Mongo Aggregate Pipeline Example

mongo-agg.js

const pipeline = [
  {
    $match: { type: 'post' },
  },
  {
    $match: { 
      owner: { $in: ['1', '2', '3'] } 
    },
  },
  {
    $match: {
      name: new RegExp(`.*${q}.*`, "i"),
    },
  },
  {
    $sort: { _id: -1 },
  },
  {
    $limit: 40,
  },
  {
    $lookup: {
      from: "users",
      localField: "_id",
      foreignField: "user_id",
      as: "user",
      pipeline: [
        {
          $match: { role: "manager" },
        },
        {
          $lookup: {
            from: "comments",
            localField: "_id",
            foreignField: "user_id",
            as: "feedbacks",
            pipeline: [
              {
                $match: { type: "feedback" },
              },
            ],
          },
        },
      ],
    },
  },
];

module.exports = { pipeline };