鸿蒙之连接MQTT

移植MQTT

鸿蒙系统中通过移植第3方软件包 paho mqtt去实现MQTT协议功能

首先下载MQTT移植文件

https://download.csdn.net/download/qq_44629109/79195528

我们在鸿蒙系统源码的 third_party 文件夹下创建一个 pahomqtt 文件夹，然后把解压后的所有文件都拷贝到 pahomqtt 文件夹下

下一步，我们在pahomqtt 文件夹下面新建BUILD.gn文件，用来构建编译。其内容如下

import("//build/lite/config/component/lite_component.gni")
import("//build/lite/ndk/ndk.gni")

config("pahomqtt_config") {
    include_dirs = [
        "MQTTPacket/src",
        "MQTTClient-C/src",
        "MQTTClient-C/src/liteOS",
        "//kernel/liteos_m/components/cmsis/2.0",
    ]
}

pahomqtt_sources = [
"MQTTClient-C/src/liteOS/MQTTLiteOS.c",
"MQTTClient-C/src/MQTTClient.c",

"MQTTPacket/src/MQTTConnectClient.c",
"MQTTPacket/src/MQTTConnectServer.c",
"MQTTPacket/src/MQTTDeserializePublish.c",
"MQTTPacket/src/MQTTFormat.c",
"MQTTPacket/src/MQTTPacket.c",
"MQTTPacket/src/MQTTSerializePublish.c",
"MQTTPacket/src/MQTTSubscribeClient.c",
"MQTTPacket/src/MQTTSubscribeServer.c",
"MQTTPacket/src/MQTTUnsubscribeClient.c",
"MQTTPacket/src/MQTTUnsubscribeServer.c",
]

lite_library("pahomqtt_static") {
    target_type = "static_library"
    sources = pahomqtt_sources
    public_configs = [ ":pahomqtt_config" ]
}

lite_library("pahomqtt_shared") {
    target_type = "shared_library"
    sources = pahomqtt_sources
    public_configs = [ ":pahomqtt_config" ]
}

ndk_lib("pahomqtt_ndk") {
    if (board_name != "hi3861v100") {
        lib_extension = ".so"
        deps = [
            ":pahomqtt_shared"
        ]
    } else {
        deps = [
            ":pahomqtt_static"
        ]
    }
    head_files = [
        "//third_party/pahomqtt"
    ]
}

打开vendor\hisi\hi3861\hi3861\BUILD.gn 文件，

在lite_component(“sdk”) 中增加

“//third_party/pahomqtt:pahomqtt_static”

鸿蒙之连接MQTT_#include

修改文件

打开 third_party\pahomqtt\MQTTPacket\samples\transport.c 文件，这个文件也是我们主要移植的文件，我们需要实现 socket相关的操作，包括发送、接收数据。其实移植就3步。

（1）在transport.c导入三个头文件

#include "lwip/ip_addr.h"
#include "lwip/sockets.h"
#include "lwip/netifapi.h"

（2）修改 transport_sendPacketBuffer 函数：

int transport_sendPacketBuffer(int sock, unsigned char* buf, int buflen)
{
  int rc = 0;
  rc = send(sock, buf, buflen, 0);
  return rc;
}

（3）修改 transport_close 函数：

int transport_close(int sock)
{
int rc;
  rc = shutdown(sock, SHUT_WR);
  rc = recv(sock, NULL, (size_t)0, 0);
  rc = lwip_close(sock);
 return rc;
 }

编写测试代码

在./applications/sample/wifi-iot/app路径下新建一个目录（或一套目录结构），用于存放业务源码文件。

其中有四个文件：

  1. BUILD.gn
static_library("mqtt_test_at") {
    sources = [
        "mqtt_test.c",
        "at_entry.c"
    ]
 
    include_dirs = [
        "//utils/native/lite/include",
        "//kernel/liteos_m/components/cmsis/2.0",
        "//base/iot_hardware/interfaces/kits/wifiiot_lite",
        "//vendor/hisi/hi3861/hi3861/third_party/lwip_sack/include",
        "//foundation/communication/interfaces/kits/wifi_lite/wifiservice",
        "//third_party/pahomqtt/MQTTPacket/src",
        "//third_party/pahomqtt/MQTTPacket/samples",
        "//vendor\hisi\hi3861\hi3861\components\at\src"
    ]
}
  1. at_entry.c
#include <stdio.h>
#include <unistd.h>
#include "ohos_init.h"
#include "cmsis_os2.h"
#include <unistd.h>
#include <at.h>
#include <hi_at.h>
#include "hi_wifi_api.h"
#include "mqtt_test.h"
void mqtt_test_thread(void * argv)
{
    argv = argv;
    mqtt_test();
}
hi_u32 at_exe_mqtt_test_cmd(void)
{
    osThreadAttr_t attr;
    attr.name = "wifi_config_thread";
    attr.attr_bits = 0U;
    attr.cb_mem = NULL;
    attr.cb_size = 0U;
    attr.stack_mem = NULL;
    attr.stack_size = 4096;
    attr.priority = 36;

    if (osThreadNew((osThreadFunc_t)mqtt_test_thread, NULL, &attr) == NULL) {
        printf("[LedExample] Falied to create LedTask!\n");
    }
    AT_RESPONSE_OK;
    return HI_ERR_SUCCESS;
}
const at_cmd_func g_at_mqtt_func_tbl[] = {
    {"+MQTTTEST", 9, HI_NULL, HI_NULL, HI_NULL, (at_call_back_func)at_exe_mqtt_test_cmd},
};
void AtExampleEntry(void)
{
    hi_at_register_cmd(g_at_mqtt_func_tbl, sizeof(g_at_mqtt_func_tbl)/sizeof(g_at_mqtt_func_tbl[0]));
}
SYS_RUN(AtExampleEntry);
  1. mqtt_test.c
#include <stdio.h>

