编写函数

编写函数代码

1. 登录函数计算控制台。
2. 在顶部菜单栏，选择地域。
3. 在左侧导航栏，单击服务及函数。
4. 在服务列表区域，单击目标服务。然后在函数列表页签，单击目标函数名称。
   
5. 单击代码执行页签，在代码编辑器中编写代码。

   本文以Python为例，示例代码如下。

   # -*- coding: utf-8 -*-
   import logging
   import json, random, string, time
   from aliyunsdkcore import client
   from aliyunsdkecs.request.v20140526.DeleteSnapshotRequest import DeleteSnapshotRequest
   from aliyunsdkecs.request.v20140526.CreateSnapshotRequest import CreateSnapshotRequest
   from aliyunsdkecs.request.v20140526.DescribeDisksRequest import DescribeDisksRequest
   from aliyunsdkcore.auth.credentials import StsTokenCredential
   
   LOGGER = logging.getLogger()
   clt = None
   
   def handler(event, context):
     creds = context.credentials
     sts_token_credential = StsTokenCredential(creds.access_key_id, creds.access_key_secret, creds.security_token)
     '''
     {
       "product": "ECS",
       "content": {
           "executeFinishTime": "2018-06-08T01:25:37Z",
           "executeStartTime": "2018-06-08T01:23:37Z",
           "ecsInstanceName": "timewarp",
           "eventId": "e-t4nhcpqcu8fqushpn3mm",
           "eventType": "InstanceFailure.Reboot",
           "ecsInstanceId": "i-bp18l0uopocfc98xxxx" 
       },
       "resourceId": "acs:ecs:cn-hangzhou:12345678:instance/i-bp18l0uopocfc98xxxx",
       "level": "CRITICAL",
       "instanceName": "instanceName",
       "status": "Executing",
       "name": "Instance:SystemFailure.Reboot:Executing", 
       "regionId": "cn-hangzhou"
     }
     '''
   
     evt = json.loads(event)
     content = evt.get("content");
     ecsInstanceId = content.get("ecsInstanceId");
     regionId = evt.get("regionId");
   
     global clt
     clt = client.AcsClient(region_id=regionId, credential=sts_token_credential)
     name = evt.get("name");
     name = name.lower()
   
     if name in [ 'Instance:SystemFailure.Reboot:Executing'.lower(), "Instance:InstanceFailure.Reboot:Executing".lower()]:
       pass
       # do other things
   
     if name in ['Instance:SystemFailure.Reboot:Executed'.lower(), "Instance:InstanceFailure.Reboot:Executed".lower()]:
       request = DescribeDisksRequest()
       request.add_query_param("RegionId", regionId)
       request.set_InstanceId(ecsInstanceId)
       response = _send_request(request)
       disks = response.get('Disks').get('Disk', [])
       for disk in disks:
         diskId = disk["DiskId"]
         SnapshotId = create_ecs_snap_by_id(diskId)
         LOGGER.info("Create ecs snap sucess, ecs id = %s , disk id = %s ", ecsInstanceId, diskId)
   
   def create_ecs_snap_by_id(disk_id):
       LOGGER.info("Create ecs snap, disk id is %s ", disk_id)
       request = CreateSnapshotRequest()
       request.set_DiskId(disk_id)
       request.set_SnapshotName("reboot_" + ''.join(random.choice(string.ascii_lowercase) for _ in range(6)))
       response = _send_request(request)
       return response.get("SnapshotId")
   
   # send open api request
   def _send_request(request):
       request.set_accept_format('json')
       try:
           response_str = clt.do_action_with_exception(request)
           LOGGER.info(response_str)
           response_detail = json.loads(response_str)
           return response_detail
       except Exception as e:
           LOGGER.error(e)