将stm32单片机接收到的GPS信息发送到阿里云设备库函数版

发送 GPS 信息到阿里云设备需要借助 MQTT 协议进行通信。以下是基于阿里云物联网平台 MQTT 协议的示例代码，其中 `mqtt_client` 是阿里云物联网平台提供的 MQTT 客户端库。

#include "mqtt_client.h"

// 阿里云物联网平台的参数
#define PRODUCT_KEY     "your_product_key"
#define DEVICE_NAME     "your_device_name"
#define DEVICE_SECRET   "your_device_secret"
#define TOPIC           "/your_topic"

// MQTT 客户端实例
mqtt_client_t mqtt_client;

// MQTT 连接回调函数
static void mqtt_connection_cb(mqtt_client_t *client, void *arg, mqtt_connection_status_t status)
{
    if (status == MQTT_CONNECTION_ACCEPTED) {
        printf("MQTT connected\n");
        // 订阅主题
        mqtt_subscribe(client, TOPIC, 0);
    } else {
        printf("MQTT connection failed\n");
    }
}

// MQTT 接收消息回调函数
static void mqtt_message_cb(mqtt_client_t *client, void *arg, const mqtt_message_t *message)
{
    printf("Received message: %.*s\n", (int)message->payload_len, (char *)message->payload);
}

// 发送 GPS 信息到阿里云设备
void send_gps_info_to_aliyun(float latitude, float longitude)
{
    char payload[128];
    int payload_len = snprintf(payload, sizeof(payload), "{\"latitude\":%.6f,\"longitude\":%.6f}", latitude, longitude);

    // MQTT 连接参数
    mqtt_connect_opt_t connect_opt = {
        .clean_session = 0,
        .client_id = DEVICE_NAME,
        .username = PRODUCT_KEY "&" DEVICE_NAME,
        .password = mqtt_sign(PRODUCT_KEY, DEVICE_NAME, DEVICE_SECRET, HAL_GetTimeMs()),
        .keep_alive = 60,
        .will_topic = NULL,
        .will_message = NULL,
        .will_retain = 0,
        .will_qos = 0,
    };

    // MQTT 客户端参数
    mqtt_client_t mqtt_client = {
        .host = PRODUCT_KEY ".iot-as-mqtt.cn-shanghai.aliyuncs.com",
        .port = 1883,
        .client_opt = &connect_opt,
        .command_timeout_ms = 5000,
        .keep_alive_interval_ms = 10000,
        .event_handle.hook = NULL,
        .event_handle.context = NULL,
        .connection_cb = mqtt_connection_cb,
        .message_cb = mqtt_message_cb,
    };

    // 连接 MQTT 服务器
    mqtt_connect(&mqtt_client);

    // 发布消息
    mqtt_publish(&mqtt_client, TOPIC, payload, payload_len, 0, 0);

    // 断开 MQTT 连接
    mqtt_disconnect(&mqtt_client);
}

注意，上述代码仅为示例代码，需要根据实际情况进行修改。其中 `PRODUCT_KEY`、`DEVICE_NAME`、`DEVICE_SECRET` 和 `TOPIC` 需要替换为自己的阿里云物联网平台参数。此外，`send_gps_info_to_aliyun` 函数需要在接收到 GPS 信息后调用。