option. The example is located in `/examples/multithread/`.
 
+### Atomic publish and subscribe examples
+In the `examples/pub-sub` folder, there are two simple client examples:
+* mqtt-pub - publishes to a topic
+* mqtt-sub - subscribes to a topic and waits for messages
+
+These examples are useful for quickly testing or scripting.
+
 ## Example Options
 The command line examples can be executed with optional parameters. To see a list of the available parameters, add the `-?`
 

examples/include.am

@@ -13,7 +13,9 @@ noinst_PROGRAMS += examples/mqttclient/mqttclient \
                    examples/multithread/multithread \
                    examples/sn-client/sn-client \
                    examples/sn-client/sn-client_qos-1 \
-                   examples/sn-client/sn-multithread
+                   examples/sn-client/sn-multithread \
+                   examples/pub-sub/mqtt-pub \
+                   examples/pub-sub/mqtt-sub
 
 noinst_HEADERS +=  examples/mqttclient/mqttclient.h \
                    examples/mqttsimple/mqttsimple.h \
@@ -28,7 +30,8 @@ noinst_HEADERS +=  examples/mqttclient/mqttclient.h \
                    examples/mqttport.h \
                    examples/nbclient/nbclient.h \
                    examples/multithread/multithread.h \
-                   examples/sn-client/sn-client.h
+                   examples/sn-client/sn-client.h \
+                   examples/pub-sub/mqtt-pub-sub.h
 
 # MQTT Client Example
 examples_mqttclient_mqttclient_SOURCES      = examples/mqttclient/mqttclient.c \
@@ -127,6 +130,21 @@ examples_sn_client_sn_multithread_SOURCES       = examples/sn-client/sn-multithr
 examples_sn_client_sn_multithread_LDADD         = src/libwolfmqtt.la
 examples_sn_client_sn_multithread_DEPENDENCIES  = src/libwolfmqtt.la
 examples_sn_client_sn_multithread_CPPFLAGS      = -I$(top_srcdir)/examples $(AM_CPPFLAGS)
+
+# MQTT pub and sub clients
+examples_pub_sub_mqtt_pub_SOURCES      = examples/pub-sub/mqtt-pub.c \
+                                         examples/mqttnet.c \
+                                         examples/mqttexample.c
+examples_pub_sub_mqtt_pub_LDADD        = src/libwolfmqtt.la
+examples_pub_sub_mqtt_pub_DEPENDENCIES = src/libwolfmqtt.la
+examples_pub_sub_mqtt_pub_CPPFLAGS     = -I$(top_srcdir)/examples $(AM_CPPFLAGS)
+
+examples_pub_sub_mqtt_sub_SOURCES      = examples/pub-sub/mqtt-sub.c \
+                                         examples/mqttnet.c \
+                                         examples/mqttexample.c
+examples_pub_sub_mqtt_sub_LDADD        = src/libwolfmqtt.la
+examples_pub_sub_mqtt_sub_DEPENDENCIES = src/libwolfmqtt.la
+examples_pub_sub_mqtt_sub_CPPFLAGS     = -I$(top_srcdir)/examples $(AM_CPPFLAGS)
 endif
 
 
@@ -145,6 +163,8 @@ dist_example_DATA+= examples/multithread/multithread.c
 dist_example_DATA+= examples/sn-client/sn-client.c
 dist_example_DATA+= examples/sn-client/sn-client_qos-1.c
 dist_example_DATA+= examples/sn-client/sn-multithread.c
+dist_example_DATA+= examples/pub-sub/mqtt-pub.c
+dist_example_DATA+= examples/pub-sub/mqtt-sub.c
 
 DISTCLEANFILES+=   examples/mqttclient/.libs/mqttclient \
                    examples/firmware/.libs/fwpush \
@@ -156,7 +176,9 @@ DISTCLEANFILES+=   examples/mqttclient/.libs/mqttclient \
                    examples/multithread/.libs/multithread \
                    examples/sn-client/.libs/sn-client \
                    examples/sn-client/.libs/sn-client_qos-1 \
-                   examples/sn-client/.libs/sn-multithread
+                   examples/sn-client/.libs/sn-multithread \
+                   examples/pub-sub/mqtt-pub \
+                   examples/pub-sub/mqtt-sub
 
 EXTRA_DIST+=       examples/mqttuart.c \
                    examples/publish.dat \

examples/mqttclient/mqttclient.c

@@ -648,9 +648,6 @@ int mqttclient_test(MQTTCtx *mqttCtx)
 
