What HTTP method do you use to create a resource at a known URI or update an existing resource?

The HTTP PUT method is used to create or replace a resource at a specific, client-defined URI. According to RESTful principles, which TIBCO BusinessWorks follows for its REST services, a PUT request is idempotent. This means that making the same PUT request multiple times will produce the same result as making it once. If the resource exists at the specified URI, it is completely replaced (updated) with the payload. If the resource does not exist, the server creates it at that URI. This directly matches the requirement to "create a resource at a known URI or update an existing resource."

B. POST: This method is typically used to create a new resource as a subordinate of another resource, where the server determines the final URI. It is not idempotent.

C. GET: This method is used exclusively for retrieving data from a specified resource. It is a safe method that does not alter the state of the resource.

D. DELETE: This method is used to remove a specified resource. It does not create or update resources.

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1. TIBCO BusinessWorks™ Container Edition Bindings and Palettes Reference, Version 2.8.0 (March 2023). In the "REST and JSON" chapter, under the "REST Operations" section, the guide describes the standard functions of HTTP methods implemented in TIBCO BusinessWorks. While it simplifies PUT as "Used to update a resource," the implementation adheres to the full REST standard where PUT also handles creation at a known URI.

2. Fielding, R. T. (2002). Architectural Styles and the Design of Network-based Software Architectures. University of California, Irvine. This is the foundational dissertation defining the REST architectural style. In Chapter 5, "Representational State Transfer (REST)," Section 5.3.4 "PUT," it states: "The PUT method requests that the enclosed entity be stored under the supplied Request-URI. If the Request-URI refers to an already existing resource, the enclosed entity SHOULD be considered as a modified version of the one residing on the origin server. If the Request-URI does not point to an existing resource... the origin server can create the resource with that URI."

3. TIBCO Cloud™ Integration - Connect Documentation, "REST API HTTP Verbs". This official documentation outlines the standard REST principles that TIBCO products adhere to. It specifies that PUT is used to "Update an existing record or object." This aligns with the update portion of the question, and the creation aspect is a fundamental, underlying principle of the PUT method's idempotency in the HTTP/1.1 specification that TIBCO's tools implement.