# Creating an AS Policy

#### Scenario

An AS policy specifies a condition for triggering a scaling action. When the trigger condition is met, a scaling action occurs.

#### Precautions

- If you use a token for authentication, you must call the IAM API to obtain the user's token and add X-Auth-Token to the request message header of ECS API you call.
- The validity period of the token obtained from the IAM service is 24 hours. If you want to use a token for authentication, you can cache it to avoid frequently calling the IAM API.

#### Involved APIs

- IAM API used to obtain the token
- API used to query AS groups
- API used to create an AS policy

#### Procedure

1. For details about token authentication, see Token Authentication.
2. Send GET https://AS endpoint/autoscaling-api/v1/{tenant_id}/scaling_group to obtain AS groups. Use the ID of one of the AS groups as parameter scaling_group_id for creating an AS policy. For the response parameters of the API used to query AS groups, see section Response Parameters for Querying AS Groups.
3. Send POST https://AS endpoint/autoscaling-api/v1/{tenant_id}/scaling_policy to create an AS policy, such as a periodic policy which is executed on Sunday, Tuesday, and Thursday. For detailed parameters, see section "Creating an AS Policy" in the Auto Scaling API Reference.
   Specify the following parameters in the request body:

       {
           "scaling_policy_name": "as-policy-test",
           "scaling_policy_action": {
               "operation": "ADD",
               "instance_number": 1
           },
           "cool_down_time": 900,
           "scheduled_policy": {
               "launch_time": "16:00",
               "recurrence_type": "Weekly",
               "recurrence_value": "1,3,5",
               "start_time": "2018-05-04T03:34Z",
               "end_time": "2018-12-27T03:34Z"
           },
           "scaling_policy_type": "RECURRENCE",
           "scaling_group_id": "5bc3aa02-b83e-454c-aba1-4d2095c68f8b"
       }

   scaling_policy_id is returned if the request is successful.

Parent topic: Common Operations