text: const mongoose = require('mongoose');
  
  const GroupSchema = new mongoose.Schema({
      user: {
          type: mongoose.Schema.Types.ObjectId,
          refPath: 'provider',
      },
      provider: {
          type: String,
          required: true,
          default: 'user',
          enum: ['user', 'facebook_user', 'google_user'],
      },
      name: {
          type: String,
          required: true,
      },
      public: {
          type: Boolean,
          required: true,
      },
      city: {
          type: String,
      },
      introduction: {
          type: String,
      },
      locations: [
          {
              user: {
                  type: mongoose.Schema.Types.ObjectId,
                  refPath: 'provider',
              },
              provider: {
                  type: String,
                  required: true,
                  default: 'user',
                  enum: ['user', 'facebook_user', 'google_user'],
              },
              name: {
                  type: String,
                  required: true,
              },
              address: {
                  type: String,
                  required: true,
              },
              url: {
                  type: String,
              },
              latLng: {
                  type: Object,
                  required: true,
              },
              photo: {
                  type: String,
              },
              description: {
                  type: String,
              },
              placeId: {
                  type: String,
              },
          },
      ],
  });
  
  module.exports = mongoose.model('group', GroupSchema);
  