An HTTP response for 204 No Content indicates success, but that nothing will be sent back in body. I was interested to find in my latest job that we were using 204 on DELETE endpoints and on update a few places, which seemed like a novel idea.
However, after thinking about it longer, I wouldn’t endorse using 204s for two reasons:
Say you have an endpoint that doesn’t need to return anything for now, but then later on you realize that it’d be useful if it did. A 204 has boxed you in: it’s against the spec to return a body with one, and languages like Go will error if you try. You could change the status code, but that should be considered to be a minor breaking change because so many integrations are written like if resp.StatusCode != http.StatusNoContent { <error> }.
Instead, just return a 200 with an empty JSON object for endpoints that don’t need a response. The difference is immaterial to clients, and adding new data later is fully backwards compatible.
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