#include <unistd.h>

#include "ohos_init.h"
#include "cmsis_os2.h"

#include <unistd.h>
#include "hi_wifi_api.h"
//#include "wifi_sta.h"
#include "lwip/ip_addr.h"
#include "lwip/netifapi.h"

#include "lwip/sockets.h"

#include "MQTTPacket.h"
#include "transport.h"

int toStop = 0;

int mqtt_connect(void)
{
    MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
    int rc = 0;
    int mysock = 0;
    unsigned char buf[200];
    int buflen = sizeof(buf);
    int msgid = 1;
    MQTTString topicString = MQTTString_initializer;
    int req_qos = 0;
    char* payload = "hello HarmonyOS";
    int payloadlen = strlen(payload);
    int len = 0;
    char *host = "MQTT服务器的ip地址";
    int port = 1883;


    mysock = transport_open(host, port);
    if(mysock < 0)
        return mysock;

    printf("Sending to hostname %s port %d\n", host, port);

    data.clientID.cstring = "me";
    data.keepAliveInterval = 20;
    data.cleansession = 1;
    data.username.cstring = "testuser";
    data.password.cstring = "testpassword";

    len = MQTTSerialize_connect(buf, buflen, &data);
    rc = transport_sendPacketBuffer(mysock, buf, len);

    /* wait for connack */
    if (MQTTPacket_read(buf, buflen, transport_getdata) == CONNACK)
    {
        unsigned char sessionPresent, connack_rc;

        if (MQTTDeserialize_connack(&sessionPresent, &connack_rc, buf, buflen) != 1 || connack_rc != 0)
        {
            printf("Unable to connect, return code %d\n", connack_rc);
            goto exit;
        }
    }
    else
        goto exit;

    /* subscribe */
    topicString.cstring = "substopic";
    len = MQTTSerialize_subscribe(buf, buflen, 0, msgid, 1, &topicString, &req_qos);
    rc = transport_sendPacketBuffer(mysock, buf, len);
    if (MQTTPacket_read(buf, buflen, transport_getdata) == SUBACK)  /* wait for suback */
    {
        unsigned short submsgid;
        int subcount;
        int granted_qos;

        rc = MQTTDeserialize_suback(&submsgid, 1, &subcount, &granted_qos, buf, buflen);
        if (granted_qos != 0)
        {
            printf("granted qos != 0, %d\n", granted_qos);
            goto exit;
        }
    }
    else
        goto exit;

    /* loop getting msgs on subscribed topic */
    topicString.cstring = "pubtopic";
    while (!toStop)
    {
        /* transport_getdata() has a built-in 1 second timeout,
        your mileage will vary */
        if (MQTTPacket_read(buf, buflen, transport_getdata) == PUBLISH)
        {
            unsigned char dup;
            int qos;
            unsigned char retained;
            unsigned short msgid;
            int payloadlen_in;
            unsigned char* payload_in;
            int rc;
            MQTTString receivedTopic;
            rc = MQTTDeserialize_publish(&dup, &qos, &retained, &msgid, &receivedTopic,
                    &payload_in, &payloadlen_in, buf, buflen);
            printf("message arrived %.*s\n", payloadlen_in, payload_in);

            rc = rc;
        }

        printf("publishing reading\n");
        len = MQTTSerialize_publish(buf, buflen, 0, 0, 0, 0, topicString, (unsigned char*)payload, payloadlen);
        rc = transport_sendPacketBuffer(mysock, buf, len);
    }

    printf("disconnecting\n");
    len = MQTTSerialize_disconnect(buf, buflen);
    rc = transport_sendPacketBuffer(mysock, buf, len);
exit:
    transport_close(mysock);

    rc = rc;

    return 0;
}


void mqtt_test(void)
{
    mqtt_connect();
}
  1. mqtt_test.h
#ifndef __MQTT_TEST_H__
#define __MQTT_TEST_H__
void mqtt_test(void);
#endif /* __MQTT_TEST_H__ */

烧录进开发板

运行

首先打开MQTT服务器

首先通过AT指令进行联网。

在串口调试助手发送”AT+STARTSTA“， 启动STA模式。

发送” AT+CONN=“BAHUYANG”,2,“123456789” “ 连接指定AP，其中SSID/PASSWORD为待连接的热点名称和密码。

发送”AT+STASTAT” ，查看连接结果。

然后我们输入我们的 MQTT测试的AT指令： AT+MQTTTEST

可以从串口调试助手上看到如下图。

鸿蒙之连接MQTT_harmonyos_02

然后查看MQTT客户端软件，可以看到右边已经有接收MQTT信息了，主题是 pubtopic，消息内容为 hello HarmonyOS ! ，说明实验成功。

鸿蒙之连接MQTT_物联网_03

后续

可以关注我的程序设计专栏。

关注微信公众号

鸿蒙之连接MQTT_#include_04

编写不易，感谢支持。