discourse/app/models/user_visit.rb

# frozen_string_literal: true

class UserVisit < ActiveRecord::Base
  belongs_to :user

  def self.counts_by_day_query(start_date, end_date, group_id = nil)
    result = where("visited_at >= ? and visited_at <= ?", start_date.to_date, end_date.to_date)

    if group_id
      result = result.joins("INNER JOIN users ON users.id = user_visits.user_id")
      result = result.joins("INNER JOIN group_users ON group_users.user_id = users.id")
      result = result.where("group_users.group_id = ?", group_id)
    end
    result.group(:visited_at).order(:visited_at)
  end

  def self.count_by_active_users(start_date, end_date)
    sql = <<~SQL
      WITH visits_in_mau_range AS (
        SELECT user_id, visited_at AS d
        FROM user_visits
        WHERE visited_at >= :start_date::DATE - 29
          AND visited_at <= :end_date::DATE
      ),
      visit_island_starts AS (
        SELECT user_id, d,
          CASE
            WHEN lag(d) OVER (PARTITION BY user_id ORDER BY d) >= d - 30 THEN 0
            ELSE 1
          END AS new_island
        FROM visits_in_mau_range
      ),
      visit_islands AS (
        SELECT user_id, d, sum(new_island) OVER (PARTITION BY user_id ORDER BY d) AS grp
        FROM visit_island_starts
      ),
      active_ranges AS (
        SELECT min(d) AS start_d, max(d) + 29 AS end_d
        FROM visit_islands
        GROUP BY user_id, grp
      ),
      active_range_events AS (
        SELECT start_d AS day, 1 AS delta FROM active_ranges
        UNION ALL
        SELECT end_d + 1 AS day, -1 AS delta FROM active_ranges
      ),
      daily_active_deltas AS (
        SELECT day, sum(delta) AS delta
        FROM active_range_events
        GROUP BY day
      ),
      days AS (
        SELECT generate_series(
          (SELECT min(day) FROM daily_active_deltas),
          :end_date::DATE,
          INTERVAL '1 day'
        )::DATE AS day
      ),
      rolling_mau AS (
        SELECT days.day,
          sum(coalesce(daily_active_deltas.delta, 0)) OVER (ORDER BY days.day) AS mau
        FROM days
        LEFT JOIN daily_active_deltas ON daily_active_deltas.day = days.day
      ),
      dau AS (
        SELECT visited_at AS date, count(*) AS dau
        FROM user_visits
        WHERE visited_at >= :start_date::DATE
          AND visited_at <= :end_date::DATE
        GROUP BY visited_at
      )
      SELECT dau.date, dau.dau, rolling_mau.mau
      FROM dau
      JOIN rolling_mau ON rolling_mau.day = dau.date
      ORDER BY dau.date
    SQL

    DB.query_hash(sql, start_date: start_date, end_date: end_date)
  end

  # A count of visits in a date range by day
  def self.by_day(start_date, end_date, group_id = nil)
    counts_by_day_query(start_date, end_date, group_id).count
  end

  def self.mobile_by_day(start_date, end_date, group_id = nil)
    counts_by_day_query(start_date, end_date, group_id).where(mobile: true).count
  end

  def self.counts_by_day_and_mobile(start_date, end_date, group_id: nil)
    sql = <<~SQL
      SELECT
        visited_at,
        mobile,
        COUNT(*) AS visit_count,
        SUM(COUNT(*)) OVER () AS total
      FROM user_visits
      #{"INNER JOIN group_users ON group_users.user_id = user_visits.user_id" if group_id}
      WHERE visited_at >= :start_date AND visited_at <= :end_date
      #{"AND group_users.group_id = :group_id" if group_id}
      GROUP BY visited_at, mobile
      ORDER BY visited_at
    SQL

    params = { start_date: start_date, end_date: end_date, prev_start: start_date - 30.days }
    params[:group_id] = group_id.to_i if group_id

    DB.query(sql, **params)
  end

  def self.ensure_consistency!
    DB.exec <<~SQL
      UPDATE user_stats u set days_visited =
      (
        SELECT COUNT(*) FROM user_visits v WHERE v.user_id = u.user_id
      )
      WHERE days_visited <>
      (
        SELECT COUNT(*) FROM user_visits v WHERE v.user_id = u.user_id
      )
    SQL
  end
end

# == Schema Information
#
# Table name: user_visits
#
#  id         :integer          not null, primary key
#  mobile     :boolean          default(FALSE)
#  posts_read :integer          default(0)
#  time_read  :integer          default(0), not null
#  visited_at :date             not null
#  user_id    :integer          not null
#
# Indexes
#
#  index_user_visits_on_user_id_and_visited_at                (user_id,visited_at) UNIQUE
#  index_user_visits_on_user_id_and_visited_at_and_time_read  (user_id,visited_at,time_read)
#  index_user_visits_on_visited_at_and_mobile                 (visited_at,mobile)
#