测试与Firebase实时数据库的连接，点击参考确认连接

Question

我想测试一个与我的firebase实时数据库的连接。你能做这个吗？如何连接到我的数据库并获取快照，然后对返回的数据进行断言？我没有找到通过引用做很多事情的例子，甚至只是验证真正的连接。

我正在使用v1.0.0的firebase函数， 摩卡，打字稿，柴。

// Test framework.
import 'mocha';
// Assertion library.
import { use, expect, assert } from 'chai';
// Standalone test spies, stubs and mocks.
import * as sinon from 'sinon';
// Extends Chai with assertions for the Sinon.JS
import * as sinonChai from 'sinon-chai';
use(sinonChai);

const admin = require('firebase-admin');

const test = require('firebase-functions-test')({
    databaseURL: 'https://<myappname>.firebaseio.com',
    storageBucket: '<myappname>.appspot.com',
    projectId: '<myappname>',
}, './<myappname>-firebase-adminsdk-9pvzn-9999999999.json');

admin.initializeApp();

describe('Suite: Connection to Firebase Database', () => {
    let index;

    before(() => {
        // Require index.js and save the exports inside a namespace called index.
        // I am not testing any functions here...just a connection to the database.
    });


    after(() => {
        // Do cleanup tasks.
        test.cleanup();
    });


    it('should connect to firebase and make sure there is data', () => {

        const ref = admin.database().ref('/organizations/1235/yieldTag/');

        return ref.orderByChild('pickDateTime')
        .startAt(100)
        .endAt(100000000000)
        .once('value')
        .then(snapshot => {
            expect(snapshot).is.not.null; // <-- this passes
            expect(snapshot.ref.path.pieces_[0]).is.equal('organizations'); // <-- my ref shows up here
            console.log('exists?: ' + snapshot.exists()); // <-- snapshot never "exists." 
            if (snapshot.exists()) {
                expect(snapshot.length).is.greaterThan(0);
            }
            else {
                console.log('cn: snapshot not provided'); // <-- my code falls here.
            }
        }).catch((error) => {
            console.log('there was an error in "should connect to firebase and make sure there is data." ' + error);
        });
    });
});

这是我的package.json

{
  "name": "functions",
  "version": "0.0.0",
  "main": "lib/index.js",
  "scripts": {
    "build": "tsc",
    "watch": "tsc --watch",
    "test": "mocha -r ts-node/register tests/**/*.spec.ts",
    "deployDev": "tsc && firebase deploy --project dev --only functions",
    "deployProd": "tsc && firebase deploy --project prod --only functions",
    "lint": "tslint -p tsconfig.json src/**/*.ts -e tests/**/*.ts"
  },
  "description": "Cloud Functions for Firebase",
  "dependencies": {
    "@types/firebase": "^2.4.32",
    "cors": "^2.8.4",
    "fecha": "^2.3.3",
    "firebase-admin": "^5.12.0",
    "firebase-functions": "^1.0.2",
    "json2typescript": "^1.0.5",
    "lodash": "^4.17.10",
    "superagent": "^3.8.3"
  },
  "devDependencies": {
    "@types/chai": "^4.1.3",
    "@types/cors": "^2.8.4",
    "@types/mocha": "^5.2.0",
    "@types/sinon": "^4.3.1",
    "@types/sinon-chai": "^2.7.29",
    "chai": "^4.1.2",
    "chai-as-promised": "^7.1.1",
    "concurrently": "^3.5.1",
    "firebase-functions-test": "^0.1.2",
    "mocha": "^5.1.1",
    "rimraf": "^2.6.2",
    "rollup": "^0.58.2",
    "rollup-plugin-node-resolve": "^3.3.0",
    "sinon": "^4.5.0",
    "sinon-chai": "^3.0.0",
    "ts-node": "^6.0.2",
    "tslint": "^5.10.0",
    "typescript": "^2.8.3"
  },
  "private": true
}