tocar (a) la puerta vs golpear la puerta

Question

I heard the following sentence in the Narcos TV series (which takes place in Colombia):

Espere un momento, que me están tocando la puerta.

1) Isn't the idiomatic expression "tocar a la puerta" ?

2) Is there any difference in meaning between "tocar a la puerta" and "golpear la puerta" ? Could I use the latter in the above sentence?

Answer 1

"Tocar a la puerta" is "to knock at the door".

He aquí, yo estoy a la puerta y llamo; si alguno oye mi voz y abre la puerta, entraré a él... -Apocalipsis 3.20 RVR1960

I stand at the door and knock... -same, KJV

"Tocar la puerta" is "to knock on the door" or simply "to touch the door"

"Golpear la puerta" sounds more forceful, like "to strike the door", or in the case of "golpear a la puerta", "to strike at the door".

Answer 2

1. It is incorrect to say "a la puerta". In Spanish you only add "a" to the direct object when it is a person, not an object. For example, we say "He visto a Maria" but never "He visto Maria". Actually if you say "tocar a la puerta" I would feel like they are actually touching it, not knocking it.
2. Both "Tocar" and "Golpear" mean the same in this context, I don't see any difference. In the northwest part of Spain they even use another verb, "Petar".