In this latest update we have now enabled change indicators for status events and updates.
What are change indicators?
Change indicators are supplementary data fields that allow you to see which data fields have changed from the previous update. For example, if the previous estimated time of departure was 0800, and the latest update that was just received was 0815, change indicators would tell you that there was a change in the estimated time of departure, and what the previous value (0800) was. These indicators will be provided for every data field which is expected to receive changes.
Please note that change indicators are currently only available for status changes. Schedule change indicators are not yet available and will be released at a later date.
Change Indicators JSON
Here is an exhaustive example of change indicators in the JSON:
"changes": [
{
"propertyName": "State"
},
{
"propertyName": "Equipment.AircraftType.Iata"
},
{
"propertyName": "Equipment.AircraftType.Icao"
},
{
"propertyName": "Equipment.AircraftRegistrationNumber"
},
{
"propertyName": "Departure.Times.Estimated.OutGateTimeliness"
},
{
"propertyName": "Departure.Times.Estimated.OutGateVariation"
},
{
"propertyName": "Departure.Times.Estimated.OutGate.Local"
},
{
"propertyName": "Departure.Times.Estimated.OutGate.UTC"
},
{
"propertyName": "Departure.Times.Actual.OutGateTimeliness"
},
{
"propertyName": "Departure.Times.Actual.OutGateVariation"
},
{
"propertyName": "Departure.Times.Actual.OutGate.Local"
},
{
"propertyName": "Departure.Times.Actual.OutGate.UTC"
},
{
"propertyName": "Departure.Times.Actual.OffGround.Local"
},
{
"propertyName": "Departure.Times.Actual.OffGround.UTC"
},
{
"propertyName": "Departure.Terminal"
},
{
"propertyName": "Departure.Gate"
},
{
"propertyName": "Arrival.Times.Estimated.OnGround.Local"
},
{
"propertyName": "Arrival.Times.Estimated.OnGround.UTC"
},
{
"propertyName": "Arrival.Times.Estimated.InGateTimeliness"
},
{
"propertyName": "Arrival.Times.Estimated.InGateVariation"
},
{
"propertyName": "Arrival.Times.Estimated.InGate.Local"
},
{
"propertyName": "Arrival.Times.Estimated.InGate.UTC"
},
{
"propertyName": "Arrival.Times.Actual.OnGround.Local"
},
{
"propertyName": "Arrival.Times.Actual.OnGround.UTC"
},
{
"propertyName": "Arrival.Times.Actual.InGateTimeliness"
},
{
"propertyName": "Arrival.Times.Actual.InGateVariation"
},
{
"propertyName": "Arrival.Times.Actual.InGate.Local"
},
{
"propertyName": "Arrival.Times.Actual.InGate.UTC"
},
{
"propertyName": "Arrival.Baggage"
},
{
"propertyName": "Arrival.Terminal"
},
{
"propertyName": "Arrival.Gate"
}
{
"propertyName": "Equipment.Seats.FirstClass"
},
{
"propertyName": "Equipment.Seats.BusinessClass"
},
{
"propertyName": "Equipment.Seats.PremiumEconomyClass"
},
{
"propertyName": "Equipment.Seats.EconomyPlusClass"
},
{
"propertyName": "Equipment.Seats.EconomyClass"
},
{
"propertyName": "Equipment.Seats.TotalSeats"
}
],
Fields that are not present in the change indicators are fields that are not expected to change, technical information (metadata) or are tied to the schedule e.g. origination departure date, carrier code, flight number etc.
Each change indicator may also come with an accompanying data field called "previousValue", which indicates what the previous value in the previous flight update was. Here is a simple example:
"changes": [
{
"propertyName": "Departure.Terminal",
"previousValue": "D"
},
{
"propertyName": "Departure.Gate",
"previousValue": "D36"
}
],
In the example above, the previous value of both the departure terminal and gate are indicated. For flight updates that did not have a previous value i.e. the value was null or empty in the previous update, only the propertyName field would appear.
How do I enable Change Indicators?
Change indicators can be enabled for status alerts just by adding this additional parameter:
"changeIndicator": true
To your alert when creating or updating the alert. Please note that change indicators are not active for schedule alerts at the moment.
If you have an alert that covers both schedules and status, change indicators will only be sent in the status updates.