I'm making a game with socket.io and nodejs, and I'm making a module called rooms.js, this module require users.js module and fiveSocket.js module
but when I call Rooms.New from the main server file, it says that fiveSocket is undefined, same problem when Rooms.New calls a users.js function, I got TypeError: Cannot read property 'getSocketIDbyId' of undefined
rooms.js:
var mysql = require('../mysql/mysql.js');
var headers = require('./headers.js');
var users = require('./users.js');
var fiveSocket = require('./sockets.js');
var Rooms = {
Obj: {},
Room: function(data) {
var room = this;
this.name = data.name;
this.users = [];
this.floorCode = data.floor;
this.description = data.desc;
this.maxUsers = data.maxUsers;
this.owner = data.owner;
this.setTime = new Date().getTime();
this.dbID = data.dbID;
this.doorx = data.doorx;
this.doory = data.doory;
this.doordir = data.doordir;
},
New: function(socketID, roomID) {
var keys = Object.keys(Rooms.Obj).length;
var id = keys + 1;
var callback = function(row) {
fiveSocket.emitClient(socketID, headers.roomData, {
title: row.title,
desc: row.description,
mapStr: row.floorCode,
doorx: row.doorx,
doory: row.doory,
doordir: row.doordir
});
var uid = users.getIdBySocketID(socketID);
users.Obj[uid].curRoom = roomID;
var rid = Rooms.getIdByDbID(roomID);
Rooms.Obj[rid].users.push(uid);
}
if(Rooms.getIdByDbID(roomID) != false) {
var room = Rooms.getIdByDbID(roomID);
var row = { title: room.name, description: room.description, floorCode: room.foorCode, doorx: room.doorx, doory: room.doory, doordir: room.doordir };
callback(row);
} else {
mysql.Query('SELECT * FROM rooms WHERE id = ? LIMIT 1', roomID, function(rows) {
if(rows.length > 0) {
var row = rows[0];
Rooms.Obj[id] = new Rooms.Room({name: row.title, floorCode: row.floorCode, desc: row.description, maxUsers: row.maxUsers, owner: row.owner, dbID: row.id, doorx: row.doorx, doory: row.doory, doordir: row.doordir});
callback(row);
}
});
}
},
removeUser: function(DBroomID, userID) {
var rid = Rooms.getIdByDbID(DBroomID);
var room = Rooms.Obj[rid];
var index = room.indexOf(userID);
if (index > -1) array.splice(index, 1);
},
Listener: function(users) {
setInterval(function(){
for(var roomID in Rooms.Obj) {
var room = Rooms.Obj[roomID];
// send users coordinates
room.users.forEach(function(uid) {
var socketID = users.getSocketIDbyId(uid);
var data = Rooms.getUsersInRoomData(roomID);
fiveSocket.emitClient(socketID, headers.roomUsers, data);
});
// unload inactive rooms (no users after 10 seconds)
var activeUsers = room.users.length;
var timestamp = room.setTime;
var t = new Date(); t.setSeconds(t.getSeconds() + 10);
var time2 = t.getTime();
if(activeUsers <= 0 && timestamp < time2) {
Rooms.Remove(roomID);
}
}
}, 1);
},
getUsersInRoomData: function(roomID) {
var room = Rooms.Obj[roomID];
var obj = {};
room.users.forEach(function(uid) {
var user = users.Obj[uid];
obj[uid] = {
username: user.username,
position: user.position,
figure: user.figure
};
});
return obj;
},
Remove: function(id) {
delete Rooms.Obj[id];
},
getIdByDbID: function(dbID) {
var result = null;
for(var room in Rooms.Obj) {
var u = Rooms.Obj[room];
if(u.dbID == dbID) var result = room;
}
if(result == null) return false;
else return result;
},
getDbIDbyId: function(id) {
return Rooms.Obj[id].dbID;
}
}
Rooms.Listener();
module.exports = Rooms;
EDIT: (if it can be helpful)
When I console.log fiveSocket on the main file
When I console.log fiveSocket on the rooms.js file
EDIT2: When I've removed var users = require('./users.js'); from fiveSocket, when I console.log it in rooms.js it works, why ?
