Depends on how you are serializing the messages. In other words, the best way to phrase this (/ search for an existing answer) is to identify how you are serializing the messages and then find out how that mechanism deals with the issue.
Assuming it's JSON with JSON.NET and simple POCOs, then the answer is that adding a property is handled pretty cleanly - in the absence of any customizations (which is very doable), new fields come in withe default(T)
, i.e. null
or 0
for each relevant value.