php实现mqtt发布/发送 消息到主题

摘要：实现发布发送消息到主题是啥我的博客有写这个东西传送门想要实现需要使用到中的函数函数是什么此次使用的是网上开源案例其中使用的是系列函数什么是系列函数大概意思是正如你所指出的，是核心内置的，始终可用，而套接字是很少包含的扩展的一部分。

mqtt是啥?我的博客有写这个东西:传送门

php想要实现mqtt需要使用到php中的socket函数;

socket函数是什么?

此次使用的是网上开源mqtt案例:其中使用的是 stream_socket_xxxx 系列函数

什么是stream_socket_xxxx系列函数

大概意思是:

</>复制代码 
正如你所指出的，"stream"是PHP核心（内置的，始终可用），而"套接字"是很少包含的扩展的一部分。除此之外，它们几乎完全相同。您可以同时使用TCP和UDP两种流，也可以使用阻塞和非阻塞模式，这些模式涵盖了所有用例的99％。
我能想到的唯一常见的例外是ICMP。例如，"ping"。但是，看起来目前还没有一种安全的方式来从PHP执行ICMP。这种调用需要通过套接字扩展来实现SOCK_RAW，这需要执行“root”权限。此外，并非所有路由器都会在TCP，UDP和ICMP之外路由其他数据包类型。这限制了套接字扩展的实用性。

