////


/// info

想进一步了解 <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic，请阅读其文档</a>.

///

整个 **FastAPI** 建立在 Pydantic 的基础之上。

实际上你将在 [教程 - 用户指南](tutorial/index.md){.internal-link target=_blank} 看到很多这种情况。

## **FastAPI** 中的类型提示

**FastAPI** 利用这些类型提示来做下面几件事。

使用 **FastAPI** 时用类型提示声明参数可以获得：

* **编辑器支持**。
* **类型检查**。

...并且 **FastAPI** 还会用这些类型声明来：

/// tip

Ви можете дізнатись більше про це у [документації про розгортування](deployment/index.md){.internal-link target=_blank}.

/// tip | Dica

Você pode aprender mais sobre isso na [documentação de deployment](deployment/index.md){.internal-link target=_blank}.

    }

    /**
     * Reads a null-terminated string from the buffer with bounds checking
     * @param src source buffer
     * @param srcIndex starting index in the buffer
     * @param srcEnd ending index boundary
     * @param maxLen maximum length to read
     * @param unicode whether to use Unicode encoding
     * @return read string
     */

{"id":3,"title":"Second Record","desc":"another text","nested":[[2,3,4],[7,8.5,9]]}`,
		},
		{
			name:       "index-wildcard-in",
			query:      `SELECT * from s3object s WHERE (8.5) IN s.nested[1][*]`,
			wantResult: `{"id":3,"title":"Second Record","desc":"another text","nested":[[2,3,4],[7,8.5,9]]}`,
		},
		{
			name:       "index-wildcard-in",
			query:      `SELECT * from s3object s WHERE (8.0+0.5) IN s.nested[1][*]`,

要生成客户端代码，您可以使用现在将要安装的命令行应用程序 `openapi-ts`。

因为它安装在本地项目中，所以您可能无法直接使用此命令，但您可以将其放在 `package.json` 文件中。

它可能看起来是这样的:

```JSON  hl_lines="7"
{
  "name": "frontend-app",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "generate-client": "openapi-ts --input http://localhost:8000/openapi.json --output ./src/client --client axios"
  },
  "author": "",
  "license": "",
  "devDependencies": {

    }
  }

  @Test fun nullHostileProtocolList() {
    val nullHostileProtocols =
      object : AbstractList<Protocol?>() {
        override val size: Int = 1

        override fun get(index: Int) = Protocol.HTTP_1_1

        override fun contains(element: Protocol?): Boolean {
          if (element == null) throw NullPointerException()
          return super.contains(element)
        }

    }

    char encode(int bits) {
      return chars[bits];
    }

    boolean isValidPaddingStartPosition(int index) {
      return validPadding[index % charsPerChunk];
    }

    boolean canDecode(char ch) {
      return ch <= Ascii.MAX && decodabet[ch] != -1;
    }

    int decode(char ch) throws DecodingException {

/// tip | Consejo

Puedes aprender más al respecto en la [documentación de despliegue](deployment/index.md){.internal-link target=_blank}.

///

## Casos de uso { #use-cases }

Algunos casos de uso incluyen:

* Convertir cuerpos de requests no-JSON a JSON (por ejemplo, <a href="https://msgpack.org/index.html" class="external-link" target="_blank">`msgpack`</a>).
* Descomprimir cuerpos de requests comprimidos con gzip.
* Registrar automáticamente todos los request bodies.