测试AWS Lambda处理程序功能时出错:事件和上下文参数的数据格式

时间:2019-02-25 23:41:51

标签: python-3.x amazon-web-services aws-lambda aws-lex

我从博客中获得了以下代码,该代码获取了今天的比特币价格。我可以从AWS Lex控制台访问此Lambda函数,并测试该机器人以获得今天的价格。

"""
Lexbot Lambda handler.
"""
from urllib.request import Request, urlopen
import json

def get_bitcoin_price(date):
    print('get_bitcoin_price, date = ' + str(date))
    request = Request('https://rest.coinapi.io/v1/ohlcv/BITSTAMP_SPOT_BTC_USD/latest?period_id=1DAY&limit=1&time_start={}'.format(date))
    request.add_header('X-CoinAPI-Key', 'E4107FA4-A508-448A-XXX')
    response = json.loads(urlopen(request).read())
    return response[0]['price_close']

def lambda_handler(event, context):
    print('received request: ' + str(event))
    date_input = event['currentIntent']['slots']['Date']
    btc_price = get_bitcoin_price(date_input)
    response = {
        "dialogAction": {
            "type": "Close",
            "fulfillmentState": "Fulfilled",
            "message": {
              "contentType": "SSML",
              "content": "Bitcoin's price was {price} dollars".format(price=btc_price)
            },
        }
    }
    print('result = ' + str(response))
    return response

但是当我从AWS Lex控制台测试功能时,出现以下错误:

 Response:
{
  "errorMessage": "'currentIntent'",
  "errorType": "KeyError",
  "stackTrace": [
    [
      "/var/task/lambda_function.py",
      18,
      "lambda_handler",
      "date_input = event['currentIntent']['slots']['Date']"
    ]
  ]
}

Request ID:
"2488187a-2b76-47ba-b884-b8aae7e7a25d"

Function Logs:
START RequestId: 2488187a-2b76-47ba-b884-b8aae7e7a25d Version: $LATEST
received request: {'Date': 'Feb 22'}
'currentIntent': KeyError
Traceback (most recent call last):
  File "/var/task/lambda_function.py", line 18, in lambda_handler
    date_input = event['currentIntent']['slots']['Date']
KeyError: 'currentIntent'

如何在AWS Lambda控制台中测试功能? “ lambda_handler”函数,“事件”和“上下文”的格式是什么?另外,这里的“背景”是什么?

在我的情况下,我应该通过什么作为“事件”和“上下文”?

1 个答案:

答案 0 :(得分:2)

您的代码失败,因为event对象用{'Date': 'Feb 22'}填充,但是您的代码期望的远远超过此。因此,当您尝试通过尝试访问currentIntent来解析此JSON时,它将失败:

date_input = event['currentIntent']['slots']['Date']

从控制台进行测试时,您无法将任何context传递给Lambda,因为它是由AWS自动填充的。另外,上下文仅在非常特定的情况下使用,因此我现在不必担心。

但是,您可以将event作为参数传递,并且有很多方法可以使用。手动执行此操作最简单的方法是转到AWS的Lambda控制台,单击“测试”,如果尚未配置任何“测试事件”,则会弹出以下屏幕

enter image description here

现在,您可以在下拉菜单中选择您的事件,AWS将为您填写事件,如下所示:

enter image description here

您现在可以按照自己的方式自定义事件。

保存并单击“测试”后,event对象将使用提供的JSON填充。

另一种选择是检查Sample Events Published By Event Sources,这样您就可以简单地捕获想要的任何JSON事件并相应地对其进行定制。

我为您获取了Lex Sample Event,它看起来像这样:

{
  "messageVersion": "1.0",
  "invocationSource": "FulfillmentCodeHook or DialogCodeHook",
  "userId": "user-id specified in the POST request to Amazon Lex.",
  "sessionAttributes": { 
     "key1": "value1",
     "key2": "value2",
  },
  "bot": {
    "name": "bot-name",
    "alias": "bot-alias",
    "version": "bot-version"
  },
  "outputDialogMode": "Text or Voice, based on ContentType request header in runtime API request",
  "currentIntent": {
    "name": "intent-name",
    "slots": {
      "slot-name": "value",
      "slot-name": "value",
      "slot-name": "value"
    },
    "confirmationStatus": "None, Confirmed, or Denied
      (intent confirmation, if configured)"
  }
}

将其用作您的活动,就可以相应地对其进行测试。