# OpenAPI

There are several utilities to handle OpenAPI.

## What is "Dependency Injection" { #what-is-dependency-injection }

**"Dependency Injection"** means, in programming, that there is a way for your code (in this case, your *path operation functions*) to declare things that it requires to work and use: "dependencies".

And then, that system (in this case **FastAPI**) will take care of doing whatever is needed to provide your code with those needed dependencies ("inject" the dependencies).

			var s string
			if err = d.DecodeElement(&s, &se); err != nil {
				return err
			}
			switch se.Name.Local {
			case "Key":
				if keyAlreadyParsed {
					return errDuplicatedXMLTag
				}
				tag.Key = s
				keyAlreadyParsed = true
			case "Value":
				if valueAlreadyParsed {
					return errDuplicatedXMLTag
				}
				tag.Value = s
				valueAlreadyParsed = true
			default:

      when (ioe.cause) {
        is IllegalArgumentException -> {
          assertEquals("Android internal error", ioe.message)
        }
        is CertificateException -> {
          assertTrue(ioe.cause?.cause is IllegalArgumentException)
          assertEquals(
            true,
            ioe.cause
              ?.cause
              ?.message

E genéricos do módulo `typing`:

* `Union`
* `Optional`
* ...entre outros.

////

### Classes como tipos { #classes-as-types }

Você também pode declarar uma classe como o tipo de uma variável.

Digamos que você tenha uma classe `Person`, com um nome:

{* ../../docs_src/python_types/tutorial010_py39.py hl[1:3] *}

Então você pode declarar que uma variável é do tipo `Person`:

De plus, la meilleure approche était d'utiliser des normes déjà existantes.

Ainsi, avant même de commencer à coder **FastAPI**, j'ai passé plusieurs mois à étudier les spécifications d'OpenAPI, JSON Schema, OAuth2, etc. Comprendre leurs relations, leurs similarités et leurs différences.

## Conception

Ensuite, j'ai passé du temps à concevoir l'"API" de développeur que je voulais avoir en tant qu'utilisateur (en tant que développeur utilisant FastAPI).

		tierObjKey := ReservedMetadataPrefixLower + TransitionedObjectName
		tierObjVIDKey := ReservedMetadataPrefixLower + TransitionedVersionID

		for k, v := range j.MetaSys {
			switch k {
			case tierKey, tierObjKey, tierObjVIDKey:
				freeEntry.DeleteMarker.MetaSys[k] = v
			}
		}
		return freeEntry, true
	}
	return xlMetaV2Version{}, false
}

)

func initScramClient(args KafkaArgs, config *sarama.Config) {
	switch strings.ToLower(args.SASL.Mechanism) {
	case "sha512":
		config.Net.SASL.SCRAMClientGeneratorFunc = func() sarama.SCRAMClient { return &XDGSCRAMClient{HashGeneratorFcn: KafkaSHA512} }
		config.Net.SASL.Mechanism = sarama.SASLMechanism(sarama.SASLTypeSCRAMSHA512)
	case "sha256":

        wagon.clearExpectedContent();
        wagon.addExpectedContent("path", "lower-case-checksum");
        wagon.addExpectedContent("path.sha1", "2a25dc564a3b34f68237fc849066cbc7bb7a36a1");
        wagonManager.getArtifact(artifact, repo, null, false);

        wagon.clearExpectedContent();
        wagon.addExpectedContent("path", "upper-case-checksum");

- `aws:groups` - This is an array containing the group names, this value would point to group mappings for the user, use `jwt:groups` in case of OpenID connect and `ldap:groups` in case of AD/LDAP.

## Explore Further