EDIT3: I still have the problem
If you need the others modules sources:
Users.JS: http://pastebin.com/Ynq9Qvi7
sockets.JS http://pastebin.com/wpmbKeAA
"Rooms" requires "Users" and vice versa, so you are trying to perform "circular dependency".
Quick search for node.js require circular dependencies gives a lot of stuff, for example :
"Circular Dependencies in modules can be tricky, and hard to debug in
node.js. If module A requires('B') before it has finished setting up
it's exports, and then module B requires('A'), it will get back an
empty object instead what A may have intended to export. It makes
logical sense that if the export of A wasn't setup, requiring it in B
results in an empty export object. All the same, it can be a pain to
debug, and not inherently obvious to developers used to having those
circular dependencies handled automatically. Fortunately, there are
rather simple approaches to resolving the issue."
or
How to deal with cyclic dependencies in Node.js
Related
As the title states, I'm having trouble with Promises in Parse.
I'm struggling to firstly understand exactly how Promises themselves work, especially in Parse.
I have been stuck on this for about three weeks and the closest I've come to a solution is having an empty array returned.
What I'm trying to do is scrape a site and then create objects from the table (this is working)
Where there trouble comes in, is I am then running a for loop on the results and querying each Dam name to get the resulting objectid from the database.
Here is my code:
var c = new Crawler({
maxConnections: 10,
// This will be called for each crawled page
callback: function(err, res, done) {
if (err) {
console.log(err);
} else {
var $ = res.$;
// $ is Cheerio by default
//a lean implementation of core jQuery designed specifically for the server
console.log($("title").text());
}
done();
}
});
The Function which Creates objects from the Dom and adds them to an array:
function getDamObjects(Dom) {
var dom = Dom;
var LevelObjects = [];
for (i = 1; i < dom.length - 1; i++) {
var TableRow = dom.eq(i);
var NameString = TableRow.children().eq(0).text();
var RiverString = TableRow.children().eq(1).text();
var FSCString = TableRow.children().eq(4).text();
var ThisWeekString = TableRow.children().eq(5).text();
var LastWeekString = TableRow.children().eq(6).text();
var LastYearString = TableRow.children().eq(7).text();
NameString = NameString.replace('#', '');
NameString = NameString.replace('$', '');
NameString = NameString.replace('&', '');
NameString = NameString.replace('#', '');
ThisWeekString = ThisWeekString.replace('#', '');
ThisWeekString = ThisWeekString.replace('$', '');
ThisWeekString = ThisWeekString.replace('&', '');
ThisWeekString = ThisWeekString.replace('#', '');
LastWeekString = LastWeekString.replace('#', '');
LastWeekString = LastWeekString.replace('$', '');
LastWeekString = LastWeekString.replace('&', '');
LastWeekString = LastWeekString.replace('#', '');
LastYearString = LastYearString.replace('#', '');
LastYearString = LastYearString.replace('$', '');
LastYearString = LastYearString.replace('&', '');
LastYearString = LastYearString.replace('#', '');
var level = {};
/*
getDamObject(NameString).then(function(DamObject){
let DamID = DamObject.id;
*/
level['Dam'] = NameString; //DamID;
level['ThisWeek'] = ThisWeekString;
level['LastWeek'] = LastWeekString;
level['LastYear'] = LastYearString;
LevelObjects.push(level);
};
return LevelObjects;
};
The Get Dam Object Code:
function getDamObject(Dam) {
var promise = new Parse.Promise();
var query = new Parse.Query("DayZeroDams");
query.equalTo("Name", Dam);
query.first().then(function(DamObject) {
promise.resolve(DamObject);
}, function(error) {
promise.reject(error);
});
return promise;
}
The Cloud Code Called:
Parse.Cloud.define('jsdom', function(request, response) {
c.queue([{
uri: 'xxxxxx',
// The global callback won't be called
callback: function(err, res, done) {
if (err) {
response.error(err);
} else {
var $ = res.$;
var ResultsArray = [];
var dom = res.$('#mainContent_tw').children('tr');
return Parse.Promise.as().then(function() {
var promise = Parse.Promise.as();
var LevelObjects = getDamObjects(dom);
_.each(LevelObjects, function(DamLevel) {
promise = promise.then(function() {
var Name = DamLevel["Dam"];
var query = new Parse.Query("DayZeroDams");
query.equalTo("Name", Name);
return query.first().then(function(result) {
let damID = result.id;
ResultsArray.push(damID);
return Parse.Promise.as();
}, function(error) {
response.error(error);
});
});
});
return promise;
}).then(function() {
response.success(ResultsArray);
}, function(error) {
response.error(error);
});
//response.success(LevelObjects);
}
done();
}
}]);
});
Please take note that I am fairly novice when it comes to Javascript, I have only recently started learning it in order to work with my server code.
