¿Cuál es un ejemplo de idempotente?

What is a example of idempotent?

In mathematics, an idempotent operation is one where f(f(x)) = f(x). For example, the abs() function is idempotent because abs(abs(x)) = abs(x) for all x .

A request method is considered “idempotent” if the intended effect on the server of multiple identical requests with that method is the same as the effect for a single such request. Of the request methods defined by this specification, PUT , DELETE , and safe request methods are idempotent.

In Functional Programming, though, an Idempotent function is one that has the property f(f(x)) = f(x) for any value x. Simply put, an operation is Idempotent if it produces the same result when called over and over.

An HTTP method is idempotent if an identical request can be made once or several times in a row with the same effect while leaving the server in the same state. Implemented correctly, the GET , HEAD , PUT , and DELETE methods are idempotent, but not the POST method. All safe methods are also idempotent.

Saying that Delete is idempotent means that if you invoque DELETE /team/1 several time the state of the system stay unchanged (in fact the first call DELETE /team/1 delete the team. In other words, delete is idempotent because duplicated call let the state of system unchanged.

Pure functions are by definition idempotent since all they do is take input values and return an output value. If the input values stay the same, so will the result.

Idempotency is important in APIs because a resource may be called multiple times if the network is interrupted. In this scenario, non-idempotent operations can cause significant unintended side-effects by creating additional resources or changing them unexpectedly.

GET, HEAD, OPTIONS and TRACE methods are defined as safe, meaning they are only intended for retrieving data. This makes them idempotent as well since multiple, identical requests will behave the same.

Idempotency means that multiple identical requests will have the same outcome. So it does not matter if a request is sent once or multiple times. The following HTTP methods are idempotent: GET, HEAD, OPTIONS, TRACE, PUT and DELETE. All safe HTTP methods are idempotent but PUT and DELETE are idempotent but not safe.

It essentially means that the result of a successfully performed request is independent of the number of times it is executed. For example, in arithmetic, adding zero to a number is idempotent operation.

An idempotent request is a request that is made with identical parameters and the outcome will always be the same, consistently (the guest is charged at most once). Guaranteeing eventual consistency for our payments system is of the utmost importance. Idempotency is a desirable mechanism to achieve this in a distributed system.

In Event stream processing, idempotence refers to the ability of a system to produce the same outcome, even if the same file, event or message is received more than once. In a load-store architecture, instructions that might possibly cause a page fault are idempotent.

An idempotent HTTP method is an HTTP method that can be called many times without different outcomes. It would not matter if the method is called only once, or ten times over. The result should be the same.