To start with: unplug from the computer!
The soda you are talking about, is this with sugar or not?
Then take the keyboard to the kitchen sink.
Now, if the the soda only contains water, let be there for at least 24, perhaps even 36 hours to let it dry.
If it contains sugar, or hobs and malt like a beer or coffee, well then it's more problematic.
You really had to loosen up the back panel, release all the buttons, and then do not use water, instead go to the local store and get some Isopropanol. That is an alcohol which will not damage the electronics at all.
Then soek it in, use the Isopropanol and a lint-free cloth to clean up every thing, especially the electrical contacts.
Then let it dry in room temperature for at least 24 to 36 hours.
Best regards from Sweden