Question

我正在AWS IoT上为两个MCU传感器设置SNS推送通知。

现在，当湿度较低时，我会收到警报，因此我想包含温度/湿度数据，但是它给我的值是none或抛出错误无效的JSON。我该如何解决？

工作代码：

def myShadowUpdateCallback(payload, responseStatus, token):
  print()
  print('UPDATE: $aws/things/' + SHADOW_HANDLER +
    '/shadow/update/#')
  print("payload = " + payload)
  print("responseStatus = " + responseStatus)
  print("token = " + token)

channel = 21
GPIO.setup(channel, GPIO.IN)

while True:

  if GPIO.input(channel):
    myDeviceShadow.shadowUpdate(
      '{"state":{"reported":{"moisture":"low"}}}',
      myShadowUpdateCallback, 5)
  else:
    myDeviceShadow.shadowUpdate(
      '{"state":{"reported":{"moisture":"okay"}}}',
      myShadowUpdateCallback, 5)

电子邮件结果：

{"state":{"reported":{"moisture":"low"}},"metadata":{"reported":{"moisture":{"timestamp":1548870624}}},"version":5167,"timestamp":1548870624,"clientToken":"b8a2"}

为使DH22温度/湿度传感器正常工作，我添加了：

import Adafruit_DHT

humidity, temperature = Adafruit_DHT.read_retry(Adafruit_DHT.DHT22, 20)

已更改：

def myShadowUpdateCallback(payload, responseStatus, token):
  print()
  print('UPDATE: $aws/things/' + SHADOW_HANDLER +
    '/shadow/update/#')
  print("payload = " + payload)
  print("responseStatus = " + responseStatus)
  print("token = " + token)
  print('Temperature={}*F  Humidity={}%'.format(temperature, humidity))

while True:

  if GPIO.input(channel):
    myDeviceShadow.shadowUpdate(
      '{"state":{"reported":{"moisture":"low","humidity":{"0":"0.1f"},"temperature":{"1":"0.1f"}}}}',
      myShadowUpdateCallback, 5)
  else:
    myDeviceShadow.shadowUpdate(
      '{"state":{"reported":{"moisture":"okay","humidity":{"0":"0.1f"},"temperature":{"1":"0.1f"}}}}',
      myShadowUpdateCallback, 5)

错误：

当湿度正常时，温度和湿度显示：

Temperature=None*F  Humidity=None%

当湿度低时，我会得到一个错误：

myShadowUpdateCallback, ValueError: Invalid JSON file.

Answer 1

看起来{0：0.1f}部分不是有效的json。也许将其更改为{“ 0”：“ 0.1f”}或其他有效的json。

None或ValueError（“无效的JSON文件。”）的值

1 个答案: