So we are going to use that same knowledge to document how the *external API* should look like... by creating the *path operation(s)* that the external API should implement (the ones your API will call).

/// tip

When writing the code to document a callback, it might be useful to imagine that you are that *external developer*. And that you are currently implementing the *external API*, not *your API*.

* el path `/`
* usando una <abbr title="un método HTTP GET"><code>get</code> operation</abbr>

/// info | Información sobre `@decorator`

Esa sintaxis `@algo` en Python se llama un "decorador".

Lo pones encima de una función. Como un bonito sombrero decorativo (supongo que de ahí viene el término).

Un "decorador" toma la función de abajo y hace algo con ella.

I'll tell you a bit more about these **concepts** here, and that would hopefully give you the **intuition** you would need to decide how to deploy your API in very different environments, possibly even in **future** ones that don't exist yet.

By considering these concepts, you will be able to **evaluate and design** the best way to deploy **your own APIs**.

        // spec says that we may repeat the request without modifications. Modern browsers also
        // repeat the request (even non-idempotent ones.)
        if (!client.retryOnConnectionFailure) {
          // The application layer has directed us not to retry the request.
          return null
        }

        val requestBody = userResponse.request.body

    // have this Entry. The value in the map becomes false when this first entry has been copied, so
    // we know not to copy the remaining ones.
    IdentityHashMap<Entry<K, V>, Boolean> duplicates = null;
    int dupCount = 0;
    for (int entryIndex = n - 1; entryIndex >= 0; entryIndex--) {

Para ver la diferencia, imagina la siguiente historia sobre hamburguesas:

### Hamburguesas Concurrentes

Vas con tu crush a conseguir comida rápida, te pones en fila mientras el cajero toma los pedidos de las personas frente a ti. 😍

<img src="/img/async/concurrent-burgers/concurrent-burgers-01.png" class="illustration">

        void testReadFileIdPatterns() throws Exception {
            // Test with all zeros
            byte[] zeroFileId = new byte[16];
            testFileIdReading(zeroFileId);

            // Test with all ones
            byte[] onesFileId = new byte[16];
            Arrays.fill(onesFileId, (byte) 0xFF);
            testFileIdReading(onesFileId);

            // Test with pattern

{% endif %}

{% endfor %}

</div>

## Top Translation Reviewers

These users are the **Top Translation Reviewers**. 🕵️

I only speak a few languages (and not very well 😅). So, the reviewers are the ones that have the [**power to approve translations**](contributing.md#translations){.internal-link target=_blank} of the documentation. Without them, there wouldn't be documentation in several other languages.

- [AEAD](#aead): AES-256-GCM if the CPU supports AES-NI, ChaCha20-Poly1305 otherwise. More specifically AES-256-GCM is only selected for X86-64 CPUs with AES-NI extension.

Further any secret key (apart from the KMS-generated ones) is 256 bits long. The KMS-generated keys may be 256 bits but this depends on the KMS capabilities and configuration.

        request.setPath("third\\path\\");
        assertEquals("\\third\\path", request.getPath());

        // Multiple leading backslashes - only first one gets stripped, then trailing ones get stripped
        // But getPath() adds a backslash at the beginning, so \\fourth\path\\ becomes \fourth\path\
        request.setPath("\\\\fourth\\path\\\\");
        assertEquals("\\\\fourth\\path\\", request.getPath());