# Advanced User Guide { #advanced-user-guide }

## Additional Features { #additional-features }

The main [Tutorial - User Guide](../tutorial/index.md) should be enough to give you a tour through all the main features of **FastAPI**.

In the next sections you will see other options, configurations, and additional features.

/// tip

The next sections are **not necessarily "advanced"**.

///

## Advanced User Guide { #advanced-user-guide }

There is also an **Advanced User Guide** that you can read later after this **Tutorial - User guide**.

The **Advanced User Guide** builds on this one, uses the same concepts, and teaches you some extra features.

But you should first read the **Tutorial - User Guide** (what you are reading right now).

 [AccessHeadersJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/AccessHeaders.java
 [AccessHeadersKotlin]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/kt/AccessHeaders.kt
 [PostStringJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/PostString.java

/// tip

The next sections are **not necessarily "advanced"**.

And it's possible that for your use case, the solution is in one of them.

///

## Read the Tutorial first { #read-the-tutorial-first }

The next sections assume you already read the main [Tutorial - User Guide: Security](../../tutorial/security/index.md).

        final ChatMessage msg = createAssistantWithSources("A".repeat(1000), "Guide A", "Guide B", "Guide C");
        final String result = chatClient.testBuildAssistantHistoryContent(msg, "smart_summary", 500, 500);
        assertTrue(result.contains("[Referenced documents: Guide A, Guide B, Guide C]"));
        assertTrue(result.contains("...[omitted]..."));
    }

    @Test

      }
    ```

 [CustomTrustJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/CustomTrust.java
 [CustomTrustKotlin]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/kt/CustomTrust.kt
 [CertificatePinningJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/CertificatePinning.java

* Cover your code with tests. See the [Testing guide](contributing/Testing.md) for more information.
* Add documentation to the User Manual and DSL Reference (under [platforms/documentation/docs/src/docs](platforms/documentation/docs/src/docs/)).
* For error messages related changes, follow the [ErrorMessages Guide](contributing/ErrorMessages.md).

///

If you have an old FastAPI app with Pydantic v1, here I'll show you how to migrate it to Pydantic v2, and the **features in FastAPI 0.119.0** to help you with a gradual migration.

## Official Guide { #official-guide }

Pydantic has an official [Migration Guide](https://docs.pydantic.dev/latest/migration/) from v1 to v2.

It also includes what has changed, how validations are now more correct and strict, possible caveats, etc.

- **[Gradle Community Resources](https://community.gradle.org/resources/)**: Discover a range of resources, tutorials, and guides to support your Gradle journey, from foundational concepts to advanced practices.

---

### 💬 **Community Support & Resources**

The Gradle community offers a range of forums, documentation, and direct help to guide you through every step of your Gradle journey:

   *
   * <p>The recommended solution for finding the {@code minimum} of some values depends on the type
   * of your data and the number of elements you have. Read more in the Guava User Guide article on
   * <a href="https://github.com/google/guava/wiki/CollectionUtilitiesExplained#comparators">{@code
   * Comparators}</a>.
   *
   * @param a first value to compare, returned if less than or equal to b.