python中的KeyError GAE使用cron推送任务队列 [英] KeyError during python GAE push task queue with cron

问题描述

我很接近完成一个使用GAE中的推送任务队列向用户发送后续电子邮件的项目。但是，我不断得到一个KeyError，不知道为什么。我一直在寻找好的模型，以我的项目为基础，但没有找到任何使用多个参数的体面的例子。 GAE文档在上个月有所改进，但仍有很多需要。

I'm very close to finishing up a project that uses push task queues in GAE to send out follow-up emails to users. However, I keep getting a KeyError and don't know why. I been looking for good models to base my project on but haven't found any decent examples that use multiple parameters. The GAE documentation has improved in the last month but still leaves a lot to be desired.

我在开发服务器中使用交互式控制台检查了很多代码但仍然我不知道我做错了什么。我最好的猜测是，参数不会传递到脚本的下一部分（类pushQueue）。

I've checked many pieces of the code using the interactive console in the development server but still I don't know what I am doing wrong. My best guess is that the parameters are not getting passed along to the next part of the script (class pushQueue).

app.yaml：

application: gae-project
version: 1
runtime: python27
api_version: 1
threadsafe: true

handlers:
- url: /cron/sendfu
  script: main.app
  login: admin

- url: /emailworker
  script: main.app
  login: admin

- url: /worker
  script: main.app
  login: admin

- url: /.*
  script: main.app
  login: required

cron.yaml：

cron:
- description: sends follow-up emails
  url: /cron/sendfu
  schedule: every day 20:00

queue.yaml：

total_storage_limit: 120M
queue:
- name: emailworker
  rate: 1/s
  bucket_size: 50
  retry_parameters:
    task_retry_limit: 5
    task_age_limit: 6h
    min_backoff_seconds: 10
    max_backoff_seconds: 60

main.py： strong>

main.py:

import webapp2
import datetime
from google.appengine.ext import db
from google.appengine.api import users
from google.appengine.api import taskqueue
import jinja2
import os

jinja_environment = jinja2.Environment(
loader=jinja2.FileSystemLoader(os.path.dirname(__file__)))

class emailJobs(db.Model):
    """ Models an a list of email jobs for each user """
    triggerid = db.StringProperty()  #Trig id
    recipientid_po = db.StringProperty() # id
    recipientlang = db.StringProperty()  #Language
    fu_email_sent = db.DateTimeProperty() 
    fuperiod = db.IntegerProperty() # (0 - 13)
    fu1 = db.DateTimeProperty() 
    fu2 = db.DateTimeProperty()

    @classmethod
    def update_fusent(cls, key_name, senddate):
        """ Class method that updates fu messages sent in the GAE Datastore """
        emailsjobs = cls.get_by_key_name(key_name)
        if emailsjobs is None:
            emailsjobs = cls(key_name=key_name)
        emailsjobs.fu_email_sent = senddate
        emailsjobs.put()

def timeStampFM(now):
    d = now.date()
    year = d.year
    month = d.month
    day = d.day
    t = now.time()
    hour = t.hour
    minute = t.minute + 5
    second = t.second
    today_datetime = datetime.datetime(year, month, day, hour, minute, second)
    return today_datetime


class MainPage(webapp2.RequestHandler):
    """ Main admin login page """
    def get(self):
        if users.get_current_user():
            url = users.create_logout_url(self.request.uri)
            url_linktext = 'Logout'
            urla = '/'
            url_admin = ""
            if users.is_current_user_admin():
                url = users.create_logout_url(self.request.uri)
                urla = "_ah/admin/"
                url_admin = 'Go to admin pages'
                url_linktext = 'Logout'

        else:
            url = users.create_login_url(self.request.uri)
            url_linktext = 'Login'

        template_values = {
            'url': url,
            'url_linktext': url_linktext,
            'url_admin': url_admin,
            'urla': urla,
            }

        template = jinja_environment.get_template('index.html')
        self.response.out.write(template.render(template_values))


class sendFollowUp(webapp2.RequestHandler):
    """ Queries Datastore for fu dates that match today's date, then adds them to a task queue """
    def get(self):

        now = datetime.datetime.now()
        now_dt = now.date() #today's date to compare with fu dates

        q = emailJobs.all()
        q.filter('fuperiod >', 0)
        q.filter('fuperiod <', 99)

        for part in q:
            guid = str(part.recipientid_po)
            lang = str(part.recipientlang)
            trigid = str(part.triggerid)

            if part.fuperiod == 1:
                fu1rawdt = part.fu1
                fu1dt = fu1rawdt.date()
                if fu1dt == now_dt:
                    follow_up = '1'

            if part.fuperiod == 2:
                fu2rawdt = part.fu2
                fu2dt = fu2rawdt.date()
                if fu2dt == now_dt:
                    follow_up = '2'

            if follow_up != None:
                taskqueue.add(queue_name='emailworker', url='/emailworker', params={'guid': guid,
                                                                                'fu': follow_up,
                                                                                'lang': lang,
                                                                                'trigid': trigid,
                                                                                })
        self.redirect('/emailworker')


