* But it needs authentication for that specific endpoint.
    * So, to authenticate with our API, it sends a header `Authorization` with a value of `Bearer ` plus the token.
    * If the token contains `foobar`, the content of the `Authorization` header would be: `Bearer foobar`.

## **FastAPI**'s `OAuth2PasswordBearer` { #fastapis-oauth2passwordbearer }

			authString:    "NoV2Prefix",
			expectedError: ErrSignatureVersionNotSupported,
		},
		// Test case - 3.
		// Test case with missing parts in the Auth string.
		// below is the correct format of V2 Authorization header.
		// Authorization = "AWS" + " " + AWSAccessKeyId + ":" + Signature
		{
			authString:    signV2Algorithm,
			expectedError: ErrMissingFields,
		},
		// Test case - 4.
		// Test case with signature part missing.

* 🕸 🏪 👈 🤝 🍕 👱.
* 👩‍💻 🖊 🕸 🚶 ➕1️⃣ 📄 🕸 🕸 📱.
* 🕸 💪 ☕ 🌅 💽 ⚪️➡️ 🛠️.
    * ✋️ ⚫️ 💪 🤝 👈 🎯 🔗.
    * , 🔓 ⏮️ 👆 🛠️, ⚫️ 📨 🎚 `Authorization` ⏮️ 💲 `Bearer ` ➕ 🤝.
    * 🚥 🤝 🔌 `foobar`, 🎚 `Authorization` 🎚 🔜: `Bearer foobar`.

## **FastAPI**'Ⓜ `OAuth2PasswordBearer`

**FastAPI** 🚚 📚 🧰, 🎏 🎚 ⚛, 🛠️ 👫 💂‍♂ ⚒.

the potential to leak sensitive information such as "Authorization" or "Cookie" headers and the
contents of request and response bodies. This data should only be logged in a controlled way or in
a non-production environment.

You can redact headers that may contain sensitive information by calling `redactHeader()`.
```java
logging.redactHeader("Authorization");
logging.redactHeader("Cookie");
```

Download
--------

    * Pero necesita autenticación para ese endpoint específico.
    * Así que, para autenticarse con nuestra API, envía un `header` `Authorization` con un valor de `Bearer ` más el token.
    * Si el token contiene `foobar`, el contenido del `header` `Authorization` sería: `Bearer foobar`.

## `OAuth2PasswordBearer` de **FastAPI**

          @Throws(IOException::class)
          override fun authenticate(
            route: Route?,
            response: Response,
          ): Request? {
            if (response.request.header("Authorization") != null) {
              return null // Give up, we've already attempted to authenticate.
            }

            println("Authenticating for response: $response")

            url.toUrl(),
            Authenticator.RequestorType.SERVER,
          )
        }

      if (auth != null) {
        val credentialHeader = if (proxyAuthorization) "Proxy-Authorization" else "Authorization"
        val credential =
          Credentials.basic(
            auth.userName,
            String(auth.password),
            challenge.charset,
          )
        return request

                File("docs/images/logo-square.png").asRequestBody(MEDIA_TYPE_PNG))
            .build()

        val request = Request.Builder()
            .header("Authorization", "Client-ID $IMGUR_CLIENT_ID")
            .url("https://api.imgur.com/3/image")
            .post(requestBody)
            .build()

        client.newCall(request).execute().use { response ->

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

For many scenarios, you can handle security (authorization, authentication, etc.) with dependencies, using `Depends()`.

But when you want to also declare OAuth2 scopes, you can use `Security()` instead of `Depends()`.

You can import `Security()` directly from `fastapi`:

                authHeader = "WWW-Authenticate";
                this.authProperty = "Authorization";
            } else {
                authHeader = "Proxy-Authenticate";
                this.authProperty = "Proxy-Authorization";
            }
            String authorization = null;
            final List<String> methods = getHeaderFields0().get(authHeader);
            if (methods == null) {