Convert getDamObjects into an async function and then await the result of each row, pushing it to the array:
function replaceSymbols(input) {
return input.replace(/[#\$&#]/g, '');
}
async function getDamObjects(Dom) {
const dom = Dom;
const levelObjects = [];
for (let i = 1; i < dom.length - 1; i++) {
const children = dom.eq(i).children();
const NameString = replaceSymbols(children.eq(0).text());
const RiverString = children.eq(1).text();
const FSCString = children.eq(4).text();
const ThisWeek = replaceSymbols(children.eq(5).text());
const LastWeek = replaceSymbols(children.eq(6).text());
const LastYear = replaceSymbols(children.eq(7).text());
const Dam = await getDamObject(NameString);
levelObjects.push({
Dam,
ThisWeek,
LastWeek,
LastYear,
});
}
return levelObjects;
}
Remember that now that getDamObjects is an async function, it will return a Promise that resolves to the array once iterations are complete. Consume it using await getDamObjects in another async function (or use .then)
I am working on small idea to collect errors from pages and to store them in DB and then use graph API to display information visually.
There is 8 sites and on each of them there is 100 entries - so 800 transactions per time.
I loop through each site and then sub-loop through table of errors and collect them.
I got it working if I make insert query on each of those sub-loops for all 800 entries but I am getting some sort of memory leak from so many transactions and after few minutes - Node breaks due to memory exceeding.
So I tried queuing all 800 entries into Array of Arrays and then performing multi-insert at the end of every iteration but I am getting ER_PARSE_ERROR.
var tabletojson = require('tabletojson');
var mysql = require("mysql");
var striptag = require("striptags");
var fs = require("fs");
var path = require('path');
var startCollector;
var iterations = 0;
var insertions = 0;
var duplicated = 0;
var datas = [];
var clients = ["ClientA", "ClientB", "ClientC", "ClientD", "ClientE", "ClientF", "ClientG", "ClientH"];
var appDir = path.dirname(require.main.filename);
var errorList = ["err1", "err2", "err3", "err4", "err5", "err6"];
var con = mysql.createPool({
host: "localhost",
user: "User",
password: "Password",
database: "errors"
});
function CollectErrors() {
startCollector = new Date();
for(var a = 0; a < clients.length; a++) {
(function(a) {
tabletojson.convertUrl("http://example.com" + clients[a] + "/page.php?limit=100", { stripHtmlFromCells: false }, function(response) {
var rs = response[0];
for(var l = rs.length-1; l > -1; l--) {
var newDate = formatDate(striptag(rs[l]["Date"]), striptag(rs[l]["Time"]));
var user = getUser(striptag(rs[l]["User"]));
var msg = striptag(rs[l]["Error"]);
var splitError = rs[l]["Error"].split("<a href=\"");
var link = getUrl(splitError[1]);
var id = getId(link);
var type = getType(striptag(splitError[0]));
var temp = [newDate, link, type, user, clients[a], id, msg];
datas.push(temp);
}
});
})(a);
}
con.getConnection(function(err, connection) {
connection.query("INSERT IGNORE INTO entries (time, url, type, author, client, uid, message) VALUES ?", [datas], function(err, rows) {
console.log(err);
});
connection.release();
datas = [];
});
setTimeout(CollectErrors, 10000);
}
function formatDate(date, time) {
var newdate = date.split("/").reverse().join("-");
