为什么它在 .each 的每次迭代中显示相同的数据

Question

我试过根据@wifis（基于mac_id）生成数据，但目前数据与以下代码完全相同-

控制器：

class DashboardsController < ApplicationController
  before_action :authenticate_user!
  def show
    @wifis = Wifi.where(user_id: current_user.id)
    pdaily_number_of_logins_data = []
    phourly_total_traffic_data = []
    pper_user_monthly_traffic_data = []
    @wifis.each do |wifi|
      daily_number_of_logins_data = Radacct.fetch("SELECT gd_day(acctstarttime, 'UTC') AS date, COUNT(*) AS count FROM radacct WHERE (`calledstationid` = ?) AND (`acctstarttime` >= ?) GROUP BY date", wifi.mac_id, 1.month.ago)
      pdaily_number_of_logins_data += daily_number_of_logins_data.to_a if daily_number_of_logins_data.to_a
      @daily_number_of_logins = pdaily_number_of_logins_data.collect{|i| [i[:date],i[:count]]}
      hourly_total_traffic_data = Radacct.fetch("SELECT gd_hour_of_day(acctstarttime, 'UTC') AS hour_of_day, ROUND(((SUM(acctinputoctets)+SUM(acctoutputoctets))/1049000)) AS totaltraffic FROM radacct WHERE (`calledstationid` = ?) AND (`acctstarttime` >= ?) GROUP BY hour_of_day", wifi.mac_id, 1.day.ago)
      phourly_total_traffic_data += hourly_total_traffic_data.to_a if hourly_total_traffic_data.to_a
      @hourly_total_traffic = phourly_total_traffic_data.collect{|i| [i[:hour_of_day],i[:totaltraffic]]}
      per_user_monthly_traffic_data = Radacct.fetch("SELECT username, ROUND(((SUM(acctinputoctets)+SUM(acctoutputoctets))/1049000)) AS `traffic` FROM `radacct` WHERE (`calledstationid` = ?) AND (`acctstarttime` >= ?) GROUP BY username", wifi.mac_id, 1.month.ago)
      pper_user_monthly_traffic_data += per_user_monthly_traffic_data.to_a if per_user_monthly_traffic_data.to_a
      @per_user_monthly_traffic = pper_user_monthly_traffic_data.collect{|i| [i[:username],i[:traffic]]}
    end
  end
end

和视图：

% @wifis.each do |wifi| %>
  <h1><%= wifi.mac_id %></h1>
  <%= line_chart @daily_number_of_logins, { discrete: true, library: {hAxis: {title: "Date"}, vAxis: {title: "Number of Logins (daily)"}}} %>
  <%= column_chart @hourly_total_traffic, {library: {hAxis: {title: "Hour"}, vAxis: {title: "Traffic in Megabytes (hourly)"}}} %>
  <%= pie_chart @per_user_monthly_traffic, discrete: true %>
<% end %>

我已经根据这个答案尝试了以上方法，但我遇到的问题是控制器和视图中都使用了@wifi 对象：Loop within Loop in Rails Controller

Answer 1

问题是您的控制器操作中的循环运行并在每次迭代时覆盖实例变量。所以只剩下最后一次迭代。如果你想为每个 wifi 保存数据，你需要另一个数据结构，而不是普通的 ivars。也许是一个哈希，其中 wifi 是关键。

@counters = {}
@wifis.each do |wifi|
  @counters[wifi] ||= {}
  @counters[wifi][:daily_number_of_logins] = ...

然后在视图中

  <% @wifis.each do |wifi| %>
    <%= line_chart @counters[wifi][:daily_number_of_logins] %>
  <% end %>

为什么它在 .each 的每次迭代中显示相同的数据

Why is it showing identical data at each iteration of .each

ruby

sequel

ruby-on-rails-4