# Base64 にしたバイトを含む JSON { #json-with-bytes-as-base64 }

アプリで JSON データの受信・送信が必要だが、その中にバイナリデータを含める必要がある場合は、base64 にエンコードできます。

## Base64 とファイル { #base64-vs-files }

バイナリデータのアップロードにはまず、JSON にエンコードする代わりに [Request Files](../tutorial/request-files.md) を、バイナリデータの送信には [カスタムレスポンス - FileResponse](./custom-response.md#fileresponse--fileresponse-) を使えるか検討してください。

JSON は UTF-8 でエンコードされた文字列のみを含められるため、生のバイト列は含められません。

        verify(transport).getDfsReferrals(eq(ctx), isNull(), eq("h"), eq("d"), eq(1));
    }

    // Signing modes: optional vs enforced
    @Test
    @DisplayName("isSigningOptional and isSigningEnforced reflect configuration")
    void signingModes() throws Exception {
        when(transport.isSigningOptional()).thenReturn(true);

`fastapi dev` コマンドにファイルパスを渡すこともでき、使用する FastAPI アプリオブジェクトを推測します:

```console
$ fastapi dev main.py
```

ただし、そのたびに `fastapi` コマンドを呼び出す際に正しいパスを渡す必要があります。

さらに、[VS Code 拡張機能](editor-support.md) や [FastAPI Cloud](https://fastapicloud.com) など、ほかのツールがそれを見つけられない場合があります。そのため、`pyproject.toml` の `entrypoint` を使用することを推奨します。

## `fastapi dev` { #fastapi-dev }

`fastapi dev` を実行すると、開発モードが有効になります。

        checkArgument(
            fromUpperBounds.length == toUpperBounds.length
                && fromLowerBounds.length == toLowerBounds.length,
            "Incompatible type: %s vs. %s",
            fromWildcardType,
            to);
        for (int i = 0; i < fromUpperBounds.length; i++) {
          populateTypeMappings(mappings, fromUpperBounds[i], toUpperBounds[i]);
        }

    // It really seems like this should be faster than TO_BYTE_ARRAY_NEW_STRING.  But it just isn't
    // my best guess is that the jdk authors have spent more time optimizing that callpath than this
    // one. (StringCoding$StringDecoder vs. StreamDecoder).  StringCoding has a ton of special cases
    // theoretically we could duplicate all that logic here to try to beat 'new String' or at least
    // come close.
    USING_DECODER_WITH_SIZE_HINT {
      @Override

    // It really seems like this should be faster than TO_BYTE_ARRAY_NEW_STRING.  But it just isn't
    // my best guess is that the jdk authors have spent more time optimizing that callpath than this
    // one. (StringCoding$StringDecoder vs. StreamDecoder).  StringCoding has a ton of special cases
    // theoretically we could duplicate all that logic here to try to beat 'new String' or at least
    // come close.
    USING_DECODER_WITH_SIZE_HINT {
      @Override

    }

    @Override
    public V[] createArray(int length) {
      // noinspection UnnecessaryLocalVariable
      V[] vs = ((TestMapGenerator<K, V>) mapGenerator.getInnerGenerator()).createValueArray(length);
      return vs;
    }

    @Override
    public Iterable<V> order(List<V> insertionOrder) {
      List<Entry<K, V>> orderedEntries =

이러한 선택적 의존성이 필요 없다면 `pip install fastapi`로 대신 설치할 수 있습니다.

standard 의존성은 설치하되 `fastapi-cloud-cli` 없이 설치하려면 `pip install "fastapi[standard-no-fastapi-cloud-cli]"`로 설치할 수 있습니다.

///

/// tip | 팁

FastAPI는 VS Code(및 Cursor)용 [공식 확장 프로그램](https://marketplace.visualstudio.com/items?itemName=FastAPILabs.fastapi-vscode)이 있습니다. 경로 처리 탐색기, 경로 처리 검색, 테스트에서의 CodeLens 탐색(테스트에서 정의로 바로 이동), FastAPI Cloud 배포와 로그 등 많은 기능을 에디터에서 바로 제공합니다.

///

    }

    @Override
    public V[] createArray(int length) {
      // noinspection UnnecessaryLocalVariable
      V[] vs = ((TestMapGenerator<K, V>) mapGenerator.getInnerGenerator()).createValueArray(length);
      return vs;
    }

    @Override
    public Iterable<V> order(List<V> insertionOrder) {
      List<Entry<K, V>> orderedEntries =

URLs that share the same address may also share the same underlying TCP socket connection. Sharing a connection has substantial performance benefits: lower latency, higher throughput (due to [TCP slow start](https://www.igvita.com/2011/10/20/faster-web-vs-tcp-slow-start/)) and conserved battery. OkHttp uses a [ConnectionPool](https://square.github.io/okhttp/5.x/okhttp/okhttp3/-connection-pool/) that automatically reuses HTTP/1.x connections and multiplexes HTTP/2 connections.