class pushQueue(webapp2.RequestHandler):
    """ Sends fu emails, updates the Datastore with datetime sent """

    def store_emails(self, trigid, senddate):
        db.run_in_transaction(emailJobs.update_fusent, trigid, senddate)

    def get(self):
        fu_messages = {'1': 'MS_x01', 
                       '2': 'MS_x02',
                       }
        langs = {'EN': 'English subject',
                 'ES': 'Spanish subject',
                 }

        fu = str(self.request.get('fu'))
        messageid = fu_messages[fu]

        lang = str(self.request.get('lang'))
        subject = langs[lang]

        now = datetime.datetime.now()
        senddate = timeStampFM(now)

        guid = str(self.request.get('guid'))
        trigid = str(self.request.get('trigid'))

        data = {}
        data['Subject'] = subject
        data['MessageID'] = messageid
        data['SendDate'] = senddate
        data['RecipientID'] = guid
        # Here I do something with data = {}

        self.store_emails(trigid, senddate)

app = webapp2.WSGIApplication([('/', MainPage),
                           ('/cron/sendfu', sendFollowUp),
                           ('/emailworker', pushQueue)],
                           debug=True)

当我测试cron工作在：localhost：8086 / cron / sendfu

When I test the cron job at: localhost:8086/cron/sendfu

它重定向到：localhost：8086 / emailworker

It redirects to: localhost:8086/emailworker

并收到以下错误消息：

Traceback (most recent call last):
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1535, in __call__
rv = self.handle_exception(request, response, e)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1529, in __call__
rv = self.router.dispatch(request, response)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1278, in default_dispatcher
return route.handler_adapter(request, response)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1102, in __call__
return handler.dispatch()
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 572, in dispatch
return self.handle_exception(e, self.app.debug)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 570, in dispatch
return method(*args, **kwargs)
  File "/Users/me/Documents/workspace/gae-project/src/main.py", line 478, in get
messageid = fu_messages[fu]
KeyError: ''

INFO     2013-03-05 03:03:22,337 dev_appserver.py:3104] "GET /cron/sendfu HTTP/1.1" 302 -
ERROR    2013-03-05 03:03:22,348 webapp2.py:1552] ''
Traceback (most recent call last):
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1535, in __call__
rv = self.handle_exception(request, response, e)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1529, in __call__
rv = self.router.dispatch(request, response)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1278, in default_dispatcher
return route.handler_adapter(request, response)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 1102, in __call__
return handler.dispatch()
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 572, in dispatch
return self.handle_exception(e, self.app.debug)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/lib/webapp2-2.5.2/webapp2.py", line 570, in dispatch
return method(*args, **kwargs)
  File "/Users/me/Documents/workspace/gae-project/src/main.py", line 478, in get
messageid = fu_messages[fu]
KeyError: ''
INFO     2013-03-05 03:03:22,355 dev_appserver.py:3104] "GET /emailworker HTTP/1.1" 500 -
INFO     2013-03-05 03:03:22,509 dev_appserver.py:3104] "GET /favicon.ico HTTP/1.1" 404 -

lines：

469    def get(self):
470        fu_messages = {'1': 'MS_x01', 
471                       '2': 'MS_x02',
472                       }
473        langs = {'EN': 'English subject',
474                 'ES': 'Spanish subject',
475                 }
476
477        fu = str(self.request.get('fu'))
478        messageid = fu_messages[fu]

推荐答案

当您致电

fu = str(self.request.get('fu'))

b $ b

如果请求中没有'fu'，则 self.request.get 空字符串（''）。因此，当您尝试

if there is no 'fu' in the request, self.request.get will return the empty string (''). So when you try

messageid = fu_messages[fu]

它查找

fu_messages = {'1': 'MS_x01', 
               '2': 'MS_x02',
               }

只有'1'和'2'作为键。

您的 pushQueue 处理程序没有看到您通过

The reason your pushQueue handler is not seeing the params you send via

params = {
    'guid': guid,
    'fu': follow_up,
    'lang': lang,
    'trigid': trigid,
}
taskqueue.add(queue_name='emailworker', url='/emailworker', 
              params=params)

是因为您使用 GET 处理程序而不是< c $ c> POST 或 PUT 处理程序。由于文档说明：

is because you are using a GET handler instead of a POST or PUT handler. As the documentation states:

参数编码为 application / x-www-form-urlencoded ，并设置为
。 p>

Params are encoded as application/x-www-form-urlencoded and set to the payload.

因此，请求的有效载荷中有'fu' param因为它是一个 GET 请求，有效载荷被丢弃（这是HTTP的工作原理，而不是专用于App Engine）。如果您使用 POST 作为处理程序，则有效负载将按预期方式传递。

So the payload of the request has your 'fu' param in it, but since it is a GET request, the payload is dropped (this is how HTTP works, not specific to App Engine). If you use POST as your handler, the payload will come through as expected.

我注意到您的代码非常类似于记录的示例，但仅使用 get 其中示例使用 post 。

I noticed your code is very similar to the documented sample, but simply uses get where the sample uses post.

这篇关于python中的KeyError GAE使用cron推送任务队列的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！