Django-Celery-SQS-S3-接收邮件

Question

我有一个Django应用程序，正在使用Celery，SQS和S3。当我使用Django，Celery和SQS运行以下函数时，该函数有效，并且每分钟应输出“ hello”。

from celery.task import periodic_task
from celery.schedules import crontab
@periodic_task(run_every=crontab(hour='*', minute='*', day_of_week="*"))
def print_hello():
    print('hello world')

但是该应用程序还链接到S3存储桶。每当有新文件保存到S3 a notification is sent to the SQS queue时。当通知消息发送到SQS队列时，就会发生此问题。当通知到达队列时，工作程序将失败。它会停止定期任务print_hello（），并显示以下错误消息：

[[2019-11-07 22：10：57,173：CRITICAL / MainProcess]无法恢复的错误：错误（“填充错误”）... parserinvoker / lib64 / python3.7 / base64.py“，第64行，第64行返回binascii.a2b_base64（s）binascii.Error：不正确的填充

然后退出。我一直在查看文档，并试图整周进行故障排除，但没有找到解决方案。如果包含配置问题，我将包含我的settings.py

Settings.py

BROKER_URL = "sqs://"
CELERY_ACCEPT_CONTENT = ['application/json']
CELERY_RESULT_SERIALIZER = 'json'
CELERY_TASK_SERIALIZER = 'json'
CELERY_DEFAULT_QUEUE = env('CELERY_DEFAULT_QUEUE')
CELERY_RESULT_BACKEND = None 
BROKER_TRANSPORT_OPTIONS = {
    'region': 'us-east-1',
    'polling_interval':20,
    'visibility_timeout': 3600,
    'task_default_queue': env('CELERY_DEFAULT_QUEUE'),
}

Answer 1

芹菜在队列上期望的json负载格式与SQS从s3接收的格式不同；为了正确处理这些消息，您可能希望有一个单独的定期任务，该任务会定期检查这些消息并耗尽s3通知队列，而不是将s3通知发送到celery broker队列。 s3消息正文将显示为described in the amazon documentation here。这是从S3发送到SQS的样本2.1记录：

   "Records":[  
      {  
         "eventVersion":"2.1",
         "eventSource":"aws:s3",
         "awsRegion":"us-west-2",
         "eventTime":The time, in ISO-8601 format, for example, 1970-01-01T00:00:00.000Z, when Amazon S3 finished processing the request,
         "eventName":"event-type",
         "userIdentity":{  
            "principalId":"Amazon-customer-ID-of-the-user-who-caused-the-event"
         },
         "requestParameters":{  
            "sourceIPAddress":"ip-address-where-request-came-from"
         },
         "responseElements":{  
            "x-amz-request-id":"Amazon S3 generated request ID",
            "x-amz-id-2":"Amazon S3 host that processed the request"
         },
         "s3":{  
            "s3SchemaVersion":"1.0",
            "configurationId":"ID found in the bucket notification configuration",
            "bucket":{  
               "name":"bucket-name",
               "ownerIdentity":{  
                  "principalId":"Amazon-customer-ID-of-the-bucket-owner"
               },
               "arn":"bucket-ARN"
            },
            "object":{  
               "key":"object-key",
               "size":object-size,
               "eTag":"object eTag",
               "versionId":"object version if bucket is versioning-enabled, otherwise null",
               "sequencer": "a string representation of a hexadecimal value used to determine event sequence, 
                   only used with PUTs and DELETEs"
            }
         },
         "glacierEventData": {
            "restoreEventData": {
               "lifecycleRestorationExpiryTime": "The time, in ISO-8601 format, for example, 1970-01-01T00:00:00.000Z, of Restore Expiry",
               "lifecycleRestoreStorageClass": "Source storage class for restore"
            }
         }
      }
   ]
}

芹菜消息格式looks like this。