The basic structure of an event has a few mandatory (source, type, time) fields. In addition there a some predefined fragments which are supported by the platform ootb. See the example below. There we have a location update which is interpreted by the platfrom using the c8y_Postition fragment.
{
"source": {
"id":"2284329" },
"type": "c8y_LocationUpdate",
"text": "Location Update",
"time": "{{current_C8Y_time}}",
"c8y_Position": {
"alt": 67,
"lng": 10,594389,
"lat": 50,80473
}
}
Your can easily add your own fragment to that or create a complete new Event Type.
{
"source": {
"id":"2284329" },
"type": "c8y_MyStringEvent",
"text": "MyString",
"time": "{{current_C8Y_time}}",
"myString": "This is my string"
}
Hope that helps!