rest - How is the blanket recommendation to version RESTful APIs justified for web-only apps? -

the blanket recommendation restful api should accessed through version number (/api/v1, /api/v2, ..) puzzling.

if restful api accessed mobile app or desktop program, it's evident versioning necessary. older apps/programs installed on users' devices should continue function when breaking change introduced api.

but suppose app purely web app. html5 served match current api version. there reason version api, besides potential future implementation of mobile apps or desktop programs targeting same api?

it not @ blanket recommendation. in fact, lots of folks argue it's bad practice. many best practices, there's people in either camp.

if control caller , callee, think can take lot more liberty in terms of best practices can ignore. keep in mind though, things, after being built, might take life on own used in unexpected contexts. can lot more expensive rebuild new use-case, rather build scratch.

especially if relatively easy (planning versioning might one), think in camp of doing things possible , ignore best practices in cases there's strong business case so. saving lot of time one.