在django中使用apscheduler 执行计划任务的实现方法

virtualenv env
. env/bin/activate

pip install apscheduler django psycopg2 requests
II. Build your app
Create a new Django project:

django-admin.py startproject advancedScheduler
cd advancedScheduler
python manage.py startapp weather

[ super_project_directory/ ]
|
+----[ env/ ] <-- Virtualenv stuff
|
+----[ advancedScheduler/ ] <-- the Root Directory
 |
 +----[ advancedScheduler/ ] <-- the Django Project Directory
 |
 +----[ weather/ ] <-- the Django App Directory

INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'weather'
]

from django.conf.urls import url
from weather import views
urlpatterns = [
 url(r'^$', views.MainPage.as_view())
]

from django.db import models
from datetime import datetime 
 
class Forecast(models.Model):
 timestamp = models.DateTimeField()
 temperatue = models.DecimalField(max_digits=12,decimal_places=2)
 description = models.CharField(max_length=150)
 city = models.CharField(max_length=150)
 
 def save(self, *args, **kwargs):
 if not self.id:
  self.timestamp = datetime.utcnow()
 return super(Forecast, self).save(*args, **kwargs)
Template
<div style="text-align: center">
 <h5>Currently in</h5>
 <h3>{{city}}</h3>
 <h4>{{temperature_in_f}} F | {{temperature_in_c}} C</h4>
 <h4>{{desctiprion}}</h4>
 <p><em>Last updated {{utc_update_time}} GMT</em></p>
</div>
View
import decimal
from datetime import datetime 
from django.shortcuts import render
from django.views.generic import TemplateView
from weather.models import Forecast 
class MainPage(TemplateView):
 def get(self, request, **kwargs):
 
 latest_forecast = Forecast.objects.latest('timestamp')
 city = latest_forecast.city
 temperature_in_c = latest_forecast.temperatue
 temperature_in_f = (latest_forecast.temperatue * decimal.Decimal(1.8)) + 32
 description = latest_forecast.description.capitalize
 timestamp = "{t.year}/{t.month:02d}/{t.day:02d} - {t.hour:02d}:{t.minute:02d}:{t.second:02d}".format( t=latest_forecast.timestamp)
 return render(
  request, 
  'index.html', 
  {
  'city':city,
  'temperature_in_c': temperature_in_c,
  'temperature_in_f': round(temperature_in_f,2),
  'desctiprion': description,
  'utc_update_time': timestamp})

DATABASES = {
 'default': {
 'ENGINE': 'django.db.backends.postgresql_psycopg2',
 'NAME': 'advancedScheduler',
 'USER': 'some_user_name',
 'PASSWORD': 'some_password',
 'HOST': 'localhost',
 'PORT': '',
 }
}

python manage.py makemigrations
python manage.py migrate

[ super_project_directory/ ]
|
+----[ env/ ]
|
+----[ advancedScheduler/ ] <-- the Root Directory
 |
 +----[ advancedScheduler/ ] 
 |
 +----[ weather/ ] 
 |
 +----[ forecastUpdater/ ] <-- the new Updater Module
  |
  +----< __init__.py > <--+
  |    |-- two new Python files
  +----< forecastApi.py > <--+
import requests
from weather.models import Forecast
 
def _get_forecast_json():
 url = 'http://api.openweathermap.org/data/2.5/weather'
 encoded_city_name = 'Los%20Angeles'
 country_code = 'us'
 access_token = 'your_access_token'
 
 r = requests.get('{0}?q={1},{2}&APPID={3}'.format(
 url, 
 encoded_city_name, 
 country_code, 
 access_token))
 
 try:
 r.raise_for_status()
 return r.json()
 except:
 return None
 
 
def update_forecast():
 json = _get_forecast_json()
 if json is not None:
 try:
  new_forecast = Forecast()
  
  # open weather map gives temps in Kelvin. We want celsius.  
  temp_in_celsius = json['main']['temp'] - 273.15
  new_forecast.temperatue = temp_in_celsius
  new_forecast.description = json['weather'][0]['description']
  new_forecast.city = json['name']
  new_forecast.save()
  print("saving...\n" + new_forecast)
 except:
  pass

from datetime import datetime
from apscheduler.schedulers.background import BackgroundScheduler
from forecastUpdater import forecastApi
 
def start():
 scheduler = BackgroundScheduler()
 scheduler.add_job(forecastApi.update_forecast, 'interval', minutes=5)
 scheduler.start()

class WeatherConfig(AppConfig):
 name = 'weather'

from django.apps import AppConfig
class WeatherConfig(AppConfig):
 name = 'weather'
 def ready(self):
 from forecastUpdater import updater
 updater.start()

INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'weather.apps.WeatherConfig' 
]