PHP边缘计算与物联网数据采集物联网场景中边缘设备需要采集传感器数据并进行初步处理。PHP可以运行在边缘设备上MQTT协议是物联网通信的标准协议。今天说说PHP在物联网数据采集中的应用。PHP通过MQTT协议与物联网设备通信。可以使用php-mqtt库或直接通过socket连接MQTT代理。phpclass MqttClient{private $socket;private string $host;private int $port;private string $clientId;private array $callbacks [];public function __construct(string $host localhost, int $port 1883, string $clientId ){$this-host $host;$this-port $port;$this-clientId $clientId ?: php_client_ . bin2hex(random_bytes(4));}public function connect(): bool{$this-socket fsockopen($this-host, $this-port, $errno, $errstr, 5);if (!$this-socket) {throw new \RuntimeException(连接失败: {$errstr});}// MQTT CONNECT报文$variableHeader pack(n, strlen($this-clientId)) . $this-clientId;$fixedHeader chr(0x10);$remainingLength strlen($variableHeader);$fixedHeader . chr($remainingLength);fwrite($this-socket, $fixedHeader . $variableHeader);$response fread($this-socket, 4);if (strlen($response) 4) return false;return true;}public function subscribe(string $topic, callable $callback): void{$this-callbacks[$topic] $callback;// MQTT SUBSCRIBE报文$packetId 1;$topicLength strlen($topic);$payload pack(n, $packetId) . pack(n, $topicLength) . $topic . chr(0);$fixedHeader chr(0x82);$remainingLength strlen($payload);$fixedHeader . chr($remainingLength);fwrite($this-socket, $fixedHeader . $payload);}public function publish(string $topic, string $message): void{$topicLength strlen($topic);$payload pack(n, $topicLength) . $topic . $message;$fixedHeader chr(0x30);$remainingLength strlen($payload);$fixedHeader . chr($remainingLength);fwrite($this-socket, $fixedHeader . $payload);}public function loop(): void{while (!feof($this-socket)) {$byte fread($this-socket, 1);if ($byte false || $byte ) break;$type ord($byte) 4;if ($type 3) { // PUBLISH$remaining ord(fread($this-socket, 1));$topicLength unpack(n, fread($this-socket, 2))[1];$topic fread($this-socket, $topicLength);$message fread($this-socket, $remaining - 2 - $topicLength);if (isset($this-callbacks[$topic])) {($this-callbacks[$topic])($topic, $message);}}}}public function disconnect(): void{if ($this-socket) {fwrite($this-socket, chr(0xE0) . chr(0x00));fclose($this-socket);}}}// MQTT示例$client new MqttClient(mqtt.eclipseprojects.io, 1883);try {$client-connect();$client-subscribe(sensors/temperature, function ($topic, $message) {echo 收到数据 - {$topic}: {$message}\n;});// 模拟传感器数据发布for ($i 0; $i 5; $i) {$temperature 20 rand(0, 100) / 10;$humidity 50 rand(0, 100) / 10;$client-publish(sensors/temperature, json_encode([value $temperature,unit celsius,time time(),]));$client-publish(sensors/humidity, json_encode([value $humidity,unit percent,time time(),]));sleep(1);}$client-disconnect();} catch (\Exception $e) {echo 错误: {$e-getMessage()}\n;}?传感器数据采集和存储phpclass SensorDataCollector{private PDO $pdo;private array $buffer [];private int $batchSize 10;public function __construct(PDO $pdo){$this-pdo $pdo;$this-initTable();}private function initTable(): void{$this-pdo-exec(CREATE TABLE IF NOT EXISTS sensor_data (id BIGINT AUTO_INCREMENT PRIMARY KEY,device_id VARCHAR(50) NOT NULL,sensor_type VARCHAR(50) NOT NULL,value DECIMAL(10, 2) NOT NULL,unit VARCHAR(20),recorded_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,INDEX idx_device_time (device_id, recorded_at),INDEX idx_type_time (sensor_type, recorded_at)) ENGINEInnoDB DEFAULT CHARSETutf8mb4);}public function record(string $deviceId, string $type, float $value, string $unit ): void{$this-buffer[] compact(deviceId, type, value, unit);if (count($this-buffer) $this-batchSize) {$this-flush();}}public function flush(): void{if (empty($this-buffer)) return;$this-pdo-beginTransaction();$stmt $this-pdo-prepare(INSERT INTO sensor_data (device_id, sensor_type, value, unit, recorded_at)VALUES (?, ?, ?, ?, NOW()));foreach ($this-buffer as $data) {$stmt-execute([$data[deviceId], $data[type], $data[value], $data[unit]]);}$this-pdo-commit();$this-buffer [];}public function queryHistory(string $deviceId, string $type, int $minutes 60): array{$stmt $this-pdo-prepare(SELECT * FROM sensor_dataWHERE device_id ? AND sensor_type ?AND recorded_at DATE_SUB(NOW(), INTERVAL ? MINUTE)ORDER BY recorded_at ASC);$stmt-execute([$deviceId, $type, $minutes]);return $stmt-fetchAll();}public function getLatest(string $deviceId): array{$stmt $this-pdo-prepare(SELECT sensor_type, value, unit, recorded_atFROM sensor_dataWHERE device_id ?ORDER BY recorded_at DESCLIMIT 10);$stmt-execute([$deviceId]);return $stmt-fetchAll();}public function getStats(string $deviceId, string $type, int $hours 24): array{$stmt $this-pdo-prepare(SELECTMIN(value) as min_value,MAX(value) as max_value,AVG(value) as avg_value,COUNT(*) as sample_countFROM sensor_dataWHERE device_id ? AND sensor_type ?AND recorded_at DATE_SUB(NOW(), INTERVAL ? HOUR));$stmt-execute([$deviceId, $type, $hours]);return $stmt-fetch(PDO::FETCH_ASSOC);}public function __destruct(){$this-flush();}}$pdo new PDO(mysql:hostlocalhost;dbnameiot, root, );$collector new SensorDataCollector($pdo);$collector-record(device_001, temperature, 23.5, celsius);$collector-record(device_001, humidity, 65.2, percent);$collector-record(device_001, temperature, 23.8, celsius);$stats $collector-getStats(device_001, temperature, 24);echo 温度统计: . json_encode($stats, JSON_UNESCAPED_UNICODE) . \n;?PHP在物联网场景中的优势是部署简单、开发快速。通过MQTT协议采集传感器数据存入时序数据库可以构建简单的物联网数据采集系统。对于大规模的物联网平台建议使用专门的物联网平台或时序数据库来实现。
PHP边缘计算与物联网数据采集
PHP边缘计算与物联网数据采集物联网场景中边缘设备需要采集传感器数据并进行初步处理。PHP可以运行在边缘设备上MQTT协议是物联网通信的标准协议。今天说说PHP在物联网数据采集中的应用。PHP通过MQTT协议与物联网设备通信。可以使用php-mqtt库或直接通过socket连接MQTT代理。phpclass MqttClient{private $socket;private string $host;private int $port;private string $clientId;private array $callbacks [];public function __construct(string $host localhost, int $port 1883, string $clientId ){$this-host $host;$this-port $port;$this-clientId $clientId ?: php_client_ . bin2hex(random_bytes(4));}public function connect(): bool{$this-socket fsockopen($this-host, $this-port, $errno, $errstr, 5);if (!$this-socket) {throw new \RuntimeException(连接失败: {$errstr});}// MQTT CONNECT报文$variableHeader pack(n, strlen($this-clientId)) . $this-clientId;$fixedHeader chr(0x10);$remainingLength strlen($variableHeader);$fixedHeader . chr($remainingLength);fwrite($this-socket, $fixedHeader . $variableHeader);$response fread($this-socket, 4);if (strlen($response) 4) return false;return true;}public function subscribe(string $topic, callable $callback): void{$this-callbacks[$topic] $callback;// MQTT SUBSCRIBE报文$packetId 1;$topicLength strlen($topic);$payload pack(n, $packetId) . pack(n, $topicLength) . $topic . chr(0);$fixedHeader chr(0x82);$remainingLength strlen($payload);$fixedHeader . chr($remainingLength);fwrite($this-socket, $fixedHeader . $payload);}public function publish(string $topic, string $message): void{$topicLength strlen($topic);$payload pack(n, $topicLength) . $topic . $message;$fixedHeader chr(0x30);$remainingLength strlen($payload);$fixedHeader . chr($remainingLength);fwrite($this-socket, $fixedHeader . $payload);}public function loop(): void{while (!feof($this-socket)) {$byte fread($this-socket, 1);if ($byte false || $byte ) break;$type ord($byte) 4;if ($type 3) { // PUBLISH$remaining