*
   * This is typically invoked immediately before bytes are returned to the application. If the
   * response body is empty this is invoked immediately before returning that to the application.
   *
   * If the application closes the response body before attempting a read, this is invoked at the
   * time it is closed.
   *

For example you could use it to add metadata for a frontend user interface, etc.

///

/// info

OpenAPI 3.1.0 (used since FastAPI 0.99.0) added support for `examples`, which is part of the **JSON Schema** standard.

Before that, it only supported the keyword `example` with a single example. That is still supported by OpenAPI 3.1.0, but is deprecated and is not part of the JSON Schema standard. So you are encouraged to migrate `example` to `examples`. 🤓

                // this needs to be done before the reference to the remote hostname later
                transport.ensureConnected();

                if (waitForState(transport) == 2) {
                    // already connected
                    return null;
                }
                final int before = this.connectionState.getAndSet(1);
                if (before == 1) {

import java.util.Locale;

import org.codelibs.core.misc.DisposableUtil;
import org.codelibs.core.misc.LocaleUtil;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

/**
 * @author higa
 */
public class MessageFormatterTest {

    @Before
    public void setUp() throws Exception {
        LocaleUtil.setDefault(() -> Locale.JAPANESE);
    }

    @After

    latch.countDown();

    exec.shutdown();
    exec.awaitTermination(100, MILLISECONDS);
  }

  /**
   * Tests that all listeners complete, even if they were added before or after the future was
   * finishing. Also acts as a concurrency test to make sure the locking is done correctly when a
   * future is finishing so that no listeners can be lost.
   */

import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.TreeMap;
import org.jspecify.annotations.NullUnmarked;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

/** Tests for {@link MapIteratorCache} and {@link MapRetrievalCache}. */

from typing import Annotated

from fastapi import Depends, FastAPI

app = FastAPI()


def get_username():
    try:
        yield "Rick"
    finally:
        print("Cleanup up before response is sent")


@app.get("/users/me")
def get_user_me(username: Annotated[str, Depends(get_username, scope="function")]):

As said in the section [Alternatives](alternatives.md){.internal-link target=_blank}:

<blockquote markdown="1">

**FastAPI** wouldn't exist if not for the previous work of others.

There have been many tools created before that have helped inspire its creation.

I have been avoiding the creation of a new framework for several years. First I tried to solve all the features covered by **FastAPI** using many different frameworks, plug-ins, and tools.

     */
    void write(File output, Map<String, Object> options, Model model) throws IOException;

    /**
     * Writes the supplied model to the specified character writer. The writer will be automatically closed before the
     * method returns.
     *
     * @param output The writer to serialize the model to, must not be {@code null}.
     * @param options The options to use for serialization, may be {@code null} to use the default values.

     * existing values in the execution request that are controlled by the toolchains. Hence, it is expected that this
     * method is called on a new/empty execution request before the caller mutates it to fit its needs.
     *
     * @param request The execution request to populate, must not be {@code null}.
     * @param toolchains The toolchains to copy into the execution request, may be {@code null}.