尝试将事件发送到 Alexa 事件网关时 JSON 格式错误

Question

我正在尝试为运动传感器制作 Alexa Skill。我需要将 Alexa.ChangeReport 事件发送到 Alexa 事件网关，但我不断收到格式错误的 JSON 错误。

我在MotionSensor Interface Documentation中使用了亚马逊为他们的ChangeReport提供的完全相同的事件格式，但他们仍然说格式错误的JSON。首先，我还没有编写代码来刷新和获取更新的令牌，而只是确保我的令牌有效。有什么想法吗？

这是我的代码：

motion_state=get_motion_state_from_iot()
    acc_token = payload['state']['desired']['LWA_Access_Token']
    message_id = str(uuid.uuid4())
    current_time = datetime.datetime.utcnow().isoformat() + "Z"

    event_data = urllib.parse.urlencode(
    {  
      "event": {
        "header": {
          "namespace": "Alexa",
          "name": "ChangeReport",
          "messageId": message_id,
          "payloadVersion": "3"
        },
        "endpoint": {
          "scope": {
            "type": "BearerToken",
            "token": acc_token
          },
          "endpointId": endpoint_id
        },
        "payload": {
          "change": {
            "cause": {
              "type": "PHYSICAL_INTERACTION"
            },
            "properties": [
              {
                "namespace": "Alexa.MotionSensor",
                "name": "detectionState",
                "value": motion_state,
                "timeOfSample": current_time,
                "uncertaintyInMilliseconds": 0
              }
            ]
          }
        }
      },
      "context": {
        "properties": [
          {
            "namespace": "Alexa.EndpointHealth",
            "name": "connectivity",
            "value": {
              "value": "OK"
            },
            "timeOfSample": current_time,
            "uncertaintyInMilliseconds": 0
          }
        ]
      }
    }
    ).encode("utf-8")
    
    url = "https://api.eu.amazonalexa.com/v3/events"
    
    headers = {
        'Authorization': f'Bearer {acc_token}',
        'Content-Type': 'application/json'
    }
    
    posting = urllib.request.Request(url, event_data, headers, "POST")

    try:
        with urllib.request.urlopen(posting) as response:
            lwa_tokens = json.loads(response.read().decode("utf-8"))
            return ("Success!")
            
    except HTTPError as http_error:
        return(f"An error occurred: {http_error.read().decode('utf-8')}")

这是解码的错误

"An error occurred: {\"header\":{\"namespace\":\"System\",\"name\":\"Exception\",\"messageId\":\"01ca3509-734d-49ba-a89c-40cf93e2c0ae\"},\"payload\":{\"code\":\"INVALID_REQUEST_EXCEPTION\",\"description\":\"The request was malformed.\"}}"

Answer 1

您传递给

urllib.parse.urlencode()

的值不是有效的 Python 对象。查看此函数的文档并找出它需要什么作为输入。如果它是字符串，则需要使用 str.format() 或 f-string 语法将整个参数格式化为字符串来合并变量。