使用 Amazon Braket 的進階記錄

您可以使用記錄器記錄整個任務處理程序。這些進階記錄技術可讓您查看背景輪詢，並建立記錄以供日後偵錯。

若要使用記錄器，建議您變更 poll_timeout_seconds和 poll_interval_seconds 參數，以便量子任務可以長時間執行，且量子任務狀態會持續記錄，並將結果儲存至檔案。您可以將此程式碼轉移到 Python 指令碼，而不是 Jupyter 筆記本，以便指令碼可以作為背景中的程序執行。

設定記錄器

首先，設定記錄器，將所有日誌自動寫入文字檔案中，如下列範例行所示。

# import the module
import logging
from datetime import datetime

# set filename for logs
log_file = 'device_logs-'+datetime.strftime(datetime.now(), '%Y%m%d%H%M%S')+'.txt'
print('Task info will be logged in:', log_file)

# create new logger object
logger = logging.getLogger("newLogger")

# configure to log to file device_logs.txt in the appending mode
logger.addHandler(logging.FileHandler(filename=log_file, mode='a'))

# add to file all log messages with level DEBUG or above
logger.setLevel(logging.DEBUG)

Task info will be logged in: device_logs-20200803203309.txt

建立並執行電路

現在您可以建立電路、將其提交至裝置以執行，並查看發生的情況，如本範例所示。

# define circuit
circ_log = Circuit().rx(0, 0.15).ry(1, 0.2).rz(2, 0.25).h(3).cnot(control=0, target=2).zz(1, 3, 0.15).x(4)
print(circ_log)
# define backend
device = AwsDevice("arn:aws:braket:::device/quantum-simulator/amazon/sv1")
# define what info to log
logger.info(
    device.run(circ_log, s3_location,
               poll_timeout_seconds=1200, poll_interval_seconds=0.25, logger=logger, shots=1000)
    .result().measurement_counts
)

檢查日誌檔案

您可以輸入下列命令來檢查寫入 檔案的內容。

# print logs
! cat {log_file}

Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: start polling for completion
Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: task status CREATED
Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: task status CREATED
Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: task status QUEUED
Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: task status RUNNING
Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: task status RUNNING
Task arn:aws:braket:us-west-2:123412341234:quantum-task/5088ec6c-89cf-4338-9750-9f5bb12a0dc4: task status COMPLETED
Counter({'00001': 493, '00011': 493, '01001': 5, '10111': 4, '01011': 3, '10101': 2})

從日誌檔案取得 ARN

從傳回的日誌檔案輸出，如先前範例所示，您可以取得 ARN 資訊。使用 ARN ID，您可以擷取已完成量子任務的結果。

# parse log file for arn
with open(log_file) as openfile:
    for line in openfile:
        for part in line.split():
            if "arn:" in part:
                arn = part
                break
# remove final semicolon in logs
arn = arn[:-1]

# with this arn you can restore again task from unique arn
task_load = AwsQuantumTask(arn=arn, aws_session=AwsSession())

# get results of task
result = task_load.result()