Simple Node.js Utility module to enable easy creation of models using node-mongodb-native

mongodb-dao.js

/*
Simple Node.js Utility module to enable easy creation of models using node-mongodb-native

Useage:-
  var dao = require('./mongodb-dao');

  exports.NewClient = function(clientId, plan){
    return {
      clientId: clientId,
      plan: plan,
      joinDate: new Date()
    };
  };
  exports.StoreClient = function (Client, theCallbackFunction) {
    dao.Store('clients', Client, {
      clientId: Client.clientId
    }, theCallbackFunction);
  };

  exports.DeleteClient = function (ClientId, theCallbackFunction) {
    dao.Delete('clients', {
      clientId: ClientId
    }, theCallbackFunction);
  };

  exports.RetrieveClient = function (ClientId, theCallbackFunction) {
    dao.FindOne('clients', {
      clientId: ClientId
    }, theCallbackFunction);
  };

  exports.RetrieveClients = function (theCallbackFunction) {
    dao.Find('clients', {}, theCallbackFunction);
  };


 */

//setup the db connection
var mongo = require('mongodb');
var DBServer = mongo.Server;
var Db = mongo.Db
var config = {
  mongo_db_address = 'localhost';
  mongo_db_port = 27017;
  mongo_db_name = 'mydatabase';
  mongo_db_user = null;
  mongo_db_pass = null;
}

var dbServer = new DBServer(config.mongo_db_address, config.mongo_db_port, {
  auto_reconnect: true
});
var db = new Db(config.mongo_db_name, dbServer, {
  safe: false
});

var checkDB = function (successCallback, errorCallback) {
    if(db.openCalled === false) {
      db.open(function (err, db_p) {
        if(err) {
          errorCallback(err);
        } else {
          if(config.mongo_db_user != null) {
            db.authenticate(config.mongo_db_user, config.mongo_db_pass, function (err, replies) {
              if(err) {
                errorCallback(err);
              } else {
                successCallback();
              }
            });
          } else {
            successCallback();
          }
        }
      });
    } else {
      successCallback();
    }
  }

exports.Store = function (collectionName, item, key, theCallbackFunction) {
  checkDB(function () {
    delete item['_id'];
    db.collection(collectionName, function (err, items) {
      if(err == null) {
        items.update(key, item, {
          safe: true,
          upsert: true
        }, function (err, result) {
          theCallbackFunction(err, result); //just pass the result back.. lazy, also non-DAO ish... the result has a db semantic?
        });
      } else {
        theCallbackFunction(err, 0); //0 result indicates no update was made
      }
    });
  }, function (err) {
    theCallbackFunction(err, 0);
  });
};

exports.Delete = function (collectionName, key, theCallbackFunction) {
  checkDB(function () {
    db.collection(collectionName, function (err, items) {
      if(err == null) {
        items.remove(key, function () {
          theCallbackFunction(); //just pass the result back.. lazy, also non-DAO ish... the result has a db semantic?
        });
      } else {
        theCallbackFunction(err, 0); //0 result indicates no update was made
      }
    });
  }, function (err) {
    theCallbackFunction(err, 0);
  });
};

exports.FindOne = function (collectionName, key, theCallbackFunction) {
  checkDB(function () {
    db.collection(collectionName, function (err, items) {
      items.findOne(key, function (err, item) {
        if(item != null) {
          theCallbackFunction(item);
        } else {
          theCallbackFunction(null);
        }
      });
    });
  }, function (err) {
    theCallbackFunction(err, 0);
  });
};

exports.Find = function (collectionName, key, theCallbackFunction) {
  checkDB(function () {
    db.collection(collectionName, function (err, itemsLink) {
      itemsLink.find(key).toArray(function (err, items) {
        if(items != null) {
          theCallbackFunction(items);
        } else {
          theCallbackFunction(null);
        }
      });
    });
  }, function (err) {
    theCallbackFunction(err, 0);
  });
};