Operational Data Models

Queue Snapshot

Filter Ticket Records

A small list of record-like maps can model a queue snapshot without any host service. The selector changes which ticket status the report highlights.

Program

Play the program to choose the ticket status and inspect the queue snapshot.

queue_snapshot_model.dart 
void main() {
  var wantedStatus = ;
  var tickets = [
    {'status': 'open', 'severity': 'high'},
    {'status': 'waiting', 'severity': 'normal'},
    {'status': 'open', 'severity': 'normal'},
  ];
  var visible = tickets.where((ticket) => ticket['status'] == wantedStatus).length;
  var high = tickets.where((ticket) => ticket['severity'] == 'high').length;
  var line = '$wantedStatus tickets=$visible high=$high';
  print(line);
}

void main() {
  var wantedStatus = ;
  var tickets = [
    {'status': 'open', 'severity': 'high'},
    {'status': 'waiting', 'severity': 'normal'},
    {'status': 'open', 'severity': 'normal'},
  ];
  var visible = tickets.where((ticket) => ticket['status'] == wantedStatus).length;
  var high = tickets.where((ticket) => ticket['severity'] == 'high').length;
  var line = '$wantedStatus tickets=$visible high=$high';
  print(line);
}
record-like maps The ticket maps carry only the fields needed by the snapshot.
where `where` keeps rows whose status matches the selected value.
summary line The output reports the selected bucket and one independent severity count.