Node sqlite3 when to close db - javascript

I cannot figure out when to close a db in node-sqlite3, or really how to use the package in general. It seems if I run this, I get "no such table:rooms". Eventually after running it enough times, I might manage to make the table.
var sqlite3 = require('sqlite3').verbose();
class RoomManager{
constructor(options){
this.db = this._createDb();
this.table = "rooms";
this._createTable();
this.addRoom({
name : 'test3'
}).getRooms()
this.deleteRoom({
name : 'test3'
}).getRooms();
return this;
}
_createDb() {
return new sqlite3.Database('chat');
}
_createTable(){
this.db.run("CREATE TABLE IF NOT EXISTS " + this.table + " (name TEXT, size INT)");
return this;
}
addRoom(options){
this.db.run("INSERT INTO " + this.table + " (name, size) VALUES ($name, $size)", {
$name : options.name,
$size : options.size || 1000
});
return this;
}
getRooms(){
this.db.all("SELECT rowid, name, size FROM " + this.table, function(err, rows) {
rows.forEach(function (row) {
console.log(row.rowid + ": " + row.name + " - " + row.size);
});
});
return this;
}
getRoom(options){
if(options.name){
this.db.get("SELECT * FROM " + this.table + " WHERE name = $name", {
$name : options.name
}, function(err, row){
return row;
});
}
}
deleteRoom(options){
this.db.run("DELETE FROM " + this.table + " WHERE name = $name", {
$name : options.name
});
return this;
}
}
module.exports = RoomManager;


Your problem that Node is asynchronous. So, you must wait end of command by callback function. e.g.
this.db.run(query, params, function(err) {
if (err)
return console.log(err);
// do next query here
})
Sqlite module can control flow by db.serialize. Imho it's useless in common cases. Better use async module or promises for it.

Related

Remove the function after it being used for the first time

I have the simple SQL query builder that looks like this:
class QueryBuilder {
select(fields) {
this.query = "SELECT `" + fields.join("`, `") + "` ";
return this;
}
from(table) {
this.query += "FROM `" + table + "` ";
return this;
}
}
The problem is that it returns this so I'm able to do like:
const sql = builder.select("field1", "field2").from("table").select("I shouldn't be able to call select");
Is there any way to disable/remove the select function from Builder instance and autocomplete after calling it for the first time? Or to underscore that calling that function for the second time will cause an error.
Solution:
According to #Sohail answer, to make it works like that you just need to move from() from the QueryBuilder class and just return it as a field with the query as a new plain object:
class QueryBuilder {
static select(fields) {
this.query = "SELECT `" + fields.join("`, `") + "` ";
return {
query: this.query,
from
};
}
}
function from(table) {
this.query += "FROM `" + table + "` ";
return {
query: this.query,
where: function() {}
};
}

You could return the specific method instead of this, that could be called in chain after this method.
Example:
class QueryBuilder {
select(fields) {
this.query = "SELECT `" + fields.join("`, `") + "` ";
return {
from: this.from.bind(this)
};
}
from(table) {
this.query += "FROM `" + table + "` ";
return {
where : ""
};
}
}

You can try below modification:
select(fields) {
if(!this.query.includes("SELECT")){
this.query = "SELECT `" + fields.join("`, `") + "` ";
}
return this;
}

