longer interval/specific date for scheduler

[coelner]

I can't find any directly related issue.

I need to activate a switch by a longer period than on daily base. Once in a month I want to start a system. Sometimes I would need a specific date and not an interval.

[mcspr]

As I am not really in favour of adding yet another kv pair to the scheduler engine... I guess we can extend RPN rules instead? See this example:
https://github.com/xoseperez/espurna/wiki/RPN-Rules#open-light-at-night-if-there-is-presence

It matches the existing functionality of scheduler to compare hour, minute and day of week. e.g., here's the piece of code to return weekday match:

espurna/code/espurna/rpnrules.ino

Lines 134 to 140 in 37763f1

	rpn_operator_set(_rpn_ctxt, "dow", 1, [](rpn_context & ctxt) {
	float a;
	rpn_stack_pop(ctxt, a);
	unsigned char dow = (weekday(int(a)) + 5) % 7;
	rpn_stack_push(ctxt, dow);
	return true;
	});

We can add an additional operator day / dom / or longer dayofmonth to match the month day instead

[mcspr]

Part of the scheduler update, YYYY-MM-DD can be specified in addition to DOW and HH:MM
https://github.com/xoseperez/espurna/wiki/Scheduler#time-string