Question

import datetime
from threading import Timer
import firebase_admin
from firebase_admin import firestore
import calendar

db = firestore.Client()
col_ref = db.collection(u'tblAssgin').get()
current_serving = [doc.id for doc in col_ref]
#print(current_serving)

def sit_time():

    for i in current_serving:
        try:
            doc_ref = db.collection(u'tblAssgin').document(i)
        except:
            current_serving.remove(doc_ref)
        else:
            doc = doc_ref.get()
            a = doc.get('assginTime')
            assign_time = datetime.datetime.fromtimestamp(calendar.timegm(a.timetuple()))
            now = datetime.datetime.now()
            sitting_time = now - assign_time
            hours,remainder = divmod(sitting_time.seconds, 3600)
            minutes, seconds = divmod(remainder, 60)
            print('minutes:',minutes)
            updates = {u'sitting_time':minutes}
            doc_ref.update(updates)

t = None

def refresh():
    global t
    sit_time()
    t = Timer(60, refresh)
    t.daemon = True
    t.start()

refresh()

所以基本上上面的代码确实它首先获取集合名称'tblAssgin'的所有文档id并将其存储在'current_serving'列表中。然后，循环遍历每个文档并计算时间并在每60秒后再次运行。现在假设我删除了一个文档，然后找不到该文档。因此，我想在未找到文档时执行此操作，引发异常，并从“current_serving”列表中删除该文档ID。但是没有抓住这个例外。

请帮忙

提前致谢.. !!

Answer 1

如果文档不存在，您假设CollectionReference.document()会抛出异常。它没有。

>>> client.collection('non-existing').document('also-non-existing')
<google.cloud.firestore_v1beta1.document.DocumentReference object at 0x10feac208>

但如果文档不存在，DocumentReference.get()将抛出异常。

>>> client.collection('non-existing').document('also-non-existing').get()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "~/gae/lib/python3.6/site-packages/google/cloud/firestore_v1beta1/document.py", line 432, in get
    raise exceptions.NotFound(self._document_path)
google.api_core.exceptions.NotFound: 404 ~/databases/(default)/documents/non-existing/also-non-existing

除了阻止之外没有捕获的云Firestore异常

1 个答案: