```
$ adb shell setprop log.tag.okhttp.Http2 DEBUG
$ adb shell setprop log.tag.okhttp.TaskRunner DEBUG
$ adb logcat '*:E' 'okhttp.Http2:D' 'okhttp.TaskRunner:D'
```

### HTTP/2 Frame Logging

This logs inbound (`<<`) and outbound (`>>`) frames for HTTP/2 connections.

```
[2020-01-01 00:00:00] >> CONNECTION 505249202a20485454502f322e300d0a0d0a534d0d0a0d0a
[2020-01-01 00:00:00] >> 0x00000000     6 SETTINGS

Blocking APIs may be inefficient because you hold a thread idle while waiting on the network. Threads are expensive because they have both a memory overhead and a context-switching overhead.

#### Framed protocols

pkg p1, type I interface, Name() string
pkg p1, type I interface, PackageTwoMeth()
pkg p1, type I interface, Set(string, int64)
pkg p1, type I interface, unexported methods
pkg p1, type MyInt int
pkg p1, type Namer interface { Name }
pkg p1, type Namer interface, Name() string
pkg p1, type Private interface, X()
pkg p1, type Private interface, unexported methods
pkg p1, type Private //deprecated
pkg p1, type Public interface { X, Y }

---

## Instala FastAPI

El primer paso es instalar FastAPI.

Para el tutorial, es posible que quieras instalarlo con todas las dependencias y características opcionales:

<div class="termy">

```console
$ pip install "fastapi[all]"

---> 100%

  }

  /** Maximum length of an outbound data frame.  */
  fun maxOutboundDataLength(): Int = writer.maxDataLength()

  /** Count of frames sent or received.  */
  fun frameCount(): Int = frameCount

  fun sendFrame(): Http2Writer {
    outFrames.add(OutFrame(frameCount++, bytesOut.size, false))
    return writer
  }

  /**
   * Shortens the last frame from its original length to `length`. This will cause the peer to

    "global.tracer.lightstep.address" "meshConfig.defaultConfig.tracing.lightstep.address"
    "global.tracer.lightstep.accessToken" "meshConfig.defaultConfig.tracing.lightstep.accessToken"
    "global.tracer.zipkin.address" "meshConfig.defaultConfig.tracing.zipkin.address"
    "global.tracer.stackdriver.debug" "meshConfig.defaultConfig.tracing.stackdriver.debug"

 *  * [onHeaders] (unless canceled)
 *  * [onData] (optional sequence of data frames)
 *
 * As a stream ID is scoped to a single HTTP/2 connection, implementations which target multiple
 * connections should expect repetition of stream IDs.
 *
 * Return true to request cancellation of a pushed stream.  Note that this does not guarantee
 * future frames won't arrive on the stream ID.
 */
interface PushObserver {
  /**

  /** Byte 0 reserved flag 3. Must be 0 unless negotiated otherwise. */
  internal const val B0_FLAG_RSV3 = 16

  /** Byte 0 mask for the frame opcode. */
  internal const val B0_MASK_OPCODE = 15

  /** Flag in the opcode which indicates a control frame. */
  internal const val OPCODE_FLAG_CONTROL = 8

  /**
   * Byte 1 flag for whether the payload data is masked.
   *
   * If this flag is set, the next four

                                    }
                                }
                            ),
                            ClassReader.EXPAND_FRAMES
                        )

                        classesDir.resolve(details.outputClassFilename).apply {
                            parentFile.mkdirs()
                            writeBytes(classWriter.toByteArray())

    /** HTTP/2: The peer must not send a PUSH_PROMISE frame when this is 0. */
    const val ENABLE_PUSH = 2

    /** Sender's maximum number of concurrent streams. */
    const val MAX_CONCURRENT_STREAMS = 4

    /** HTTP/2: Size in bytes of the largest frame payload the sender will accept. */
    const val MAX_FRAME_SIZE = 5