var newtime = time+":00";
return newdate + " " + newtime;
}
function getUrl(uri) {
return "http://example.com/"+uri.split("\">Details")[0];
}
function getId(url) {
return decodeURIComponent((new RegExp('[?|&]' + "id" + '=' + '([^&;]+?)(&|#|;|$)').exec(url) || [null, ''])[1].replace(/\+/g, '%20')) || null;
}
function getType(error) {
for(var a = 0; a < errorList.length; a++) {
if(error.indexOf(errorList[a]) !== -1) {
return errorList[a];
}
}
return "Other";
}
function getUser(user) {
if(user == "" || user == " " || user == null) {
return "System";
}
return user;
}
CollectErrors();
I've tried mysql.createConnection too but that also gave me same issue.
I've been stuck for past 12 hours and I can't see what's wrong, I've even tried populating Datas table with just strings but got same error.
I've changed your code to use ES6 and correct modules features.
Useful links: correct pooling with mysql, correct insert query, async/await, IIFE, enhanced object
const tabletojson = require('tabletojson'),
mysql = require("mysql"),
striptag = require("striptags"),
fs = require("fs"),
path = require('path');
const startCollector,
iterations = 0,
insertions = 0,
duplicated = 0;
let datas = [];
const clients = ["ClientA", "ClientB", "ClientC", "ClientD", "ClientE", "ClientF", "ClientG", "ClientH"];
const appDir = path.dirname(require.main.filename);
const errorList = ["err1", "err2", "err3", "err4", "err5", "err6"];
const con = mysql.createPool({
host: "localhost",
user: "User",
password: "Password",
database: "errors"
});
// We'll use async/await from ES6
const collectErrors = async() => {
// Up to here I've only changed syntax to ES6
let startCollector = new Date();
// We'll try to iterate through each client. And we use here for..of syntax to allow us using await
for (let client of clients) {
// Please, check that client value return correct data. If not, change for..of to your for..each and client variable to clients[a]
const tbj = await tabletojson.convertUrl("http://example.com" + client + "/page.php?limit=100", {
stripHtmlFromCells: false
});
const result = tgj[0];
for (rs of result) {
// I can't check this part, but I hope your example was with correct values.
let newDate = formatDate(striptag(rs[l]["Date"]), striptag(rs[l]["Time"]));
let user = getUser(striptag(rs[l]["User"]));
let link = getUrl(splitError[1]);
let msg = striptag(rs[l]["Error"]);
let id = getId(link);
let splitError = rs[l]["Error"].split("<a href=\"");
let getType = getType(striptag(splitError[0]));
// ES6 enhanced object syntax
datas.push({
newDate,
user,
msg,
id,
splitError,
link,
getType,
temp: [newDate, link, type, user, client, id, msg]
});
}
}
// OK, here we have fulfilled datas array. And we want to save it.
con.getConnection((err, connection) => {
// Please, notice, here I've changed your insert query to prepared statement.
connection.query("INSERT IGNORE INTO entries SET ?", datas, (err, rows) => {
console.log(err);
connection.release();
datas = [];
});
});
// I don't see why do you need timeout here, so I've left it commented.
// setTimeout(CollectErrors, 10000);
};
// Here your other methods go....
// And to call your async function we'll use IIFE
(async() => {
await collectErrors();
})();
Probably there may be errors with mysql insert, but that's not for sure. If occurred, please write in comments and I'll help you with that.
