title: Why isn't HTTP PUT allowed to do partial updates in a REST API?
body: <p>Who says RESTful APIs must support partial updates separately via HTTP PATCH?</p>
  
  <p>It seems to have no benefits. It adds more work to implement on the server side and more logic on the client side to decide which kind of update to request.</p>
  
  <p>I am asking this question within the context of creating a REST API with HTTP that provides abstraction to known data models. Requiring PATCH for partial updates as opposed to PUT for full or partial feels like it has no benefit, but I could be persuaded.</p>
  
  <p><strong>Related</strong></p>
  
  <p><a href="http://restcookbook.com/HTTP%20Methods/idempotency/" rel="noreferrer">http://restcookbook.com/HTTP%20Methods/idempotency/</a> - this implies you don't have control over the server software that may cache requests.</p>
  
  <p><a href="https://stackoverflow.com/questions/2364110/whats-the-justification-behind-disallowing-partial-put">What&#39;s the justification behind disallowing partial PUT?</a> - no clear answer given, only reference to what HTTP defines for PUt vs PATCH.</p>
  
  <p><a href="http://groups.yahoo.com/neo/groups/rest-discuss/conversations/topics/17415" rel="noreferrer">http://groups.yahoo.com/neo/groups/rest-discuss/conversations/topics/17415</a> - shows the divide of thoughts on this.</p>