python - 没有 Web 服务的 Bigquery cron 作业

Question

是否可以在不运行 Google App Engine Web 服务的情况下运行处理用户数据的脚本？

对于较小的脚本，效果很好，但是当我的脚本持续大约 40 分钟时，我收到错误:DeadlineExceededError

我的临时修复是在 Windows VM 上使用 Windows 调度程序以及带有 python 脚本的命令行

编辑:添加代码

jobs = []
jobs_status = []
jobs_error = []
# The project id whose datasets you'd like to list
PROJECT_NUMBER = 'project'
scope = ('https://www.googleapis.com/auth/bigquery',
         'https://www.googleapis.com/auth/cloud-platform',
         'https://www.googleapis.com/auth/drive',
         'https://spreadsheets.google.com/feeds')

credentials = ServiceAccountCredentials.from_json_keyfile_name('client_secrets.json', scope)

# Create the bigquery api client
service = googleapiclient.discovery.build('bigquery', 'v2', credentials=credentials)

def load_logs(source):
    body = {"rows": [
        {"json": source}
    ]}

    response = service.tabledata().insertAll(
        projectId=PROJECT_NUMBER,
        datasetId='test',
        tableId='test_log',
        body=body).execute()
    return response

def job_status():
    for job in jobs:
        _jobId = job['jobReference']['jobId']
        status = service.jobs().get(projectId=PROJECT_NUMBER, jobId=_jobId).execute()
        jobs_status.append(status['status']['state'])
        if 'errors' in status['status'].keys():
            query = str(status['configuration']['query']['query'])
            message = str(status['status']['errorResult']['message'])
            jobs_error.append({"query": query, "message": message})
    return jobs_status


def check_statues():
    while True:
        if all('DONE' in job for job in job_status()):
            return


def insert(query, tableid, disposition):
    job_body = {
     "configuration": {
      "query": {
       "query": query,
       "useLegacySql": True,
       "destinationTable": {
        "datasetId": "test",
        "projectId": "project",
        "tableId": tableid
       },
       "writeDisposition": disposition
      }
     }
    }

    r = service.jobs().insert(
        projectId=PROJECT_NUMBER,
        body=job_body).execute()
    jobs.append(r)
    return r



class MainPage(webapp2.RequestHandler):
    def get(self):
        query = "SELECT * FROM [gdocs_users.user_empty]"
        insert(query, 'users_data_p1', "WRITE_TRUNCATE")
        check_statues()
        query = "SELECT * FROM [gdocs_users.user_empty]"
        insert(query, 'users_data_p2', "WRITE_TRUNCATE")
        query = "SELECT * FROM [gdocs_users.user_%s]"
        for i in range(1, 1000):
            if i <= 600:
                insert(query % str(i).zfill(4), 'users_data_p1', "WRITE_APPEND")
            else:
                insert(query % str(i).zfill(4), 'user_data_p2', "WRITE_APPEND")
        for error in jobs_error:
            load_logs(error)


app = webapp2.WSGIApplication([
    ('/', MainPage),
], debug=True)

Answer 1

默认情况下，App Engine 服务使用 automatic scaling ，它对 HTTP 请求有 60 秒的限制，对任务队列请求有 10 分钟的限制。如果您将服务更改为使用基本或手动扩展，则您的任务队列请求最多可以运行 24 小时。

听起来您可能只需要一个实例来完成这项工作，因此也许创建第二个 service除了默认服务之外。在子文件夹中创建一个 bqservice 文件夹，其中包含以下 app.yaml 设置，这些设置使用最多一个实例的基本缩放:

# bqsservice/app.yaml
# Possibly use a separate service for your BQ code than
# the rest of your app:
service: bqservice
runtime: python27
api_version: 1
# Keep low memory/cost B1 class?
instance_class: B1
# Limit max services to 1 to keep costs down. There is an
# 8 instance hour limit to the free tier. This option still
# scales to 0 when not in use.
basic_scaling:
  max_instances: 1

# Handlers:
handlers:
- url: /.*
  script: main.app

然后创建一个 cron.yaml在同一服务中安排脚本运行。通过上面的示例配置，您可以将 BigQuery 逻辑放入 main.py 文件中，并在其中定义 WSGI 应用程序:

# bqservice/main.py
import webapp2

class CronHandler(webapp2.RequestHandler):

    def post(self):
       # Handle your cron work
       # ....

app = webapp2.WSGIApplication([
    #('/', MainPage),  # If you needed other handlers
    ('/mycron', CronHandler),
], debug=True)

如果您不打算将 App Engine 应用程序用于其他用途，则可以将这一切都纳入默认服务中。如果除了默认服务之外还执行此操作，则需要首先将某些内容部署到默认服务，即使它只是一个带有静态文件的简单 app.yaml。