我正在GAE上运行每日报告任务,因为最近使用了太多内存来完成.因此,我想将其设置为后端任务.我将后端设置如下：

backends:
- name: reporting
  class: B4_1G
  options: dynamic
  start: reporting.app

在reporting.py中,定义了许多类,它们调用不同的报告.我的cron.yaml目前看起来像这样：

cron:
- description: update report 1
  url: /reports/report1
  schedule: every day 03:00
- description: update report 2
  url: /reports/report2
  schedule: every day 03:30

但从逻辑上讲,这只是通过app.yaml调用前端实例上的作业,目前看起来像这样：

application: appname
version: 1
runtime: python27
api_version: 1
threadsafe: true

handlers:
- url: /(robots\.txt)
  static_files: \1
  upload: (robots\.txt)
- url: /favicon\.ico
  static_files: favicon.ico
  upload: favicon\.ico
- url: /sitemap\.xml
  static_files: sitemap.xml
  upload: sitemap\.xml
- url: /images
  static_dir: images
- url: /js
  static_dir: js
- url: /css
  static_dir: css
- url: /reports/.*
  script: reporting.app
  login: admin

我必须每天更改为在后端实例上调用这些作业？

解决方法:

取决于您是否需要persistent or dynamic后端

对于动态的

计划是：

> A cron在特定时间开火.
>添加一个将启动后端的task on a queue
>后端开始

例：

app.yaml中：

- url: /crons/startgooglepluscrawler/
  script: crons.startgooglepluscrawler.app
  login: admin

backends.yaml：

backends: 
- name: google-plus-crawler
  class: B2
  start: backends.googlepluscrawler.app
  options: dynamic, failfast
  instances: 1

crons.yaml：

cron:
- description: get daily google plus user followers and followings
  url: /crons/startgooglepluscrawler/
  schedule: every day 09:00

queue.yaml中：

total_storage_limit: 10M
queue:
- name: google-plus-daily-crawling
  rate: 1/s
  retry_parameters:
    task_retry_limit: 0
    task_age_limit: 1s

在startgooglepluscrawler.app上,您需要使用taskqueue启动后端：

class StartGooglePlusCrawlerHandler(webapp2.RequestHandler):

    def get(self):
        logging.info("Running daily Cron")
        taskqueue.add(queue_name = "google-plus-daily-crawling",
                    url="/_ah/start",
                    method='GET',
                    target=(None if self.is_dev_server() else 'google-plus-crawler'),
                    headers={"X-AppEngine-FailFast":"true"}
                    )
        logging.info("Daily Cron finished")

    def is_dev_server(self):
        return os.environ['SERVER_SOFTWARE'].startswith('Dev')


app = webapp2.WSGIApplication([
        ("/crons/startgooglepluscrawler/",StartGooglePlusCrawlerHandler)

    ],debug=True)

在后端/ googlepluscrawler.py通常就像一个应用程序,以及/ _ah / start的处理程序：

app = webapp2.WSGIApplication(
            [('/_ah/start', StartHandler)],
            debug=True,
            config=config.config)

上面的示例将启动后端实例.