I did a
DC07 hose repair topic some time back, so here is the DC04 one.
I had occasion to put a DC04 hose back together earlier

As per the 07 one, the remains of the hose have been pulled out of the cuff using the finest* pliers
DO ensure the lower cord hook/clip is on the hose BEFORE you start (found that one out the hard way...)

The removal process is the same too, however you need to hold the cuff in suck a way that you can hold the cuff, screwdriver AND push the bleed valve button in

Voila

The bleed valve button pops off one side of the black ring, allowing removal for cleaning

The locking ring. I opted to leave this the

alone as it's a HATEFUL bastard if the springs pop out and do one FOREVER

The hose sits on top of the inner part, in an inferior way to the dc07, as it's not clamped externally. So, lashigns of glue, and push/twist until the end of the hose hits the stop. I then drip glue around the top join too.

Push the 2 parts back together and voila

Gonna let the glue set overnight and give it a medium pull test and see if it holds.