* Documentation automatique des modèles de données avec <a href="http://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a> (comme OpenAPI est aussi basée sur JSON Schema).
* Conçue avec ces standards après une analyse méticuleuse. Plutôt qu'en rajoutant des surcouches après coup.

But it was created before there existed Python type hints. So, to define every <abbr title="the definition of how data should be formed">schema</abbr> you need to use specific utils and classes provided by Marshmallow.

/// check | "Inspired **FastAPI** to"

Use code to define "schemas" that provide data types and validation, automatically.

///

#### Überprüfen Sie die `openapi.json`

Falls Sie wissen möchten, wie das rohe OpenAPI-Schema aussieht: FastAPI generiert automatisch ein JSON (Schema) mit den Beschreibungen Ihrer gesamten API.

			cacheStore.Store(embeddedCacheKey, true)
			if field.EmbeddedSchema, err = getOrParse(fieldValue.Interface(), cacheStore, embeddedNamer{Table: schema.Table, Namer: schema.namer}); err != nil {
				schema.err = err
			}

			for _, ef := range field.EmbeddedSchema.Fields {
				ef.Schema = schema
				ef.OwnerSchema = field.EmbeddedSchema
				ef.BindNames = append([]string{fieldStruct.Name}, ef.BindNames...)

* Automatic data model documentation with <a href="https://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a> (as OpenAPI itself is based on JSON Schema).
* Designed around these standards, after a meticulous study. Instead of an afterthought layer on top.

## 创建 Pydantic 模型

现在让我们查看一下文件`sql_app/schemas.py`。

/// tip

为了避免 SQLAlchemy*模型*和 Pydantic*模型*之间的混淆，我们将有`models.py`（SQLAlchemy 模型的文件）和`schemas.py`（ Pydantic 模型的文件）。

这些 Pydantic 模型或多或少地定义了一个“schema”（一个有效的数据形状）。

因此，这将帮助我们在使用两者时避免混淆。

///

### 创建初始 Pydantic*模型*/模式

创建一个`ItemBase`和`UserBase`Pydantic*模型*（或者我们说“schema”），他们拥有创建或读取数据时具有的共同属性。

### API Docs

If you go to the API docs, you will see that it has the **schemas** for the data to be sent in requests and received in responses:

<img src="/img/tutorial/generate-clients/image01.png">

You can see those schemas because they were declared with the models in the app.

That information is available in the app's **OpenAPI schema**, and then shown in the API docs (by Swagger UI).

  // `distinguisherMethod` defines how to compute the flow distinguisher for requests that match this schema.
  // `nil` specifies that the distinguisher is disabled and thus will always be the empty string.
  // +optional
  optional FlowDistinguisherMethod distinguisherMethod = 3;

  // `rules` describes which requests will match this flow schema. This FlowSchema matches a request if and only if
  // at least one member of rules matches the request.

                        security_schemes
                    )
                if path_definitions:
                    definitions.update(path_definitions)
    if definitions:
        components["schemas"] = {k: definitions[k] for k in sorted(definitions)}
    if components:
        output["components"] = components
    output["paths"] = paths
    if webhook_paths:
        output["webhooks"] = webhook_paths

* Otomatik olarak data modelinin <a href="http://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a> ile beraber dokümante edilmesi (OpenAPI'n kendisi zaten JSON Schema'ya dayanıyor).