</>复制代码 
/* phpMQTT */
class Mqtt {
    private $socket;             /* holds the socket    */
    private $msgid = 1;            /* counter for message id */
    public $keepalive = 10;        /* default keepalive timmer */
    public $timesinceping;        /* host unix time, used to detect disconects */
    public $topics = array();     /* used to store currently subscribed topics */
    public $debug = false;        /* should output debug messages */
    public $address;            /* broker address */
    public $port;                /* broker port */
    public $clientid;            /* client id sent to brocker */
    public $will;                /* stores the will of the client */
    private $username;            /* stores username */
    private $password;            /* stores password */
    public $cafile;
    function __construct($address, $port, $clientid, $cafile = NULL){
        $this->broker($address, $port, $clientid, $cafile);
    }
    /* sets the broker details */
    function broker($address, $port, $clientid, $cafile = NULL){
        $this->address = $address;
        $this->port = $port;
        $this->clientid = $clientid;
        $this->cafile = $cafile;
    }
    function connect_auto($clean = true, $will = NULL, $username = NULL, $password = NULL){
        while($this->connect($clean, $will, $username, $password)==false){
            sleep(10);
        }
        return true;
    }
    /* connects to the broker
        inputs: $clean: should the client send a clean session flag */
    function connect($clean = true, $will = NULL, $username = NULL, $password = NULL){
        if($will) $this->will = $will;
        if($username) $this->username = $username;
        if($password) $this->password = $password;
        if ($this->cafile) {
            $socketContext = stream_context_create(["ssl" => [
                "verify_peer_name" => true,
                "cafile" => $this->cafile
            ]]);
            $this->socket = stream_socket_client("tls://" . $this->address . ":" . $this->port, $errno, $errstr, 60, STREAM_CLIENT_CONNECT, $socketContext);
        } else {
            $this->socket = stream_socket_client("tcp://" . $this->address . ":" . $this->port, $errno, $errstr, 60, STREAM_CLIENT_CONNECT);
        }
        if (!$this->socket ) {
            if($this->debug) error_log("stream_socket_create() $errno, $errstr 
");
            return false;
        }
        stream_set_timeout($this->socket, 5);
        stream_set_blocking($this->socket, 0);
        $i = 0;
        $buffer = "";
        $buffer .= chr(0x00); $i++;
        $buffer .= chr(0x06); $i++;
        $buffer .= chr(0x4d); $i++;
        $buffer .= chr(0x51); $i++;
        $buffer .= chr(0x49); $i++;
        $buffer .= chr(0x73); $i++;
        $buffer .= chr(0x64); $i++;
        $buffer .= chr(0x70); $i++;
        $buffer .= chr(0x03); $i++;
        //No Will
        $var = 0;
        if($clean) $var+=2;
        //Add will info to header
        if($this->will != NULL){
            $var += 4; // Set will flag
            $var += ($this->will["qos"] << 3); //Set will qos
            if($this->will["retain"])    $var += 32; //Set will retain
        }
        if($this->username != NULL) $var += 128;    //Add username to header
        if($this->password != NULL) $var += 64;    //Add password to header
        $buffer .= chr($var); $i++;
        //Keep alive
        $buffer .= chr($this->keepalive >> 8); $i++;
        $buffer .= chr($this->keepalive & 0xff); $i++;
        $buffer .= $this->strwritestring($this->clientid,$i);
        //Adding will to payload
        if($this->will != NULL){
            $buffer .= $this->strwritestring($this->will["topic"],$i);
            $buffer .= $this->strwritestring($this->will["content"],$i);
        }
        if($this->username) $buffer .= $this->strwritestring($this->username,$i);
        if($this->password) $buffer .= $this->strwritestring($this->password,$i);
        $head = "  ";
        $head{0} = chr(0x10);
        $head{1} = chr($i);
        fwrite($this->socket, $head, 2);
        fwrite($this->socket,  $buffer);
        $string = $this->read(4);
        if(ord($string{0})>>4 == 2 && $string{3} == chr(0)){
            if($this->debug) echo "Connected to Broker
";
        }else{
            error_log(sprintf("Connection failed! (Error: 0x%02x 0x%02x)
",
                ord($string{0}),ord($string{3})));
            return false;
        }
        $this->timesinceping = time();
        return true;
    }
    /* read: reads in so many bytes */
    function read($int = 8192, $nb = false){
        //    print_r(socket_get_status($this->socket));
        $string="";
        $togo = $int;
        if($nb){
            return fread($this->socket, $togo);
        }
        while (!feof($this->socket) && $togo>0) {
            $fread = fread($this->socket, $togo);
            $string .= $fread;
            $togo = $int - strlen($string);
        }
        return $string;
    }
    /* subscribe: subscribes to topics */
    function subscribe($topics, $qos = 0){
        $i = 0;
        $buffer = "";
        $id = $this->msgid;
        $buffer .= chr($id >> 8);  $i++;
        $buffer .= chr($id % 256);  $i++;
        foreach($topics as $key => $topic){
            $buffer .= $this->strwritestring($key,$i);
            $buffer .= chr($topic["qos"]);  $i++;
            $this->topics[$key] = $topic;
        }
        $cmd = 0x80;
        //$qos
        $cmd +=    ($qos << 1);
        $head = chr($cmd);
        $head .= chr($i);
        fwrite($this->socket, $head, 2);
        fwrite($this->socket, $buffer, $i);
        $string = $this->read(2);
        $bytes = ord(substr($string,1,1));
        $string = $this->read($bytes);
    }
    /* ping: sends a keep alive ping */
    function ping(){
        $head = " ";
        $head = chr(0xc0);
        $head .= chr(0x00);
        fwrite($this->socket, $head, 2);
        if($this->debug) echo "ping sent
";
    }
    /* disconnect: sends a proper disconect cmd */
    function disconnect(){
        $head = " ";
        $head{0} = chr(0xe0);
        $head{1} = chr(0x00);
        fwrite($this->socket, $head, 2);
    }
    /* close: sends a proper disconect, then closes the socket */
    function close(){
        $this->disconnect();
        stream_socket_shutdown($this->socket, STREAM_SHUT_WR);
    }
    /* publish: publishes $content on a $topic */
    function publish($topic, $content, $qos = 0, $retain = 0){
        $i = 0;
        $buffer = "";
        $buffer .= $this->strwritestring($topic,$i);
        //$buffer .= $this->strwritestring($content,$i);
        if($qos){
            $id = $this->msgid++;
            $buffer .= chr($id >> 8);  $i++;
            $buffer .= chr($id % 256);  $i++;
        }
        $buffer .= $content;
        $i+=strlen($content);
        $head = " ";
        $cmd = 0x30;
        if($qos) $cmd += $qos << 1;
        if($retain) $cmd += 1;
        $head{0} = chr($cmd);
        $head .= $this->setmsglength($i);
        fwrite($this->socket, $head, strlen($head));
        fwrite($this->socket, $buffer, $i);
    }
    /* message: processes a recieved topic */
    function message($msg){
        $tlen = (ord($msg{0})<<8) + ord($msg{1});
        $topic = substr($msg,2,$tlen);
        $msg = substr($msg,($tlen+2));
        $found = 0;
        foreach($this->topics as $key=>$top){
            if( preg_match("/^".str_replace("#",".*",
                    str_replace("+","[^/]*",
                        str_replace("/","/",
                            str_replace("$","$",
                                $key))))."$/",$topic) ){
                if(is_callable($top["function"])){
                    call_user_func($top["function"],$topic,$msg);
                    $found = 1;
                }
            }
        }
        if($this->debug && !$found) echo "msg recieved but no match in subscriptions
";
    }
    /* proc: the processing loop for an "allways on" client
        set true when you are doing other stuff in the loop good for watching something else at the same time */
    function proc( $loop = true){
        if(1){
            $sockets = array($this->socket);
            $w = $e = NULL;
            $cmd = 0;
            //$byte = fgetc($this->socket);
            if(feof($this->socket)){
                if($this->debug) echo "eof receive going to reconnect for good measure
";
                fclose($this->socket);
                $this->connect_auto(false);
                if(count($this->topics))
                    $this->subscribe($this->topics);
            }
            $byte = $this->read(1, true);
            if(!strlen($byte)){
                if($loop){
                    usleep(100000);
                }
            }else{
                $cmd = (int)(ord($byte)/16);
                if($this->debug) echo "Recevid: $cmd
";
                $multiplier = 1;
                $value = 0;
                do{
                    $digit = ord($this->read(1));
                    $value += ($digit & 127) * $multiplier;
                    $multiplier *= 128;
                }while (($digit & 128) != 0);
                if($this->debug) echo "Fetching: $value
";
                if($value)
                    $string = $this->read($value);
                if($cmd){
                    switch($cmd){
                        case 3:
                            $this->message($string);
                            break;
                    }
                    $this->timesinceping = time();
                }
            }
            if($this->timesinceping < (time() - $this->keepalive )){
                if($this->debug) echo "not found something so ping
";
                $this->ping();
            }
            if($this->timesinceping<(time()-($this->keepalive*2))){
                if($this->debug) echo "not seen a package in a while, disconnecting
";
                fclose($this->socket);
                $this->connect_auto(false);
                if(count($this->topics))
                    $this->subscribe($this->topics);
            }
        }
        return 1;
    }
    /* getmsglength: */
    function getmsglength(&$msg, &$i){
        $multiplier = 1;
        $value = 0 ;
        do{
            $digit = ord($msg{$i});
            $value += ($digit & 127) * $multiplier;
            $multiplier *= 128;
            $i++;
        }while (($digit & 128) != 0);
        return $value;
    }
    /* setmsglength: */
    function setmsglength($len){
        $string = "";
        do{
            $digit = $len % 128;
            $len = $len >> 7;
            // if there are more digits to encode, set the top bit of this digit
            if ( $len > 0 )
                $digit = ($digit | 0x80);
            $string .= chr($digit);
        }while ( $len > 0 );
        return $string;
    }
    /* strwritestring: writes a string to a buffer */
    function strwritestring($str, &$i){
        $ret = " ";
        $len = strlen($str);
        $msb = $len >> 8;
        $lsb = $len % 256;
        $ret = chr($msb);
        $ret .= chr($lsb);
        $ret .= $str;
        $i += ($len+2);
        return $ret;
    }
    function printstr($string){
        $strlen = strlen($string);
        for($j=0;$j<$strlen;$j++){
            $num = ord($string{$j});
            if($num > 31)
                $chr = $string{$j}; else $chr = " ";
            printf("%4d: %08b : 0x%02x : %s 
",$j,$num,$num,$chr);
        }
    }
}

