ESP8266 not accessing PHP file I'm trying to control NodeMCU via Android application and I can control NodeMCU easily but when I added the URL to hit the PHP code to enter data in MYSQL, neither NodeMCU is controllable nor NodeMCU is hitting the PHP code. I'm confused with content type: text/html - I'm not sure where to set this piece. Is there any mistake I'm doing or anything I'm missing?

Following is the ESP8266 code on Arduino IDE:

#include &lt;ESP8266WiFi.h&gt;

const char* ssid = "ssid";
const char* password = "password";
const char* host = "aoatech.ml";

WiFiServer server(3000);
int light1 = 13;
int light2 = 15;
int fan = 12;
int socket = 14;
String what;
int which;
String mac;

void setup() {
  Serial.begin(115200);
  delay(10);
  pinMode(light1, OUTPUT);
  pinMode(light2, OUTPUT);
  pinMode(fan, OUTPUT);
  pinMode(socket, OUTPUT);
  digitalWrite(light1, 0);
  digitalWrite(light2, 0);
  digitalWrite(fan, 0);
  digitalWrite(socket, 0);  
  Serial.print("Connecting to: ");
  Serial.print(ssid);
  WiFi.begin(ssid, password);
  Serial.println("Connecting");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected");
  server.begin();
  Serial.println("Server started");
  Serial.println(WiFi.localIP());
}

void loop() {
  WiFiClient client = server.available();
  if (!client) {
    return;
  }
  Serial.print("Connecting to ");
  Serial.println(host);
  //  const int httpPort = 3000;
  //  if (!client.connect(host, httpPort)) {
  //    Serial.println("Connection failed!");
  //    return;
  //  }
  mac = WiFi.macAddress();
  Serial.println("new client");
  while(!client.available()){
    delay(1);
  }
  String req = client.readStringUntil('\r');
  Serial.println(req);
  client.flush();
  int val;
  if (req.indexOf("/light1/1") != -1){
    val = 1;
    what = "Light_1";
    which = light1;
  }
  else if (req.indexOf("/light1/0") != -1){
    val = 0;
    what = "Light_1";
    which = light1;
  }
  else if (req.indexOf("/light2/1") != -1){
    val = 1;
    what = "Light_2"; 
    which = light2;
  }
  else if (req.indexOf("/light2/0") != -1){
    val = 0;
    what = "Light_2";
    which = light2;
  }
  else if (req.indexOf("/fan/1") != -1){
    val = 1;
    what = "Fan";
    which = fan;
  }
  else if (req.indexOf("/fan/0") != -1){
    val = 0;
    what = "Fan"; 
    which = fan;
  }
  else if (req.indexOf("/socket/1") != -1){
    val = 1;
    what = "Socket"; 
    which = socket;
  }
  else if (req.indexOf("/socket/0") != -1){
    val = 0;
    what = "Socket";
    which = socket;
  }
  else {
    Serial.println("invalid request");
    client.stop();
    return;
  }

  digitalWrite(which, val);  

  String url = "http://aoatech.ml/hitthis.php?room=Bed%20Room%201";
  url += "&amp;state=";
  url += val;
  url += "&amp;button=";
  url += what;
  url += "&amp;mac=";
  url += mac;

  Serial.print("Requesting URL: ");
  Serial.println(url);


  client.flush();
  //  client.println("HTTP/1.1 200 OK");
  //  client.println("Content-Type: text/html");
      client.print(String("GET ") + url + " HTTP/1.1\r\n" +
           "Host: " + host + "\r\n" +
           "Connection: close\r\n\r\n");
  unsigned long timeout = millis();
  while (client.available() == 0) {
    if (millis() - timeout &gt; 5000) {
      Serial.println("&gt;&gt;&gt; Client Timeout !");
      client.stop();
      return;
    }
  }  
  client.println("");
  client.print(what + " is now: ");

  if(val == 0) {
    client.print("Off");
  } else {
    client.print("On");
  }
  Serial.println("Client disonnected");
}
Your PHP server has a certain content type it can receive to process your requests from the ESP8266. The two most generic content-types used for php are either application/x-www-form-urlencoded or multipart/form-data. Try to play with those two and see if that solves it for you.