Example code for NodeMCU to connect with server side by using Socket.io and Arduino IDE

In this case, I'm using washo4evr's librady.
Please refer to https://github.com/washo4evr/Socket.io-v1.x-Library

Create folder name ~\SocketIOClient and download SocketIOClient.cpp and SocketIOClient.h to your library directory of Arduino.
Ex. C:\Program Files (x86)\Arduino\libraries\SocketIOClient\


/* [NEED] --- Include something need, example WiFi library, Arduino --- */

#include <SocketIOClient.h>

/* [NEED] --- Declare something need, example WiFi library --- */

SocketIOClient client;

StaticJsonBuffer<200> jsonBuffer;
JsonObject& root = jsonBuffer.createObject();

extern String RID;
extern String Rname;
extern String Rcontent;

char hostip[] = "YOUR_HOST_IP";
int port = YOUR_PORT_NUMBER;

void setup();
void loop();

void setup() {

  /* [NEED] --- Initial anything that you want --- */

  /* [NEED] --- Try to connect to WiFi --- */

  if (!client.connect(hostip, port)) {
    Serial.println("connection failed");
  }
  if (client.connected()){
    client.send("connection", "message", );
  }
}

void loop() {
  if(client.monitor()){

    // Ex. Sending side(package from server)
    //     socket.emit("EVENT_NAME", { "ATTRIBUTE_OF_OBJ" : SOMETHING });

    if(RID == "EVENT_NAME"){
      if(Rname == "ATTRIBUTE_OF_OBJ"){ 
        Serial.print("Got " + Rcontent);
        // Output : Got SOMETHING
      }
    }
  }
}