在本地测试云功能时，event.params始终为空

Question

考虑以下简单的onCreate触发器功能。

exports.sampleFunction = functions.database.ref('/foo/{recordID}')
.onCreate(event => {
    console.log(event);
});

我使用firebase experimental:functions:shell在本地调用函数以使用以下命令进行测试：

sampleFunction('/TEST-DATA/', {params: {recordID: "Test Param Value"}});

我收到以下输出，请注意event.params为空。

info: { eventId: '4282b14f-edea-4497-8bee-b045023b0a84',
  timestamp: '2017-10-15T16:12:59.812Z',
  data: 
   DeltaSnapshot {
     app: 
      FirebaseApp {
        firebaseInternals_: [Object],
        services_: [Object],
        isDeleted_: false,
        name_: '__admin__',
        options_: [Object],
        database: [Function: bound ],
        auth: [Function: bound ],
        messaging: [Function: bound ],
        INTERNAL: [Object] },
     adminApp: 
      FirebaseApp {
        firebaseInternals_: [Object],
        services_: [Object],
        isDeleted_: false,
        name_: '__admin__',
        options_: [Object],
        database: [Function: bound ],
        auth: [Function: bound ],
        messaging: [Function: bound ],
        INTERNAL: [Object] },
     _path: '/foo/Test Param Value',
     _data: null,
     _delta: '/TEST-DATA/',
     _newData: '/TEST-DATA/' },
  eventType: 'providers/google.firebase.database/eventTypes/ref.create',
  resource: 'projects/_/instances/silk-39c1f/refs/foo/Test Param Value',
  auth: { admin: true },
  params: {} }
info: Execution took 10 ms, user function completed successfully