# Reference - Code API

Here's the reference or code API, the classes, functions, parameters, attributes, and
all the FastAPI parts you can use in your applications.

If you want to **learn FastAPI** you are much better off reading the

Sie sollten eine sehr lange JavaScript-Datei für **ReDoc** sehen.

Sie könnte beginnen mit etwas wie:

```JavaScript
/*!
 * ReDoc - OpenAPI/Swagger-generated API Reference Documentation
 * -------------------------------------------------------------
 *   Version: "2.0.0-rc.18"
 *   Repo: https://github.com/Redocly/redoc
 */
!function(e,t){"object"==typeof exports&&"object"==typeof m

就能看到 **ReDoc** 的 JavaScript 文件。

该文件开头如下：

```JavaScript
/*!
 * ReDoc - OpenAPI/Swagger-generated API Reference Documentation
 * -------------------------------------------------------------
 *   Version: "2.0.0-rc.18"
 *   Repo: https://github.com/Redocly/redoc
 */
!function(e,t){"object"==typeof exports&&"object"==typeof m

### ⚙️ 🔑 👨‍💼 🔗 ⏮️ `yield`

!!! warning
    👉, 🌅 ⚖️ 🌘, "🏧" 💭.

    🚥 👆 ▶️ ⏮️ **FastAPI** 👆 💪 💚 🚶 ⚫️ 🔜.

🐍, 👆 💪 ✍ 🔑 👨‍💼 <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">🏗 🎓 ⏮️ 2️⃣ 👩‍🔬: `__enter__()` &amp; `__exit__()`</a>.

👆 💪 ⚙️ 👫 🔘 **FastAPI** 🔗 ⏮️ `yield` ⚙️
`with` ⚖️ `async with` 📄 🔘 🔗 🔢:

    - how-to/nosql-databases-couchbase.md
- Reference (Code API):
  - reference/index.md
  - reference/fastapi.md
  - reference/parameters.md
  - reference/status.md
  - reference/uploadfile.md
  - reference/exceptions.md
  - reference/dependencies.md
  - reference/apirouter.md
  - reference/background.md
  - reference/request.md
  - reference/websockets.md
  - reference/httpconnection.md
  - reference/response.md

# `APIRouter` class

Here's the reference information for the `APIRouter` class, with all its parameters, attributes and methods.

You can import the `APIRouter` class directly from `fastapi`:

```python
from fastapi import APIRouter
```

::: fastapi.APIRouter
    options:
        members:
            - websocket
            - include_router
            - get
            - put
            - post
            - delete

# `FastAPI` class

Here's the reference information for the `FastAPI` class, with all its parameters, attributes and methods.

You can import the `FastAPI` class directly from `fastapi`:

```python
from fastapi import FastAPI
```

::: fastapi.FastAPI
    options:
        members:
            - openapi_version
            - webhooks
            - state
            - dependency_overrides
            - openapi

# Dependencies - `Depends()` and `Security()`

## `Depends()`

Dependencies are handled mainly with the special function `Depends()` that takes a callable.

Here is the reference for it and its parameters.

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

Each section gradually builds on the previous ones, but it's structured to separate topics, so that you can go directly to any specific one to solve your specific API needs.

It is also built to work as a future reference.

So you can come back and see exactly what you need.

## Run the code

All the code blocks can be copied and used directly (they are actually tested Python files).

            * A key `schema`, that has as the value the JSON Schema from the model, here's the correct place.
                * **FastAPI** adds a reference here to the global JSON Schemas in another place in your OpenAPI instead of including it directly. This way, other applications and clients can use those JSON Schemas directly, provide better code generation tools, etc.