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  • Dan Sanders thinks this is interesting:

The GET, PUT, and DELETE methods are said to be idempotent; that is, calling them over and over will produce the same result without any additional side effects. For example, the caller should be able to call the DELETE action on a specific resource without receiving any errors and without harming the system. If the resource has already been deleted, the caller should not receive an error. The same applies to the PUT action. For a given unique resource (identified by an element URI), submitting a PUT request should update the resource if it already exists. Or, if it doesn’t exist, the system should create the resource as submitted. In other words, calling PUT over and over produces the same result without any...