Callback notifications for resources and lifecycle events
- Operations on resources
- Life cycle events
- Observed resources
IMPACT IoT sends the requested information in the form of asynchronous notifications on the callback URL of the client application.
Callback notifications describes the structure of the callback notification API.
| Title | Callback notifications |
|---|---|
| URL | https://<netApp_callback_url> |
| Method | POST |
| Content-Type | application/json |
| URL Params | None |
| Data Params |
The following are the data parameters:
|
| Callback Response Status Code | The
following are the callback response status codes:
|
| Sample Call | Curl: |
| Notes | None |
Controlling the payload size
IMPACT IoT allows controlling the payload size for the Application callback notifications. The payload size is set at a system level and can be overridden by the Application at registration.
For controlling the payload size at the user level, the user can configure the payload
size at the time of registration using the registration API using the optional
payloadSize field, in Bytes.
For example:
PUT /m2m/applications/registration HTTP/1.1
Host: devlwm2m-edge-01
Authorization: Basic ZHRhZzpkdGFn
Content-Type: application/json
Content-Length: 153
{
"headers":
{"authorization": "Basic ZGVtbzpkZW1v"}
,
"url": "http://10.75.74.104:8503",
"payloadSize": 40000
}Oversized uplink payloads
In cases where the payload cannot be segmented, for example, due to a large single encrypted uplink packet, the application may receive a payload greater than the maximum payload size.
Precendence order
The payload size from the API (user level) will get precedence over the system level
limit. If the payloadSize is not provided for a user, IMPACT IoT will use the system level value for the user.
Sample for subscription failure
If an Application has requested a subscription which has failed for some reason, then this will be detailed to the Application. An example of this occurring is when an attempt to create a LWM2M observation fails.
Following is a sample subscription failure notification:
{"reports":[{"serialNumber":"ntc-obsfailure",
"timestamp":1696514848389,"subscriptionId":"beafdb2a-eb8d-4390-b1f9-3eac5ccd4553"
,"resourcePath":"10/0/20","customAttributes":{},"protocol":"LWM2M","errorMessage"
:"NOT_FOUND"}],"registrations":[],"deregistrations":[],"updates":[],"expirations"
:[],"responses":[]}