await discovery.register('123', 'key1', ConnectionParams.fromTuples([
  'param1', 'val1',
  'param2', 'val2'
]));

var connection = await discovery.resolveAll('123', 'key1'); // Returns {'host': '10.1.1.100', 'port': '8080'}
// Returns [{'host': '10.1.1.100', 'port': '8080'}, {'param1': 'val1', 'param2': 'val2'}]