app.js

var port = process.env.PORT || 3001;
var app = require('express')();
var http = require('http').Server(app);
var fs = require('fs');
var bodyParser = require('body-parser')
app.use(bodyParser.urlencoded({ extended: false }))
app.use(bodyParser.json())
var usedIDs = [];

http.listen(port, function () {
    console.log("Starting Server... (" + port + ")");
    usedIDs = loadIDList();
    console.log("Backup Loaded " + "(" + usedIDs.length + ")");
    var stdin = process.openStdin();
    stdin.addListener("data", function (d) {
        var cmd = d.toString().trim();
        var args = cmd.split(" ");
        var result = "Not a command!";
        console.log(cmd + " >> " + result);
        if (args[0] == "new") {
            if (args[1] && args[2]) {
                newPaste(args[1], args[2]);
                result = "Created!";
            } else result = "Please enter 'new string string'";
        }
        console.log(args[0] + " >> " + result);
    });
});

app.post('*', function (req, res) {
    var user = req.body.user || req.get("user");
    var info = req.body.info || req.get("info");
    var json = req.body.json || req.get("json");
    var cmd = req.body.cmd || req.get("cmd") || "UPLOAD";
    var id = req.body.id || req.get("id");
    if (cmd.indexOf("UPLOAD") !== -1) {
        if (checkInput(info) && checkInput(json)) {
            if (checkInput(user)) {
                id = newPaste(user, info + "<=Data=>" + json);
                res.send(id);
                appendIDList(id);
                console.log("[+] " + id);
            } else {
                id = newPasteSingular(info + "<=Data=>" + json);
                res.send(id);
                appendIDList(id);
                console.log("[+] " + id);
            }
        }
    } else if (cmd.indexOf("REMOVE") !== -1) {
        res.send("Removed!");
        if (checkInput(user)) {
            removePaste(user, id);
        } else {
            removePasteSingular(id);
        }
        removeIDList(id);
        console.log("[-] " + id);
    } else if (cmd.indexOf("EDIT") !== -1) {
        if (checkInput(info) && checkInput(json)) {
            res.send("Edited!");
            editPaste(user, data, id);
        }
    }
});

app.get('*', function (req, res) {
    var route = req.url.toString().substring(1, req.url.toString().length);
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    if (route.length == 8) {
        for (var i = 0; i < route.length; i++) {
            if (possible.indexOf(route.charAt(i)) == -1) {
                res.send("Error.");
                return;
            }
        }
        var id = getPaste(route);
        res.send(id);
    } else if (route.indexOf("get/") !== -1) {
        route = route.substring(4, route.toString().length);
        var user = req.body.user || req.get("user") || route;
        if (fs.existsSync(__dirname + "/pastes/players/" + user)) {
            res.send(fs.readdirSync(__dirname + "/pastes/players/" + user, 'utf8'));
        } else res.send("Error!");
    } else if (route.indexOf("get") !== -1) {
        if (fs.existsSync(__dirname + "/pastes/files/")) {
            res.send(fs.readdirSync(__dirname + "/pastes/files/", 'utf8'));
        } else res.send("Error!");
    } else {
        res.send(usedIDs.length + "");
    }
});

function newPaste(user, data) {
    var id = newPasteID();
    var rootDir = __dirname + '/pastes/players';
    var playerDir = __dirname + '/pastes/players/' + user;
    var fileDir = __dirname + '/pastes/files';
    if (!fs.existsSync(fileDir)) {
        fs.mkdirSync(fileDir);
    }
    fs.writeFile(fileDir + '/' + id + '.txt', data, 'utf8', function (err) {
        if (err) return err;
    });
    if (!fs.existsSync(rootDir)) {
        fs.mkdirSync(rootDir);
    }
    if (!fs.existsSync(playerDir)) {
        fs.mkdirSync(playerDir);
    }
    fs.writeFile(playerDir + "/" + id + '.txt', "OwO", 'utf8', function (err) {
        if (err) return err;
    });
    return id;
}

function newPasteSingular(data) {
    var id = newPasteID();
    var fileDir = __dirname + '/pastes/files/';
    if (!fs.existsSync(fileDir)) {
        fs.mkdirSync(fileDir);
    }
    fs.writeFile(fileDir + '/' + id + '.txt', data, 'utf8', function (err) {
        if (err) return err;
    });
    return id;
}

function removePaste(user, id) {
    var playerDir = __dirname + '/pastes/players/' + user;
    var fileDir = __dirname + '/pastes/files/';
    if (!fs.existsSync(fileDir)) {
        fs.mkdirSync(fileDir);
    }
    if (fs.existsSync(fileDir + "/" + id + ".txt")) {
        fs.unlinkSync(fileDir + "/" + id + ".txt", 'utf8');
    }
    if (fs.existsSync(playerDir + "/" + id + ".txt")) {
        fs.unlinkSync(playerDir + "/" + id + ".txt", 'utf8');
    }
    if (fs.readdirSync(playerDir).length == 0) {
        fs.rmdirSync(playerDir);
    }
}

function removePasteSingular(id) {
    var fileDir = __dirname + '/pastes/files/';
    if (!fs.existsSync(fileDir)) {
        fs.mkdirSync(fileDir);
    }
    if (fs.existsSync(fileDir + "/" + id + ".txt")) {
        fs.unlinkSync(fileDir + "/" + id + ".txt", 'utf8');
    }
}

function editPaste(user, data, id) {
    var playerDir = __dirname + '/pastes/players/' + user;
    var fileDir = __dirname + '/pastes/files/';
    if (!fs.existsSync(fileDir)) {
        fs.mkdirSync(fileDir);
    }
    fs.writeFile(fileDir + '/' + id + '.txt', data, 'utf8', function (err) {
        if (err) return err;
    });
    if (!fs.existsSync(playerDir)) {
        fs.mkdirSync(playerDir);
    }
    fs.writeFile(playerDir + "/" + id + '.txt', data, 'utf8', function (err) {
        if (err) return err;
    });
    return id;
}

function newPasteID() {
    var id = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    var isValid = false;
    while (!isValid) {
        id = "";
        for (var i = 0; i < 8; i++) {
            id += possible.charAt(Math.floor(Math.random() * possible.length));
        }
        if (usedIDs.indexOf(id) == -1) isValid = true;
    }
    usedIDs.push(id);
    return id;
}

function getPaste(id) {
    return fs.readFileSync(__dirname + '/pastes/files/' + id + '.txt', 'utf8');
}

function loadIDList() {
    var ids = [];
    var id = fs.readFileSync(__dirname + "/backup.txt", 'utf8');
    ids = id.split("\n");
    return ids;
}

function saveIDList() {
    fs.truncateSync(__dirname + '/backup.txt', 0);
    var msg = "";
    msg += usedIDs[0];
    for (var i = 1; i < usedIDs.length; i++) {
        msg += "\n" + usedIDs[i];
    }
    fs.writeFileSync(__dirname + '/backup.txt', msg, 'utf8');
}

function appendIDList(id) {
    fs.appendFileSync(__dirname + '/backup.txt', "\n" + id, 'utf8', function (err) {
        if (err) return err;
    });
    var data = fs.readFileSync(__dirname + '/backup.txt');
    usedIDs = data.toString().split("\n");
}

function removeIDList(id) {
    var newArray = [];
    for (var i = 0; i < usedIDs.length; i++) {
        if (usedIDs[i] !== id) {
            newArray.push(usedIDs[i]);
        }
    }
    usedIDs = newArray;
    saveIDList();
}

function checkInput(data) {
    if (data != null) {
        return true;
    }
    return false;
}