Access Custompropertie set by Office.js from EWS - outlook

Question

I have made a Outlook Addin Angular8 Application using Office.js to interact with Outlook.
Everything works fine, the Addin works fine and stores a CustomPropertie to the Mailitem which can be read after reopening the Mailitem.
In this Implementation this is a simple hashmap.
this.customPropertiesContainer.set('lvAppointmentServiceId', this.selfiId);
this.customPropertiesContainer.saveAsync();
Now I want to read the Propertie in another Application using EWS to get the Mail Item.
Here the Implementation is very complex.
private PropertySet getPropertySetKnown() {
PropertySet propertySet = null;
try {
propertySet = new PropertySet(BasePropertySet.FirstClassProperties, getExtendedPropertyDefinition());
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
return propertySet;
}
private ExtendedPropertyDefinition getExtendedPropertyDefinition() throws Exception {
ExtendedPropertyDefinition extendedPropertyDefinition = new ExtendedPropertyDefinition(
DefaultExtendedPropertySet.PublicStrings, CATERING_JIRA_ID, MapiPropertyType.String);
return extendedPropertyDefinition;
}
Item boundItem = Item.bind(this.exchangeService, appointmentId, getPropertySetKnown());
jiraCateringId = boundItem.getExtendedProperties().getItems().stream()
.filter(property -> property.getPropertyDefinition().getName().equals(CATERING_JIRA_ID)).findFirst()
.orElse(null);
Does anyone know in which DefaultExtendedPropertySet the Propertie could be found set by Office.js ?
Is there a way to get all Propertis using EWS with no need to define an own Definition?
Is there any Debug Tool in Outlook / Exchange to see the Customproperties in an Item?

Answer 1

As mentioned by #Glen Scales this should answer your question.
Also you can refer the doc Working with extended properties for more details on accessing extended properties from EWS.