Having a really weird problem with Angular and wondering if anyone has encountered this.
var transformResponse = function(data) {
var jobs = data.job.map(convertResponseToJob);
console.log(jobs);
// return jobs;
}
This logs the correct array with all the values within it, but this logs an array of the same length with undefined as each value.
var transformResponse = function(data) {
var jobs = data.job.map(convertResponseToJob);
console.log(jobs);
return jobs;
}
This may be something really obvious as I haven't worked with Angular factories very much, but I couldn't find an explanation.
Other Functions:
function convertResponseToJob(response){
var jobObj = new Job(response.id, response.clientId, response.book);
jobObj.bookName = response.book.name;
jobObj.submitDate = response.createDate;
jobObj.priority = response.priority;
jobObj.status = response.status;
jobObj.sequence = response.seqOrder;
return jobObj;
}
function Job(jobId, client, book) {
this.jobId = jobId;
this.client = client;
this.book = book;
this.bookName = null;
this.submitDate = null;
this.priority = 2;
this.sequence = 2;
this.status = null;
}
I want to customize an autocomplete function to Codemirror.
So I have build this code:
CodeMirror.commands.autocomplete = function (cm) {
var arrayTabNONDefault = new Array();
var stringaCampi = null;
var arrayTabellaCampo = null;
var textVal = cm.getValue();
textVal = textVal.toUpperCase();
var res = textVal.match("SELECT(.*)FROM");
if (res != null) {
stringaCampi = res[1];
arrayTabellaCampo = stringaCampi.split(",");
var nomeTab = null;
for (var i = 0; i < arrayTabellaCampo.length; i++) {
nomeTab = (arrayTabellaCampo[i].split(".")[0]).trim();
if (hintTables[nomeTab] == null)
hintTables[nomeTab] = new Array();
} //FINE FOR
} //FINE IF
CodeMirror.showHint(cm, CodeMirror.hint.sql, {
tables: hintTables
});
cm.on("beforeChange", function (cm, change) {
var before = cm.getRange({ line: 0, ch: 0 }, change.from);
var text = cm.getRange(change.from, change.to);
var after = cm.getRange(change.to, { line: cm.lineCount() + 1, ch: 0 });
if (before.indexOf("FROM") !== -1)
// alert("Ho scritto FROM");
console.log("before change", before, text, after);
});
cm.on("change", function (cm, change) {
var from = change.from;
var text = change.text.join("\n");
var removed = change.removed.join("\n");
var to = cm.posFromIndex(cm.indexFromPos(from) + text.length);
var before = cm.getRange({ line: 0, ch: 0 }, from);
var after = cm.getRange(to, { line: cm.lineCount() + 1, ch: 0 });
if (before.indexOf("FROM") !== -1)
console.log("after change", before, removed, text, after);
});
} //FINE ESTENSIONE
This is the content of hintTables
var hintTables = { "#T_TF_FilesList": ["FilesListHeaderID", "NumRecord", "FileTypeID", "FileID", "FilesListHeaderID", "NumRecord"],
"#T_TF_SelectedItems": ["EventHeaderID", "ItemType", "ItemID1", "ItemID2", "EventHeaderID", "ItemType", "ItemID1", "ItemID2"],
"#T_TFT_CacheSearchCriteriaHeaders": ["ID", "SyncDate", "FileTypeID", "CriteriaExpressionString", "CriteriaExpressionHash", "PageRecordsNumber", "PageNumber", "NumFiles"]
};
So I want that the system should propose a list of this table after I write FROM, or the system should to propose a list of stored procedures after I write EXECUTE.
It is possible to do this?
Are you trying to customize the SQL hint addon? If so, you should make changes inside sql-hint.js (under codemirror/addon/hint).
