// These properties are guarded by [lock].

  /**
   * If true, no new exchanges can be created on this connection. It is necessary to set this to
   * true when removing a connection from the pool; otherwise a racing caller might get it from the
   * pool when it shouldn't. Symmetrically, this must always be checked before returning a
   * connection from the pool.
   *
   * Once true this is always true. Guarded by this.
   */

 * the HTTP message.
 *
 * This class tracks header values line-by-line. A field with multiple comma- separated values on
 * the same line will be treated as a field with a single value by this class. It is the caller's
 * responsibility to detect and split on commas if their field permits multiple values. This
 * simplifies use of single-valued fields whose values routinely contain commas, such as cookies or
 * dates.
 *

```

Le mot-clé important ici est `await`. Il informe Python qu'il faut attendre ⏸ que `get_burgers(2)` finisse d'effectuer ses opérations 🕙 avant de stocker les résultats dans la variable `burgers`. Grâce à cela, Python saura qu'il peut aller effectuer d'autres opérations 🔀 ⏯ pendant ce temps (comme par exemple recevoir une autre requête).

 *
 * Implementations authenticate by returning a follow-up request that includes an authorization
 * header, or they may decline the challenge by returning null. In this case the unauthenticated
 * response will be returned to the caller that triggered it.
 *
 * Implementations should check if the initial request already included an attempt to
 * authenticate. If so it is likely that further attempts will not be useful and the authenticator
 * should give up.

   * auth param in the challenge at key null. Invalid headers and challenges are ignored.
   * No semantic validation is done, for example that `Basic` auth must have a `realm`
   * auth param, this is up to the caller that interprets these challenges.
   */
  fun challenges(): List<Challenge> {
    return headers.parseChallenges(
      when (code) {
        HTTP_UNAUTHORIZED -> "WWW-Authenticate"

MinIO root or IAM credentials. Therefore, you can distribute an application (for example, on mobile devices) that requests temporary security credentials without including MinIO long lasting credentials in the application. Instead, the identity of the caller is validated by using a JWT id_token from the web identity provider. The temporary security credentials returned by this API consists of an access key, a secret key, and a security token. Applications can use these temporary security credentials to...

You can use the same dependency overrides from [Testing Dependencies with Overrides](testing-dependencies.md){.internal-link target=_blank} to alter a database for testing.

You could want to set up a different database for testing, rollback the data after the tests, pre-fill it with some testing data, etc.

The main idea is exactly the same you saw in that previous chapter.

   * hosting filesystem becomes unreachable, the iterator will omit elements rather than throwing
   * exceptions.
   *
   * **The caller must [close][Snapshot.close]** each snapshot returned by [Iterator.next]. Failing
   * to do so leaks open files!
   */
  @Synchronized
  @Throws(IOException::class)
  fun snapshots(): MutableIterator<Snapshot> {

```

</details>

## Was ist ein Container?

Container (hauptsächlich Linux-Container) sind eine sehr **leichtgewichtige** Möglichkeit, Anwendungen einschließlich aller ihrer Abhängigkeiten und erforderlichen Dateien zu verpacken und sie gleichzeitig von anderen Containern (anderen Anwendungen oder Komponenten) im selben System isoliert zu halten.

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

## Documentation de l'API alternative