I have never seen an astronaut having a soda in space and not just in real life but also in the popular space movies.The problem with soda in space is the microgravity. The light bubbles of carbon dioxide are not able to escape to the top of the liquid in microgravity leaving quite an intense amount of gas inside the liquid. Drinking that foamy beverage full of gas could have adverse side effects. The gas will not rise above the liquid both in the container and the human stomach causing the bubbles to go through the astronaut’s digestive system. On Earth, a person can simply burp out this gas which is not possible in microgravity.
And that is not it, even if you did burp in space to release the gas, the burp will be as unpleasant as an acid reflux. It will also result in the expel of some liquid.
It has been tested back in 1985, Coca-Cola and Pepsi designed special dispensers for dispensing Coke in microgravity. According to NASA, the dispensers have not been perfected yet. So there you go no sodas for astronauts.