## Create a task function

Create a function to be run as the background task.

It is just a standard function that can receive parameters.

It can be an `async def` or normal `def` function, **FastAPI** will know how to handle it correctly.

In this case, the task function will write to a file (simulating sending an email).

  EXPECT_EQ(TF_GetCode(status), TF_OK) << TF_Message(status);

  const char task0_name[] = "/job:localhost/replica:0/task:0/device:CPU:0";
  const char task1_name[] = "/job:localhost/replica:0/task:1/device:CPU:0";
  const char task2_name[] = "/job:localhost/replica:0/task:2/device:CPU:0";

  // Create one variable per task.
  TFE_TensorHandle* h0 = TestVariable(ctx, 1.0, task1_name);
  TFE_TensorHandle* h1 = TestVariable(ctx, 2.0, task2_name);

            directExecutor());

    // Wait for the first task to be started in the background. It will block until we explicitly
    // stop it.
    blockingCallable.waitForStart();

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    assertThat(future2.isDone()).isFalse();

    // Stop the first task. The second task should then run.
    blockingCallable.stop();

                final Tuple3<String, String, String> task = generator.createTask(path, docMap);
                if (task != null) {
                    if (logger.isDebugEnabled()) {
                        logger.debug("Add thumbnail task: {}", task);
                    }
                    if (!thumbnailTaskQueue.offer(task)) {
                        logger.warn("Failed to add thumbnail task: {}", task);
                    }

# Atrás de um Proxy

Em algumas situações, você pode precisar usar um servidor **proxy** como Traefik ou Nginx com uma configuração que adiciona um prefixo de caminho extra que não é visto pela sua aplicação.

Nesses casos, você pode usar `root_path` para configurar sua aplicação.

O `root_path` é um mecanismo fornecido pela especificação ASGI (que o FastAPI utiliza, através do Starlette).

O `root_path` é usado para lidar com esses casos específicos.

     * information that is available at the point the problem occurs and as such merely serves as best effort
     * to provide information to the user to track the problem back to its origin.
     *
     * @return The hint about the source of the problem or an empty string if unknown, never {@code null}.
     */
    String getSource();

    /**

    assertFalse(task.isDone());
    assertFalse(task.isCancelled());

    // Start the task to put it in the RUNNING state.  Have to use a separate
    // thread because the task will block on the task latch after unblocking
    // the run latch.
    exec.execute(task);
    runLatch.await();
    assertEquals(1, listenerLatch.getCount());
    assertFalse(task.isDone());
    assertFalse(task.isCancelled());

              }
            });
    Runnable task =
        new Runnable() {
          @Override
          public void run() {
            numCalls.incrementAndGet();
          }
        };
    assertThrows(RejectedExecutionException.class, () -> executor.execute(task));
    assertEquals(0, numCalls.get());
    reject.set(false);
    executor.execute(task);
    assertEquals(1, numCalls.get());
  }

            AbstractService service, ScheduledExecutorService executor, Runnable task) {
          return new FutureAsCancellable(
              executor.scheduleWithFixedDelay(task, initialDelay, delay, unit));
        }
      };
    }

    /**
     * Returns a {@link Scheduler} that schedules the task using the {@link
     * ScheduledExecutorService#scheduleAtFixedRate} method.
     *

  EXPECT_EQ(TF_OK, TF_GetCode(status)) << TF_Message(status);

  const char remote_device_name[] =
      "/job:localhost/replica:0/task:1/device:CPU:0";
  const char local_device_name[] =
      "/job:localhost/replica:0/task:0/device:CPU:0";
  CheckRemoteMatMulExecutesOK(ctx, remote_device_name, local_device_name);

  TFE_Executor* executor = TFE_ContextGetExecutorForThread(ctx);