/// tip

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

Using these `dependencies` in the *path operation decorator* you can make sure they are executed while avoiding editor/tooling errors.

**FastAPI** will make sure to read that data from the right place instead of JSON.

/// note | Technical Details

Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded`.

But when the form includes files, it is encoded as `multipart/form-data`. You'll read about handling files in the next chapter.

 *
 * <p>The core interface used to represent caches is {@link Cache}. In-memory caches can be
 * configured and created using {@link CacheBuilder}, with cache entries being loaded by {@link
 * CacheLoader}. Statistics about cache performance are exposed using {@link CacheStats}.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/CachesExplained">caches</a>.
 *

    * So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would if you didn't use it (as you would have to...

 *     unless it is constrained by using a method like {@link #nodeOrder}, or the builder is
 *     constructed based on an existing {@code ValueGraph} using {@link #from(ValueGraph)}.
 * @param <V> The most general value type this builder will support. This is normally {@code Object}
 *     unless the builder is constructed based on an existing {@code Graph} using {@link
 *     #from(ValueGraph)}.
 * @since 20.0
 */
@Beta

要運行你的 FastAPI 應用程式來進行開發，你可以使用 `fastapi dev` 命令：

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:single">main.py</u>
<font color="#3465A4">INFO    </font> Using path <font color="#3465A4">main.py</font>
<font color="#3465A4">INFO    </font> Resolved absolute path <font color="#75507B">/home/user/code/awesomeapp/</font><font color="#AD7FA8">main.py</font>

-   In such situations, we may request you to make further changes to your PR
    for the tests to pass.
-   Once the tests pass, we now bring all the code into the internal code base,
    using a job called "copybara".

**5. Copy to Google Internal codebase and run internal CI**

-   Once the PR is in the Google codebase, we make sure it integrates well with
    its dependencies and the rest of the system.

        DEFAULT_TARGET_INFORMATION = targetInfo;
    }

    /**
     * Creates a Type-2 message using default values from the current
     * environment.
     */
    public Type2Message() {
        this(getDefaultFlags(), null, null);
    }

    /**
     * Creates a Type-2 message in response to the given Type-1 message
     * using default values from the current environment.
     *

import org.slf4j.LoggerFactory;

/**
 * Secure credential storage with encryption at rest.
 *
 * Provides secure storage of passwords and other sensitive credentials
 * using AES-GCM encryption with PBKDF2 key derivation.
 *
 * Features:
 * - Encrypts credentials at rest using AES-256-GCM
 * - Uses PBKDF2 for key derivation from master password
 * - Secure wiping of sensitive data
 * - Thread-safe operations
 * - Protection against timing attacks

If you integrate your API with an OAuth2 provider, you will be able to authenticate and come back to the API docs with the acquired credentials. And interact with it using the real OAuth2 authentication.

Swagger UI will handle it behind the scenes for you, but it needs this "redirect" helper.

///

### Create a *path operation* to test it { #create-a-path-operation-to-test-it }