Help Center/ IoT Device Access/ API Reference/ MQTT or MQTTS API Reference on the Device Side/ Device Time Synchronization/ Device Requesting Time Synchronization
Updated on 2024-12-02 GMT+08:00
View PDF
Share

Device Requesting Time Synchronization

Function

This API is used by a device to send a request for synchronizing time with the platform.

Topic

Upstream: $oc/devices/{device_id}/sys/events/up

Parameters

Parameter

Mandatory/Optional

Type

Description

object_device_id

Optional

String

Explanation:

  • Mandatory when the child device reports data during the gateway device data reporting. Specify object_device_id as the child device ID of the device in the topic. Otherwise, the request fails.
  • When a directly connected device reports data, the value of object_device_id must be the same as that of device_id in the topic.
  • If this parameter is left blank, the value of this parameter is the same as that of device_id in the topic by default.

services

Optional

List<ServiceEvent>

Explanation:

List of services that an event is about.

ServiceEvent structure

Parameter

Mandatory/Optional

Type

Description

service_id

Mandatory

String

Explanation:

System field.

Value range:

Fixed at $time_sync.

event_type

Mandatory

String

Explanation:

System field.

Value range:

Fixed at time_sync_request.

event_time

Optional

String

Explanation:

Event time. UTC time format: yyyyMMdd'T'HHmmss'Z'.

If this parameter is not carried in the reported data or is in incorrect format, the time when the platform receives the data is used.

paras

Mandatory

Object

Explanation:

Event parameters in JSON format.

paras structure

Parameter

Mandatory/Optional

Type

Description

device_send_time

Mandatory

long

Explanation:

Timestamp when the device sends the request. The timestamp is the number of milliseconds since 00:00:00 on January 1, 1970 in Greenwich Mean Time (GMT).

Example

Topic: $oc/devices/{device_id}/sys/events/up  
Data format:
{ 
    "object_device_id": "{object_device_id}", 
    "services": [{ 
        "service_id": "$time_sync", 
        "event_type": "time_sync_request", 
        "event_time": "20151212T121212Z",
         "paras": { 
            "device_send_time": 1582685678789
         } 
    }] 
}