モンゴースの更新機能で「トポロジが破壊されました」エラー

Question

更新コマンドを実行しようとしたときにエラー{ [MongoError: topology was destroyed] name: 'MongoError', message: 'topology was destroyed' }が実行されています。このエラーの私の理解は、データベース接続が切断されたために発生しますが、モデルへの更新呼び出しであるという意味では意味がありません。ここに私のコードの関連部分は次のとおりです。

/*Connect to the Database*/ 
var options = { 
    server: { socketOptions: { keepAlive: 1, connectTimeoutMS: 60000 } }, 
    replset: { socketOptions: { keepAlive: 1, connectTimeoutMS: 60000 } } 
}; 
var mongoose = require('mongoose'), 
    ObjectID = mongoose.Types.ObjectId; 

mongoose.connect('remote.database', options, function(err) { 

    if (err) console.log(err); 
}); 

// Schema for single user 
var user_schema = mongoose.Schema({ 
    //Username, password information 
    username: String, 
    email: String, 
    password: String, 
    name: String, 
    session_ids: [String], 
    session_id_times: [Number], 

    //Khan Academy token, secret for accessing tree of knowledge 
    khan_token: String, 
    khan_secret: String, 

    //Callback is for authenticating with khan 
    khan_callback_id: String, 

    //Proficiencies (data from khan API) 
    proficiencies: [String], 
    additional_skills: [String], 

    //general recommended skills to learn next 
    gen_skill_recs: [String] 
}); 

var User = mongoose.model("user_schema", user_schema); 

/* 
    Logins a user without a password after they have authenticated with 
    Khan. Is only called as a callback to AM.updateAuthentication which 
    sets khan-callback_id to an empty string so that this only works after 
    logging on and authenticating with Khan. 
*/ 
exports.loginAfterAuthentication = function(user, callback){ 
    User.findOne({username: user}, function(err, o){ 
     if(err){ 
      callback('server-error'); 
     }else if(o){ 
      var ids = []; 
      o.session_id_times.forEach(function(el, i) { 
       if(d.getTime()-el > 24*60*60*14) 
        ids.push(i); 
      }); 
      o.session_id_times = o.session_id_times.filter(function(el, i) {return ids.indexOf(i) == -1}); 
      o.session_ids = o.session_ids.filter(function(el, i) {return ids.indexOf(i) == -1}); 
      var session_id = generateSalt(); 
      var session_id_time = d.getTime(); 
      o.session_ids.push(session_id); 
      o.session_id_times.push(session_id_time); 
      User.findOneAndUpdate({username: user}, {session_ids: o.session_ids, session_id_times: o.session_id_times}, function(err, o){ 
       if(err) 
        callback('user-not-found'); 
       else{ 
        callback(null, {'username': user, 'session_id': session_id}); 
        //somewhat time consuming call 
        API.getUserExercises(o.khan_token, o.khan_secret).then(
         function(result){ 
          var addSkills = result; 
          // call to update proficiencies. Somewhat time consuming 
          API.getUserInfo(o.khan_token, o.khan_secret).then(
           function(result){ 
            var profEx = result.proficient_exercises; 
            function isntProficient(el){ 
             return profEx.indexOf(el) == -1; 
            } 
            // Updates proficiencies and removes additional_skills that have been added to 
            // proficiencies 
            console.log(user); 
            console.log(profEx); 
            console.log(addSkills.filter(isntProficient)); 
            User.update({username: user},{proficiencies: profEx, 
             additional_skills: addSkills.filter(isntProficient)}, function(err) { 
              if(err) callback(err); //This is where this error is triggered 
              else updateClonesStatuses(user, function(){}); 
             }); 
           }, function(error){ 
            callback('must-reauthenticate', o); 
           }); 
         }, function(error) { 
          // if API.getUserInfo() throws an error the user's token 
          // and secret are depreciated and they must reauthenticate 
          // with Khan. Should happen very rarely 
          callback('must-reauthenticate', o); 
         }); 
         } 
        }); 
     } else { 
      callback('user-not-found'); 
     } 
    }); 
} 

userは、ユーザーの名前であり、両方profExとaddSkills.filter(isntProficient)は妥当な値です。私はmongoへの接続が何らかの形でどう働くのか誤解していますか？

Answer 1

mongooseでは、ノードサーバーがmongodbサーバーとのTCP接続を失い、最大再試行接続制限を超えた場合、「トポロジ破壊」エラーが発生します。この場合、mongodbとのノードjs接続は理想的なものになり、DB上での操作は実行できません。また、mongodbとの接続要求（ノードサーバーの再起動なし）が発生すると、同じエラーが発生します。