</>复制代码 
 // 发送给订阅号信息,创建socket,无sam队列
 $server = "127.0.0.1";     // 服务代理地址(mqtt服务端地址)
 $port = 1883;                     // 通信端口
 $username = "";                   // 用户名(如果需要)
 $password = "";                   // 密码(如果需要
 $client_id = "clientx9293670xxctr"; // 设置你的连接客户端id
 $mqtt = new Mqtt($server, $port, $client_id); //实例化MQTT类
 if ($mqtt->connect(true, NULL, $username, $password)) { 
    //如果创建链接成功
     $mqtt->publish("xxx3809293670ctr", "setr=3xxxxxxxxx", 0); 
     // 发送到 xxx3809293670ctr 的主题 一个信息 内容为 setr=3xxxxxxxxx Qos 为 0 
     $mqtt->close();    //发送后关闭链接
 } else {
     echo "Time out!
"; 
 }

</>复制代码 
/*// 订阅信息,接收一个信息后退出
$server = "127.0.0.1";     // 服务代理地址(mqtt服务端地址)
$port = 1883;                     // 通信端口
$username = "";                   // 用户名(如果需要)
$password = "";                   // 密码(如果需要
$client_id = "clientx9293670xxctr"; // 设置你的连接客户端id
$mqtt = new Mqtt($server, $port, $client_id);
if(!$mqtt->connect(true, NULL, $username, $password)) { //链接不成功再重复执行监听连接
    exit(1);
}
$topics["SN69143809293670state"] = array("qos" => 0, "function" => "procmsg");
// 订阅主题为 SN69143809293670state qos为0
$mqtt->subscribe($topics, 0);
while($mqtt->proc()){
}
//死循环监听
$mqtt->close();
function procmsg($topic, $msg){ //信息回调函数 打印信息
        echo "Msg Recieved: " . date("r") . "
";
        echo "Topic: {$topic}
";
        echo "
$msg
";
        $xxx = json_decode($msg);
        var_dump($xxxxxx->aa);
        die;
}

这是php实现方法,如果用php做发送端还是不错的.但是

我被这个图片打击了,区块链应用还真提莫的是js写起来跟简单;

我最终写出的mqtt api 使用的是node;为什么?

node.js实现mqtt