Source code:

int rolePin = 2; // pin that connects the relay 
int magnetPin = 3; // pin that connects magnetic switches 
int wait = 10000; // time to turn off light (in milliseconds) 
boolean doorStatus = false;


void setup() { 
pinMode(rolePin, OUTPUT); 
pinMode(magnetPin, INPUT_PULLUP); 


} 


void loop() { 
int magnetState = digitalRead(magnetPin); 


if (magnetState == HIGH) { 
digitalWrite(rolePin, HIGH);  
doorStatus = true;
} 
else{ 
  if (doorStatus == true) {
delay(wait);
digitalWrite(rolePin, LOW); 
doorStatus = false;
 }
} 
delay(5);
}