## Development Commands

### Setup
```bash
# Download OpenSearch plugins (required before first build)
mvn antrun:run

# Generate DBFlute source code (when schema changes)
mvn dbflute:download  # One-time setup
mvn dbflute:freegen
mvn license:format
```

### Build
```bash
# Standard build
mvn package

# Clean build
mvn clean package

# Build distribution packages

  }

  /** Returns {@code null} as any type, even one that does not include {@code null}. */
  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T unsafeNull() {
    return null;
  }

  private NullnessCasts() {}

    }
  }

  // fails in Maven with 64-bit JDK: https://github.com/google/guava/issues/1568

  // A simple type whose .toString() will return the same value each time, but without maintaining
  // a strong reference to that value.
  static class Key {
    private final int value;
    private WeakReference<String> toString;

    Key(int value) {
      this.value = value;

  }

  /** Returns {@code null} as any type, even one that does not include {@code null}. */
  @SuppressWarnings({"nullness", "TypeParameterUnusedInFormals", "ReturnMissingNullable"})
  // The warnings are legitimate. Each time we use this method, we document why.
  @ParametricNullness
  static <T extends @Nullable Object> T unsafeNull() {
    return null;
  }

  private NullnessCasts() {}

You can create production applications with **FastAPI** right now (and you have probably been doing it for some time), you just have to make sure that you use a version that works correctly with the rest of your code.

## Pin your `fastapi` version { #pin-your-fastapi-version }

{* ../../docs_src/custom_request_and_route/tutorial003_py310.py hl[26] *}

В этом примере *операции пути*, объявленные в `router`, будут использовать пользовательский класс `TimedRoute` и получат дополнительный HTTP-заголовок `X-Response-Time` в ответе с временем, затраченным на формирование ответа:

## Second dependency, "dependable" and "dependant" { #second-dependency-dependable-and-dependant }

Then you can create another dependency function (a "dependable") that at the same time declares a dependency of its own (so it is a "dependant" too):

{* ../../docs_src/dependencies/tutorial005_an_py310.py hl[13] *}

Let's focus on the parameters declared:

To do this, use `yield` instead of `return`, and write the extra steps (code) after.

/// tip

Make sure to use `yield` one single time per dependency.

///

/// note | Technical Details

Any function that is valid to use with:

import kotlin.text.Charsets.UTF_16BE
import kotlin.text.Charsets.UTF_16LE
import kotlin.text.Charsets.UTF_32BE
import kotlin.text.Charsets.UTF_32LE
import kotlin.text.Charsets.UTF_8
import kotlin.time.Duration
import okhttp3.Dispatcher
import okhttp3.EventListener
import okhttp3.Headers
import okhttp3.HttpUrl
import okhttp3.HttpUrl.Companion.defaultPort
import okhttp3.OkHttpClient
import okhttp3.Response

    fun cancel()
  }

  companion object {
    /**
     * The timeout to use while discarding a stream of input data. Since this is used for connection
     * reuse, this timeout should be significantly less than the time it takes to establish a new
     * connection.
     */
    const val DISCARD_STREAM_TIMEOUT_MILLIS = 100
  }