ord(fread($this-socket, 1));$topicLength unpack(n, fread($this-socket, 2))[1];$topic fread($this-socket, $topicLength);$message fread($this-socket, $remaining - 2 - $topicLength);if (isset($this-callbacks[$topic])) {($this-callbacks[$topic])($topic, $message);}}}}public function disconnect(): void{if ($this-socket) {fwrite($this-socket, chr(0xE0) . chr(0x00));fclose($this-socket);}}}// MQTT示例$client new MqttClient(mqtt.eclipseprojects.io, 1883);try {$client-connect();$client-subscribe(sensors/temperature, function ($topic, $message) {echo 收到数据 - {$topic}: {$message}\n;});// 模拟传感器数据发布for ($i 0; $i 5; $i) {$temperature 20 rand(0, 100) / 10;$humidity 50 rand(0, 100) / 10;$client-publish(sensors/temperature, json_encode([value $temperature,unit celsius,time time(),]));$client-publish(sensors/humidity, json_encode([value $humidity,unit percent,time time(),]));sleep(1);}$client-disconnect();} catch (\Exception $e) {echo 错误: {$e-getMessage()}\n;}?传感器数据采集和存储phpclass SensorDataCollector{private PDO $pdo;private array $buffer [];private int $batchSize 10;public function __construct(PDO $pdo){$this-pdo $pdo;$this-initTable();}private function initTable(): void{$this-pdo-exec(CREATE TABLE IF NOT EXISTS sensor_data (id BIGINT AUTO_INCREMENT PRIMARY KEY,device_id VARCHAR(50) NOT NULL,sensor_type VARCHAR(50) NOT NULL,value DECIMAL(10, 2) NOT NULL,unit VARCHAR(20),recorded_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,INDEX idx_device_time (device_id, recorded_at),INDEX idx_type_time (sensor_type, recorded_at)) ENGINEInnoDB DEFAULT CHARSETutf8mb4);}public function record(string $deviceId, string $type, float $value, string $unit ): void{$this-buffer[] compact(deviceId, type, value, unit);if (count($this-buffer) $this-batchSize) {$this-flush();}}public function flush(): void{if (empty($this-buffer)) return;$this-pdo-beginTransaction();$stmt $this-pdo-prepare(INSERT INTO sensor_data (device_id, sensor_type, value, unit, recorded_at)VALUES (?, ?, ?, ?, NOW()));foreach ($this-buffer as $data) {$stmt-execute([$data[deviceId], $data[type], $data[value], $data[unit]]);}$this-pdo-commit();$this-buffer [];}public function queryHistory(string $deviceId, string $type, int $minutes 60): array{$stmt $this-pdo-prepare(SELECT * FROM sensor_dataWHERE device_id ? AND sensor_type ?AND recorded_at DATE_SUB(NOW(), INTERVAL ? MINUTE)ORDER BY recorded_at ASC);$stmt-execute([$deviceId, $type, $minutes]);return $stmt-fetchAll();}public function getLatest(string $deviceId): array{$stmt $this-pdo-prepare(SELECT sensor_type, value, unit, recorded_atFROM sensor_dataWHERE device_id ?ORDER BY recorded_at DESCLIMIT 10);$stmt-execute([$deviceId]);return $stmt-fetchAll();}public function getStats(string $deviceId, string $type, int $hours 24): array{$stmt $this-pdo-prepare(SELECTMIN(value) as min_value,MAX(value) as max_value,AVG(value) as avg_value,COUNT(*) as sample_countFROM sensor_dataWHERE device_id ? AND sensor_type ?AND recorded_at DATE_SUB(NOW(), INTERVAL ? HOUR));$stmt-execute([$deviceId, $type, $hours]);return $stmt-fetch(PDO::FETCH_ASSOC);}public function __destruct(){$this-flush();}}$pdo new PDO(mysql:hostlocalhost;dbnameiot, root, );$collector new SensorDataCollector($pdo);$collector-record(device_001, temperature, 23.5, celsius);$collector-record(device_001, humidity, 65.2, percent);$collector-record(device_001, temperature, 23.8, celsius);$stats $collector-getStats(device_001, temperature, 24);echo 温度统计: . json_encode($stats, JSON_UNESCAPED_UNICODE) . \n;?PHP在物联网场景中的优势是部署简单、开发快速。通过MQTT协议采集传感器数据存入时序数据库可以构建简单的物联网数据采集系统。对于大规模的物联网平台建议使用专门的物联网平台或时序数据库来实现。
