* failing tasks only, to not use up unnecessary disk space on Team City. This also improves the performance of
 * artifact publishing by reducing the artifacts and packaging reports that consist of multiple files.
 *
 * Reducing the number of reports also makes it easier to find the important ones when analysing a failed build in
 * Team City.
 */

## License identifier { #license-identifier }

Since OpenAPI 3.1.0 and FastAPI 0.99.0, you can also set the `license_info` with an `identifier` instead of a `url`.

For example:

{* ../../docs_src/metadata/tutorial001_1_py39.py hl[31] *}

## Metadata for tags { #metadata-for-tags }

You can also add additional metadata for the different tags used to group your path operations with the parameter `openapi_tags`.

<img src="/img/python-types/image04.png">

Now you know that you have to fix it, convert `age` to a string with `str(age)`:

{* ../../docs_src/python_types/tutorial004_py39.py hl[2] *}

## Declaring types { #declaring-types }

You just saw the main place to declare type hints. As function parameters.

///

Angenommen, Sie möchten den Query-Parameter `q` als erforderlichen `str` deklarieren.

Und Sie müssen sonst nichts anderes für diesen Parameter deklarieren, Sie brauchen also `Query` nicht wirklich.

Aber Sie müssen dennoch `Path` für den `item_id`-Pfad-Parameter verwenden. Und aus irgendeinem Grund möchten Sie `Annotated` nicht verwenden.

# Using Dataclasses { #using-dataclasses }

FastAPI is built on top of **Pydantic**, and I have been showing you how to use Pydantic models to declare requests and responses.

But FastAPI also supports using <a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a> the same way:

{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

You never call those functions directly. They are called by your framework (in this case, **FastAPI**).

With the Dependency Injection system, you can also tell **FastAPI** that your *path operation function* also "depends" on something else that should be executed before your *path operation function*, and **FastAPI** will take care of executing it and "injecting" the results.

And then you can also have a path `/users/{user_id}` to get data about a specific user by some user ID.

Because *path operations* are evaluated in order, you need to make sure that the path for `/users/me` is declared before the one for `/users/{user_id}`:

{* ../../docs_src/path_params/tutorial003_py39.py hl[6,11] *}

When using `Field()` with Pydantic models, you can also declare additional `examples`:

{* ../../docs_src/schema_extra_example/tutorial002_py310.py hl[2,8:11] *}

## `examples` in JSON Schema - OpenAPI { #examples-in-json-schema-openapi }

When using any of:

* `Path()`
* `Query()`
* `Header()`
* `Cookie()`
* `Body()`
* `Form()`
* `File()`

Stellen wir uns vor, Sie haben eine Datenbank `fake_db`, die nur JSON-kompatible Daten entgegennimmt.

Sie akzeptiert zum Beispiel keine `datetime`-Objekte, da die nicht kompatibel mit JSON sind.

Ein `datetime`-Objekt müsste also in einen `str` umgewandelt werden, der die Daten im <a href="https://en.wikipedia.org/wiki/ISO_8601" class="external-link" target="_blank">ISO-Format</a> enthält.

But Facebook login doesn't support OpenID Connect. It has its own flavor of OAuth2.

### OpenID (not "OpenID Connect") { #openid-not-openid-connect }

There was also an "OpenID" specification. That tried to solve the same thing as **OpenID Connect**, but was not based on OAuth2.

So, it was a complete additional system.

It is not very popular or used nowadays.

## OpenAPI { #openapi }