{* ../../docs_src/stream_data/tutorial001_py310.py ln[44:47] hl[47] *}

## A Custom `PNGStreamingResponse` { #a-custom-pngstreamingresponse }

In the examples above, the data bytes were streamed, but the response didn't have a `Content-Type` header, so the client didn't know what type of data it was receiving.

 *   <li>Supports a copy-free {@link #subArray} view, so methods that accept this type don't need to
 *       add overloads that accept start and end indexes.
 *   <li>Can be streamed without "breaking the chain": {@code foo.getBarLongs().stream()...}.
 *   <li>Access to all collection-based utilities via {@link #asList} (though at the cost of
 *       allocating garbage).
 * </ul>
 *

 *   <li>Supports a copy-free {@link #subArray} view, so methods that accept this type don't need to
 *       add overloads that accept start and end indexes.
 *   <li>Can be streamed without "breaking the chain": {@code foo.getBarDoubles().stream()...}.
 *   <li>Access to all collection-based utilities via {@link #asList} (though at the cost of
 *       allocating garbage).
 * </ul>
 *

 *   <li>Supports a copy-free {@link #subArray} view, so methods that accept this type don't need to
 *       add overloads that accept start and end indexes.
 *   <li>Can be streamed without "breaking the chain": {@code foo.getBarInts().stream()...}.
 *   <li>Access to all collection-based utilities via {@link #asList} (though at the cost of
 *       allocating garbage).
 * </ul>
 *

    backwards-incompatible API changes that may impact early adopters of this alpha API.

 *  New: `mockwebserver3.Stream` for duplex streams.

 *  New: `mockwebserver3.MockResponseBody` for streamed response bodies.

 *  New: `mockwebserver3.MockResponse` is now immutable, with a `Builder`.

 *  New: `mockwebserver3.RecordedRequest.handshakeServerNames` returns the SNI (Server Name

				Mode:     0666,
			},
		},
	},
	// Tests that we verify (and accept valid) crc32s on files
	// with crc32s in their file header (not in data descriptors)
	{
		Name: "crc32-not-streamed.zip",
		File: []ZipTestFile{
			{
				Name:     "foo.txt",
				Content:  []byte("foo\n"),
				Modified: time.Date(2012, 3, 8, 16, 59, 10, 0, timeZone(-8*time.Hour)),
				Mode:     0644,
			},
			{

            ),
          )
        assertContent("B", response)
        break
      } catch (socketException: IOException) {
        // If there's a socket exception, this must have a streamed request body.
        assertThat(j).isEqualTo(0)
        assertThat(transferKind).isIn(TransferKind.CHUNKED, TransferKind.FIXED_LENGTH)
      }
    }
    val requestA = server.takeRequest()

      TYPE_DATA -> readData(handler, length, flags, streamId)
      TYPE_HEADERS -> readHeaders(handler, length, flags, streamId)
      TYPE_PRIORITY -> readPriority(handler, length, flags, streamId)
      TYPE_RST_STREAM -> readRstStream(handler, length, flags, streamId)
      TYPE_SETTINGS -> readSettings(handler, length, flags, streamId)
      TYPE_PUSH_PROMISE -> readPushPromise(handler, length, flags, streamId)

    streamId: Int,
    requestHeaders: List<Header>,
  ) {
    withLock {
      if (streamId in currentPushRequests) {
        writeSynResetLater(streamId, ErrorCode.PROTOCOL_ERROR)
        return
      }
      currentPushRequests.add(streamId)
    }
    pushQueue.execute("$connectionName[$streamId] onRequest") {
      val cancel = pushObserver.onRequest(streamId, requestHeaders)
      ignoreIoExceptions {

# Daten streamen { #stream-data }

Wenn Sie Daten streamen möchten, die als JSON strukturiert werden können, sollten Sie [JSON Lines streamen](../tutorial/stream-json-lines.md).

Wenn Sie jedoch **reine Binärdaten** oder Strings streamen möchten, so können Sie es machen.

/// info | Info

Hinzugefügt in FastAPI 0.134.0.

///

## Anwendungsfälle { #use-cases }