philologist's techblog

Let’s skip playing an annoying greeting for the caller, if he already called us withing the last 10 minutes.

Create a macro:

macro greetBlock( ext )
{
    if(${DB_EXISTS(greetblock/${CALLERID(num)})}) {
        // get the last call's timestamp.
        Set(LASTCALL=${DB(greetblock/${CALLERID(num)})});
    } else {
        Set(LASTCALL=0);
    }

    Set(NOW=${EPOCH});
    Set(DIFF=${MATH(${NOW} - ${LASTCALL},int)});

    if ("${LASTCALL}" != "" & ${DIFF} < 600) {
        // a person called less than 10 minutes ago - skip greeting.
        NoOp(skip greeting to ${CALLERID(num)} for ${ext});
        Set(GREETING=0);
    } else {
        Set(DB(greetblock/${CALLERID(num)})=${NOW});
        Set(GREETING=1);
    }

    return;
};

And use this macro in your dialplan:

73333123456 =>
{
  NoOp(${STRFTIME(,,%F %R)} . ${CALLERID(num)} dials SALES office . callid start: ${SIP_HEADER(Call-ID)});

  &greetBlock(${EXTEN});
    
  if ("${GREETING}" = "1") {
    goto greeton;
  } else {
    goto greetoff;
  }

  greeton:
    Playback(${SOUNDS}/welcome);

  greetoff:
    Queue(...);
    ...
}