     PRINTF("MQTT Disconnect: %s (%d)",
         MqttClient_ReturnCodeToString(rc), rc);
-    if (rc != MQTT_CODE_SUCCESS) {
-        goto disconn;
-    }
 
     rc = MqttClient_NetDisconnect(&mqttCtx->client);
 

examples/mqttexample.c

@@ -247,6 +247,9 @@ void mqtt_show_usage(MQTTCtx* mqttCtx)
 #endif
     PRINTF("-T          Test mode");
     PRINTF("-f <file>   Use file contents for publish");
+    if (!mqttCtx->debug_on) {
+        PRINTF("-d          Enable example debug messages");
+    }
 }
 
 void mqtt_init_ctx(MQTTCtx* mqttCtx)
@@ -259,6 +262,7 @@ void mqtt_init_ctx(MQTTCtx* mqttCtx)
     mqttCtx->client_id = kDefClientId;
     mqttCtx->topic_name = kDefTopicName;
     mqttCtx->cmd_timeout_ms = DEFAULT_CMD_TIMEOUT_MS;
+    mqttCtx->debug_on = 1;
 #ifdef WOLFMQTT_V5
     mqttCtx->max_packet_size = DEFAULT_MAX_PKT_SZ;
     mqttCtx->topic_alias = 1;
@@ -286,7 +290,7 @@ int mqtt_parse_args(MQTTCtx* mqttCtx, int argc, char** argv)
         #define MQTT_V5_ARGS ""
     #endif
 
-    while ((rc = mygetopt(argc, argv, "?h:p:q:sk:i:lu:w:m:n:C:Tf:rt" \
+    while ((rc = mygetopt(argc, argv, "?h:p:q:sk:i:lu:w:m:n:C:Tf:rtd" \
             MQTT_TLS_ARGS MQTT_V5_ARGS)) != -1) {
         switch ((char)rc) {
         case '?' :
@@ -364,6 +368,10 @@ int mqtt_parse_args(MQTTCtx* mqttCtx, int argc, char** argv)
             mqttCtx->use_tls = 1;
             break;
 
+        case 'd':
+            mqttCtx->debug_on = 1;
+            break;
+
     #ifdef ENABLE_MQTT_TLS
         case 'A':
             mTlsCaFile = myoptarg;

examples/mqttexample.h

@@ -168,6 +168,7 @@ typedef struct _MQTTCtx {
 #endif
     byte    clean_session;
     byte    test_mode;
+    byte    debug_on:1; /* enable debug messages in example */
 #ifdef WOLFMQTT_V5
     byte    subId_not_avail; /* Server property */
     byte    enable_eauth; /* Enhanced authentication */

examples/mqttnet.c

@@ -76,8 +76,10 @@ static int NetConnect(void *context, const char* host, word16 port,
 
     switch (sock->stat) {
     case SOCK_BEGIN:
-        PRINTF("NetConnect: Host %s, Port %u, Timeout %d ms, Use TLS %d",
-            host, port, timeout_ms, mqttCtx->use_tls);
+        if (mqttCtx->debug_on) {
+            PRINTF("NetConnect: Host %s, Port %u, Timeout %d ms, Use TLS %d",
+                host, port, timeout_ms, mqttCtx->use_tls);
+        }
 
         hostIp = FreeRTOS_gethostbyname_a(host, NULL, 0, 0);
         if (hostIp == 0)
@@ -255,9 +257,10 @@ static int NetConnect(void *context, const char* host, word16 port,
     switch(sock->stat) {
         case SOCK_BEGIN:
         {
-            PRINTF("NetConnect: Host %s, Port %u, Timeout %d ms, Use TLS %d",
-                host, port, timeout_ms, mqttCtx->use_tls);
-
+            if (mqttCtx->debug_on) {
+                PRINTF("NetConnect: Host %s, Port %u, Timeout %d ms, "
+                        "Use TLS %d", host, port, timeout_ms, mqttCtx->use_tls);
+            }
             XMEMSET(&hints, 0, sizeof(hints));
             hints.ai_family = AF_INET;
             hints.ai_socktype = SOCK_STREAM;
@@ -446,8 +449,10 @@ static int NetConnect(void *context, const char* host, word16 port,
     switch(sock->stat) {
         case SOCK_BEGIN:
         {
-            PRINTF("NetConnect: Host %s, Port %u, Timeout %d ms, Use TLS %d",
-                host, port, timeout_ms, mqttCtx->use_tls);
+            if (mqttCtx->debug_on) {
+                PRINTF("NetConnect: Host %s, Port %u, Timeout %d ms, "
+                        "Use TLS %d", host, port, timeout_ms, mqttCtx->use_tls);
+            }
 
             XMEMSET(&hints, 0, sizeof(hints));
             hints.ai_family = AF_INET;

examples/pub-sub/mqtt-pub-sub.h

@@ -0,0 +1,38 @@
+/* mqtt-pub-sub
+ *
+ * Copyright (C) 2006-2023 wolfSSL Inc.
+ *
+ * This file is part of wolfMQTT.
+ *
+ * wolfMQTT is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfMQTT is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+
+#ifndef WOLFMQTT_PUB_SUB_H
+#define WOLFMQTT_PUB_SUB_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* Exposed functions */
+int pub_client(MQTTCtx *mqttCtx);
+int sub_client(MQTTCtx *mqttCtx);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* WOLFMQTT_PUB_SUB_H */