mirror of
https://github.com/cesanta/mongoose.git
synced 2024-12-12 23:49:00 +08:00
89 lines
3.6 KiB
C
89 lines
3.6 KiB
C
// Copyright (c) 2020 Cesanta Software Limited
|
|
// All rights reserved
|
|
//
|
|
// Example MQTT client. It performs the following steps:
|
|
// 1. Connects to the MQTT server specified by `s_url` variable
|
|
// 2. When connected, subscribes to the topic `s_topic`
|
|
// 3. Publishes message `hello` to the `s_topic`
|
|
// 4. Receives that message back from the subscribed topic and exits
|
|
//
|
|
// To enable SSL/TLS for this client, build it like this:
|
|
// make MBEDTLS_DIR=/path/to/your/mbedtls/installation
|
|
|
|
#include "mongoose.h"
|
|
|
|
static const char *s_url = "ws://broker.hivemq.com:8000/mqtt";
|
|
static const char *s_topic = "mg/test";
|
|
|
|
static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
|
|
if (ev == MG_EV_ERROR) {
|
|
// On error, log error message
|
|
LOG(LL_ERROR, ("%p %s", c->fd, (char *) ev_data));
|
|
} else if (ev == MG_EV_CONNECT) {
|
|
// If target URL is SSL/TLS, command client connection to use TLS
|
|
if (mg_url_is_ssl(s_url)) {
|
|
struct mg_tls_opts opts = {.ca = "ca.pem"};
|
|
mg_tls_init(c, &opts);
|
|
}
|
|
} else if (ev == MG_EV_WS_OPEN) {
|
|
// WS connection established. Perform MQTT login
|
|
LOG(LL_INFO, ("Connected to WS. Logging in to MQTT..."));
|
|
struct mg_mqtt_opts opts = {.qos = 1,
|
|
.will_topic = mg_str(s_topic),
|
|
.will_message = mg_str("goodbye")};
|
|
size_t len = c->send.len;
|
|
mg_mqtt_login(c, s_url, &opts);
|
|
mg_ws_wrap(c, c->send.len - len, WEBSOCKET_OP_BINARY);
|
|
} else if (ev == MG_EV_WS_MSG) {
|
|
struct mg_mqtt_message mm;
|
|
struct mg_ws_message *wm = (struct mg_ws_message *) ev_data;
|
|
LOG(LL_INFO, ("GOT %d bytes WS msg", (int) wm->data.len));
|
|
while ((mg_mqtt_parse((uint8_t *) wm->data.ptr, wm->data.len, &mm)) == 0) {
|
|
switch (mm.cmd) {
|
|
case MQTT_CMD_CONNACK:
|
|
mg_call(c, MG_EV_MQTT_OPEN, &mm.ack);
|
|
if (mm.ack == 0) {
|
|
struct mg_str topic = mg_str(s_topic), data = mg_str("hello");
|
|
size_t len = c->send.len;
|
|
LOG(LL_INFO, ("CONNECTED to %s", s_url));
|
|
mg_mqtt_sub(c, &topic, 1);
|
|
mg_ws_wrap(c, len, WEBSOCKET_OP_BINARY);
|
|
LOG(LL_INFO, ("SUBSCRIBED to %.*s", (int) topic.len, topic.ptr));
|
|
mg_mqtt_pub(c, &topic, &data, 1, false);
|
|
LOG(LL_INFO, ("PUBSLISHED %.*s -> %.*s", (int) data.len, data.ptr,
|
|
(int) topic.len, topic.ptr));
|
|
len = mg_ws_wrap(c, c->send.len - len, WEBSOCKET_OP_BINARY);
|
|
} else {
|
|
LOG(LL_ERROR, ("%lu MQTT auth failed, code %d", c->id, mm.ack));
|
|
c->is_closing = 1;
|
|
}
|
|
break;
|
|
case MQTT_CMD_PUBLISH: {
|
|
LOG(LL_DEBUG, ("%lu [%.*s] -> [%.*s]", c->id, (int) mm.topic.len,
|
|
mm.topic.ptr, (int) mm.data.len, mm.data.ptr));
|
|
LOG(LL_INFO, ("RECEIVED %.*s <- %.*s", (int) mm.data.len, mm.data.ptr,
|
|
(int) mm.topic.len, mm.topic.ptr));
|
|
c->is_closing = 1;
|
|
break;
|
|
}
|
|
}
|
|
wm->data.ptr += mm.dgram.len;
|
|
wm->data.len -= mm.dgram.len;
|
|
}
|
|
}
|
|
|
|
if (ev == MG_EV_ERROR || ev == MG_EV_CLOSE) {
|
|
*(bool *) fn_data = true; // Signal that we're done
|
|
}
|
|
}
|
|
|
|
int main(void) {
|
|
struct mg_mgr mgr; // Event manager
|
|
bool done = false; // Event handler flips it to true when done
|
|
mg_mgr_init(&mgr); // Initialise event manager
|
|
mg_ws_connect(&mgr, s_url, fn, &done, NULL); // Create client connection
|
|
while (done == false) mg_mgr_poll(&mgr, 1000); // Event loop
|
|
mg_mgr_free(&mgr); // Finished, cleanup
|
|
return 0;
|
|
}
|