小编cri*_*lla的帖子

假设我们有以下由聚合管道生成的文档：

[
  {
    "_id": ObjectId("5a934e000102030405000000"),
    "description": "description for item 1",
    "item_code": "00001"
  },
  {
    "_id": ObjectId("5a934e000102030405000001"),
    "description": "description for item 2",
    "item_code": "00002"
  },
  {
    "_id": ObjectId("5a934e000102030405000002"),
    "description": "description for item 3",
    "item_code": "00003"
  },
  {
    "_id": ObjectId("5a934e000102030405000003"),
    "extrafield": "extra field for item 2",
    "item_code": "00002"
  }
]

如何将相同的文档合并item_code为一个，保留所有属性？想要的结果：

[
  {
    "description": "description for item 1",
    "item_code": "00001"
  },
  {
    "description": "description for item 2",
    "extrafield": "extra field for item 2",
    "item_code": "00002"
  },
  {
    "description": "description for …

我正在尝试在托管于谷歌云平台的 MERN 项目中实现谷歌跟踪。

我已经按照 Google 提供的指南和示例进行操作，但我无法使其以任何方式工作。

import gCloudTrace from '@google-cloud/trace-agent';
// initialize gcloud trace
if (process.env.NODE_ENV === 'production') {
  console.log(`Starting google cloud trace...`);
  const tracer = gCloudTrace.start();
  console.log(JSON.stringify(tracer,null,2));
};

import express from 'express';
import apiRoute  from './api.js';
import indexRoute from './index/indexRoute.js';

try {

  // setup
  const host = process.env.HOST || '0.0.0.0';
  const port = process.env.PORT || 5050;
  const app = express();

  // routes
  app.use('/', indexRoute);
  app.use('/api', checkGloblalSettings, apiRoute);

  // create and run HTTP server
  app.listen(port, host, () => {
    console.log(`EXPRESS …