将多个结果插入到 express.js 路由中的 req 对象

Question

我正在使用 ElasticSearch 运行 Express.js/Node.js 应用程序。我正在尝试查看同一索引中多种类型的结果。我在这里所做的是运行搜索查询并根据查询结果执行第二个搜索查询。通过观察 node.js 控制台，我也可以看到 elasticsearch 为玩家返回的结果。但它们没有插入到我的结果对象/数组中。我正在使用 express 中间件，因为我必须执行两个搜索并将结果显示为一个。

routes/index.js

function searchTeam(req, res, next){
  searchModuleTeams.searchTeams(req.body, function(data) {
    req.teams = data;
    next();
  });
}

function searchPlayer(req, res, next){
  //req.players = [];
  req.teams.forEach(function(team){
    req.body = {searchTerm:team._source.shortName};
    searchModulePlayers.searchPlayers(req.body, function(data){
      req.players.push(data);
      console.log(req.players);
    });
  });
  next();
}

function renderResults(req, res){
  res.render('index',{
    title:'Search Teams and Players',
    teams:req.teams,
    players:req.players
  });
}

router.post('/search-tp',searchTeam, searchPlayer, renderResults);

我通过阅读post1 和post2 提出了这个解决方案。我可以显示团队数组。但是没有任何东西来自玩家数组。我在这里做错了什么。

Answer 1

在你的searchPlayer 函数中，next() 调用应该放在searchPlayers() 调用的回调中，基本上就是你为searchTeam() 函数所做的。

function searchTeam(req, res, next){
  searchModuleTeams.searchTeams(req.body, function(data) {
    req.teams = data;
    next();
  });
}

function searchPlayer(req, res, next){
  req.players = [];                      <--- uncomment this...
  req.teams.forEach(function(team){
    req.body = {searchTerm:team._source.shortName};
    searchModulePlayers.searchPlayers(req.body, function(data){
      req.players.push(data);            <--- ...otherwise this will fail
      next();                            <--- move next() here
    });
  });
}

function renderResults(req, res){
  res.render('index',{
    title:'Search Teams and Players',
    teams:req.teams,
    players:req.players
  });
}

router.post('/search-tp',searchTeam, searchPlayer, renderResults);

正如 Talha Awan 所建议的，您最好不要在中间件中执行此操作，而是使用专用库，例如​​ async one（但还有很多其他库）

import waterfall from 'async/waterfall';

function searchTeam(callback){
  searchModuleTeams.searchTeams(req.body, function(teams) {
    callback(null, teams);
  });
}

function searchPlayer(teams, callback){
  let teamPlayers = [];
  async.each(teams, function(team, teamCallback) {
    let search = {searchTerm: team._source.shortName};
    searchModulePlayers.searchPlayers(search, function(players){
       teamPlayers.push(players);
       teamCallback();
    });
  }, function(err) {
    callback(err, teams, teamPlayers);
  });
}

function renderResults(req, res){
  async.waterfall([
    searchTeam,
    searchPlayer
  ], function (err, teams, players) {
    res.render('index',{
      title:'Search Teams and Players',
      teams: teams,
      players: players
    });
  });
}

router.post('/search-tp', renderResults);