OpenAPI has a way to define multiple security "schemes".

By using them, you can take advantage of all these standard-based tools, including these interactive documentation systems.

OpenAPI defines the following security schemes:

* `apiKey`: an application specific key that can come from:
    * A query parameter.
    * A header.

///

In HTTP, you send a numeric status code of 3 digits as part of the response.

These status codes have a name associated to recognize them, but the important part is the number.

In short:

* `100 - 199` are for "Information". You rarely use them directly.  Responses with these status codes cannot have a body.
* **`200 - 299`** are for "Successful" responses. These are the ones you would use the most.

FastAPI includes some default configuration parameters appropriate for most of the use cases.

It includes these default configurations:

{* ../../fastapi/openapi/docs.py ln[9:24] hl[18:24] *}

You can override any of them by setting a different value in the argument `swagger_ui_parameters`.

For example, to disable `deepLinking` you could pass these settings to `swagger_ui_parameters`:

{* ../../docs_src/configure_swagger_ui/tutorial003_py39.py hl[3] *}

{* ../../docs_src/dependencies/tutorial006_an_py39.py hl[19] *}

These dependencies will be executed/solved the same way as normal dependencies. But their value (if they return any) won't be passed to your *path operation function*.

/// tip

Some editors check for unused function parameters, and show them as errors.

      cache.getUnchecked(1);
      cache.getUnchecked(2);

      Set<Object> keys = cache.asMap().keySet();
      // We don't know whether these are still in the cache, so we can't assert on the return
      // values of these removes, but the cache should be empty after the removes, regardless.
      keys.remove(1);
      keys.remove(2);
      assertThat(keys.remove(null)).isFalse();

      cache.getUnchecked(1);
      cache.getUnchecked(2);

      Set<Object> keys = cache.asMap().keySet();
      // We don't know whether these are still in the cache, so we can't assert on the return
      // values of these removes, but the cache should be empty after the removes, regardless.
      keys.remove(1);
      keys.remove(2);
      assertThat(keys.remove(null)).isFalse();

ml_dtypes >= 0.5.1, < 0.6.0
auditwheel >= 6.1.0
# Install tensorboard, and keras
# Note that here we want the latest version that matches TF major.minor version
# Note that we must use nightly here as these are used in nightly jobs
# For release jobs, we will pin these on the release branch
keras-nightly ~= 3.10.0.dev
tb-nightly ~= 2.20.0.a
# For new protobuf, if V.x.y is gencode version, then runtime version U must be
# V <= U <= V+1

These types that have internal types are called "**generic**" types. And it's possible to declare them, even with their internal types.

To declare those types and the internal types, you can use the standard Python module `typing`. It exists specifically to support these type hints.

#### Newer versions of Python { #newer-versions-of-python }

The OAuth2 specification defines "scopes" as a list of strings separated by spaces.

The content of each of these strings can have any format, but should not contain spaces.

These scopes represent "permissions".

In OpenAPI (e.g. the API docs), you can define "security schemes".

When one of these security schemes uses OAuth2, you can also declare and use scopes.

Each "scope" is just a string (without spaces).

But you can have thousands of endpoints (*path operations*) using the same security system.

And all of them (or any portion of them that you want) can take advantage of re-using these dependencies or any other dependencies you create.

And all these thousands of *path operations* can be as small as 3 lines:

{* ../../docs_src/security/tutorial002_an_py310.py hl[30:32] *}

## Recap { #recap }