Basically what you should do is:
1.In your app.js (whatever js file for your main logic) call editor.showHint({hint: CodeMirror.hint.sql) on "change" event;
2.Inside sql-hint.js, return {list: hintTables, from: somePos, to: somePos} when the user types FROM or EXECUTE which can be detected by regular expression or inspecting the tokens at the line. I made up some code for your reference:
var cursor = editor.getCursor();
var tokenAtCursor = editor.getTokenAt(cursor);
if (tokenAtCursor.type == "FROM-and-EXECUTE")
return {list: hintTables,
from: CodeMirror.Pos(cur.line, tokenAtCursor.start),
to: CodeMirror.Pos(cur.line, tokenAtCursor.end)};
If I misunderstand your question and this answer is not helpful, please tell me and I will delete it.
I have the following module :
// vote.js
var db = require(./dirty-wrapper);
module.exports = function vote() {
var obj = {};
// increase the score
obj.inc = function(key) {
var pval = db.get(key);
if (!pval) pval = 0;
db.set(key, pval + 1);
};
// decrease the score
obj.dec = function(key) {
var pval = db.get(key);
if (!pval) pval = 0;
db.set(key, pval - 1);
};
// reset the score to 0
obj.reset = function(key) {
db.set(key, 0);
};
obj.get = function(key) {
return db.get(key);
};
return obj;
};
Which uses this simple wrapper for dirty:
// dirty-wrapper.js
var dirty = require('dirty');
var db = dirty('vote.db');
module.exports = db.on('load', function() {
var obj = {};
obj.set = function(key, val, callback) {
db.set(key, val);
return callback();
};
obj.get = function(key, callback) {
return callback(db.get(key));
};
obj.reset = function(callback) {
db.forEach(function(key, val) {
val = 0;
});
return callback();
};
return obj;
});
and this is my simple client :
// client.js
var vote = require('./vote.js')();
vote.inc('michael');
vote.inc('michael');
vote.inc('michael');
vote.inc('michael');
console.log('michael: ' + vote.get('michael')); // output = michael: 4
Problem is that when the run stops and I start the client again, The output is again michael: 4
after the second run, vote.db contains the following :
$ cat vote.db
{"key":"michael","val":1}
{"key":"michael","val":4}
{"key":"michael","val":4}
{"key":"michael","val":4}
{"key":"michael","val":1}
{"key":"michael","val":4}
{"key":"michael","val":4}
{"key":"michael","val":4}
First, would be great if someone would explain the append-only strategy. Second I would like to understand why node-dirty doesn't persists even though it writes to the disk each run.
Thanks ;)
You are using the database before it has loaded, and are essentially starting from 0 every time. module.exports runs immediately, but the load event has to wait for the disk io.
You have to wait for the file to be loaded and parsed before you get values from the db.
From the readme:
dirty event: 'load' (length)
Emitted once the database file has finished loading. It is not safe to access records before this event fires. Writing records however should be fine.
You can remove the dirty-wrapper file, and just use vote as the wrapper. Make a minor change to how you are using it, keeping in mind that you have to wait for the load event.
Your vote interface:
// vote.js
var events = require('events');
var dirty = require('dirty');
var db = dirty('vote.db');
var obj = new events.EventEmitter();
// increase the score
obj.inc = function(key) {
var pval = db.get(key);
if (!pval) pval = 0;
db.set(key, pval + 1);
};
// decrease the score
obj.dec = function(key) {
var pval = db.get(key);
if (!pval) pval = 0;
db.set(key, pval - 1);
};
// reset the score to 0
obj.reset = function(key) {
db.set(key, 0);
};
obj.get = function(key) {
return db.get(key);
};
db.on('load', function() {
obj.emit('load');
});
module.exports = obj;
And your main script:
// client.js
var vote = require('./vote.js');
vote.on('load', function() {
vote.inc('michael');
vote.inc('michael');
vote.inc('michael');
vote.inc('michael');
console.log('michael: ' + vote.get('michael')); // output = michael: 4
});
This will output 4 more votes every run.