Copying Event in Open Event API Server
The Event Copy feature of Open Event API Server provides the ability to create a xerox copy of event copies with just one API call. This feature creates the complete copy of event by copying the related objects as well like tracks, sponsors, micro-locations, etc. This API is based on the simple method where an object is first removed is from current DB session and then applied make_transient. Next step is to remove the unique identifying columns like “id”, “identifier” and generating the new identifier and saving the new record. The process seems simple but becomes a little complex when you have to generate copies of media files associated and copies of related multiple objects ensuring no orders, attendees, access_codes relations are copied.
The first thing to copy the event is first to get the event object and all related objects first
if view_kwargs.get('identifier').isdigit(): identifier = 'id' event = safe_query(db, Event, identifier, view_kwargs['identifier'], 'event_'+identifier)
Next thing is to get all related objects to this event.
Creating the new event
After removing the current event object from “db.session”, It is required to remove “id” attribute and regenerate “identifier” of the event.
db.session.expunge(event) # expunge the object from session make_transient(event) delattr(event, 'id') event.identifier = get_new_event_identifier() db.session.add(event) db.session.commit()
Updating related object with new event
The new event created has new “id” and “identifier”. This new “id” is added into foreign keys columns of the related object thus providing a relationship with the new event created.
for ticket in tickets: ticket_id = ticket.id db.session.expunge(ticket) # expunge the object from session make_transient(ticket) ticket.event_id = event.id delattr(ticket, 'id') db.session.add(ticket) db.session.commit()
The last step of Updating related objects is repeated for all related objects to create the copy. Thus a new event is created with all related objects copied with the single endpoint.
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