BelkinWemoPlugToggle.ino

/*
 *  Belkin Wemo Plug Toggle, tested on an ESP-01S
 *  
    This Arduino sketch checks the status of a Belkin Wemo Plug.
    If the switch is off, it makes a second request to turn it on. If the 
    switch is on,  it makes a second request to turn it off. It's highly 
    recommended you give the Wemo Switch and the device running this code
    static IPs on your network.
*/

#include <ESP8266WiFi.h>
#include <ESP8266HTTPClient.h>

// WiFi Information
const char* ssid     = "NETWORK_NAME";
const char* password = "NETWORK_PASSWORD";

// Wemo Switch IP Address, you can get this from your router
// Or this project can help: https://github.com/iancmcc/ouimeaux
const char* ipAddress = "192.168.1.111";

// Static IP Address/Network Info of your Arduino Device
IPAddress local_IP(192, 168, 1, 222);
IPAddress gateway(192, 168, 1, 1);
IPAddress subnet(255, 255, 0, 0);
IPAddress primaryDNS(8, 8, 8, 8);
IPAddress secondaryDNS(8, 8, 4, 4);

void setup() {
  Serial.begin(115200);

  // Connect to WiFi
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  // Explicitly set the ESP8266 to be a WiFi-client, not a server
  WiFi.mode(WIFI_STA);

  // Configure static IP address
  if (!WiFi.config(local_IP, gateway, subnet, primaryDNS, secondaryDNS)) {
    Serial.println("STA Failed to configure");
  }

  // Start WiFi Connection
  WiFi.begin(ssid, password);

  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("WiFi connected with IP: " );
  Serial.println(WiFi.localIP());

  WiFiClient client;
  HTTPClient http;

  String postData = "<?xml version=\"1.0\" encoding=\"utf-8\"?><s:Envelope xmlns:s=\"http://schemas.xmlsoap.org/soap/envelope/\" s:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\"><s:Body><u:GetBinaryState xmlns:u=\"urn:Belkin:service:basicevent:1\"></u:GetBinaryState></s:Body></s:Envelope>";
    
  // Start First HTTP POST to retrieve switch status (0 for off, 1 for on)
  Serial.print("[HTTP] begin...\n");
  http.begin(client, (String)"http://" + ipAddress + ":49153/upnp/control/basicevent1");
  http.addHeader("Content-Length", (String)postData.length());
  http.addHeader("Content-Type", "text/xml; charset=\"utf-8\"");
  http.addHeader("SOAPACTION", "\"urn:Belkin:service:basicevent:1#GetBinaryState\"");

  Serial.print("[HTTP] POST 1...\n");
  int httpCode = http.POST(postData);

  // If HTTP code is not negative, the POST succeeded
  if (httpCode > 0) {
    Serial.printf("[HTTP] POST 1... response code: %d\n", httpCode);
    
    if (httpCode == HTTP_CODE_OK) {
      const String& payload = http.getString();
      Serial.println("received payload:\n<<");
      Serial.println(payload);

      // Turn switch on by default
      String action = "<u:SetBinaryState xmlns:u=\"urn:Belkin:service:basicevent:1\"><BinaryState>1</BinaryState></u:SetBinaryState>";
  
      // If switch already on, turn off instead
      if( payload.indexOf("<BinaryState>1</BinaryState>") > 0) {
        action = "<u:SetBinaryState xmlns:u=\"urn:Belkin:service:basicevent:1\"><BinaryState>0</BinaryState></u:SetBinaryState>";
      }

      // Build HTTP Post Data for turning switch on (or off)
      postData.replace( "<u:GetBinaryState xmlns:u=\"urn:Belkin:service:basicevent:1\"></u:GetBinaryState>", action);
      
      // Start second HTTP Post to turn switch on (or off)
      Serial.print("[HTTP] begin...\n");
      http.begin(client, (String)"http://" + ipAddress + ":49153/upnp/control/basicevent1");
      http.addHeader("Content-Length", (String)postData.length());
      http.addHeader("Content-Type", "text/xml; charset=\"utf-8\"");
      http.addHeader("SOAPACTION", "\"urn:Belkin:service:basicevent:1#SetBinaryState\"");
     
      Serial.print("[HTTP] POST 2...\n");
      // start connection and send HTTP header and body
      int httpCode = http.POST(postData);
    
      if (httpCode > 0) {
        Serial.printf("[HTTP] POST 2... response code: %d\n", httpCode);
    
        if (httpCode == HTTP_CODE_OK) {
            const String& payload = http.getString();
            Serial.println("Received payload:\n<<");
            Serial.println(payload);
            Serial.println(">>");
        }
      }
      else {
        Serial.printf("[HTTP] POST 2... failed, error: %s\n", http.errorToString(httpCode).c_str());
      }
    }
  } 
  else {
    Serial.printf("[HTTP] POST 1... failed, error: %s\n", http.errorToString(httpCode).c_str());
  }

  // Close the connection
  http.end();
  client.stop();
  delay(3000); 

  // Go to sleep to conserve battery
  ESP.deepSleep(0);  

}

void loop() {}