Unable to send dynamic invoice value to struts2 server

I am working on angularjs 1.6.5
I am using following code to send data of invoice page.
$scope.products = [{qty: 0, description: ' ', sellingPrice: 0.0, unitPrice: 0.0, total: 0.0}];
$scope.fproducts = [];
$scope.generateInvoice = function () {
console.log("generateInvoice");
console.log($scope.fproducts);
console.log("sub total " + $scope.subTotal + " ft " + $scope.finalTotal + " pamt " + $scope.paidAmount + " baldue " + $scope.balancedue);
$scope.bd1 = {
'subTotal': $scope.subTotal,
'total': $scope.finalTotal,
'TotalPaid': $scope.paidAmount,
'invDateStr': $filter('date')($scope.invoiceDate, "MM/dd/yyyy"),
};
if ($scope.fproducts.length > 0) {
$scope.fproducts.forEach((total, index) => {
Object.entries(total).forEach(([key, value]) => {
console.log(index + " " + key + " " + value);
$scope.bd1[`billProductList[${index}].${key}`] = value;
});
});
}
//commenting above for each and removing comment from below code is
// working properly but I want to send dynamic data with above code
/* $scope.bd1[`billProductList[0].id`] = 1;
$scope.bd1[`billProductList[0].description`] = 1;
$scope.bd1[`billProductList[0].discountPercent`] = 150;
$scope.bd1[`billProductList[0].qty`] = 10;
$scope.bd1[`billProductList[0].sellingPrice`] = 100;
$scope.bd1[`billProductList[0].unitPrice`] = 100;
$scope.bd1[`billProductList[0].total`] = 150;*/
$scope.bd1[`BillPaidDetailses[0].paymentMode`] = $scope.paymentMode;
$scope.bd1[`BillPaidDetailses[0].amount`] = $scope.paidAmount;
console.log($scope.bd1);
$http({
method: 'POST',
url: 'added-invoice',
data: $httpParamSerializerJQLike($scope.bd1),
headers: {'Content-Type': 'application/x-www-form-urlencoded'}
}).then(function successCallback(data, status, headers, config) {
if (data.data.st === 1) {
$scope.success = true;
window.location = 'bhome#!/show-tax';
} else if (data.data.st === 0) {
$scope.success = false;
$scope.failure = true;
} else if (data.data.st === -1) {
$scope.success = false;
$scope.failure = true;
}
}, function errorCallback(data, status, header, config) {
$scope.success = false;
$scope.failure = true;
});
}
Above code is not passing value to server side object.
its console.log value is
on modifying above data
/*if ($scope.fproducts.length > 0) {
$scope.fproducts.forEach((total, index) => {
Object.entries(total).forEach(([key, value]) => {
console.log(index + " " + key + " " + value);
$scope.bd1[`billProductList[${index}].${key}`] = value;
});
});
}*/
$scope.bd1[`billProductList[0].id`] = 1;
$scope.bd1[`billProductList[0].description`] = 1;
$scope.bd1[`billProductList[0].discountPercent`] = 150;
$scope.bd1[`billProductList[0].qty`] = 10;
$scope.bd1[`billProductList[0].sellingPrice`] = 100;
$scope.bd1[`billProductList[0].unitPrice`] = 100;
$scope.bd1[`billProductList[0].total`] = 150;
as this is passing value to server object
its console.log is
I want to run my code using dynamic value specified in if condition.
What is the problem I am unable to get it.
EDIT I am using server side struts2
my code is
public class BillNewAction extends ActionSupport implements ModelDriven<BillDetails> {
BillDetails bd = new BillDetails();
private List<BillDetails> billList = new ArrayList<BillDetails>();
public String insert() {
System.out.println("total " + bd.getTotal()
+ " subTotal " + bd.getSubTotal() + " paid "
+ bd.getTotalPaid()
+ " invoiceDate " + bd.getInvDateStr()
);
SimpleDateFormat formatter1 = new SimpleDateFormat("MM/dd/yyyy");
try {
bd.setInvoiceDate((new java.sql.Date(formatter1.parse(bd.getInvDateStr()).getTime())));
} catch (ParseException ex) {
Logger.getLogger(BillNewAction.class.getName()).log(Level.SEVERE, null, ex);
}
for (BillPaidDetails b : bd.getBillPaidDetailses()) {
System.out.println("type " + b.getPaymentMode() + " amount "
+ b.getAmount()
);
}
System.out.println("product size " + bd.getBillPrList().size());
for (BillProduct b : bd.getBillPrList()) {
System.out.println("id " + b.getId() + " desc "
+ b.getDescription() + " qty " + b.getQty()
+ " sp " + b.getSellingPrice() + " up "
+ b.getUnitPrice() + " " + b.getTotal()
);
}
}
}
public class BillDetails implements java.io.Serializable {
private Long billNo;
private Client client;
private BigDecimal subTotal;
private BigDecimal TotalAmount;//total price
private BigDecimal TotalPaid;//Amount paid for getting items
private BigDecimal vat;
private BigDecimal total;
private String invoiceNo;
private Date invoiceDate;
private String invDateStr;
private List<BillPaidDetails> BillPaidDetailses = new ArrayList<BillPaidDetails>();
private List<BillProduct> billPrList = new ArrayList<BillProduct>();
//getter and setter
}
I have to send data in $scope.bd1[billProductList[0].id] = 1; format to server
Assigning indivisual value passing the data to server but I have dynamic no of values so I am trying
if ($scope.fproducts.length > 0) {
$scope.fproducts.forEach((total, index) => {
Object.entries(total).forEach(([key, value]) => {
console.log(index + " " + key + " " + value);
$scope.bd1[billProductList[${index}].${key}] = value;
});
});
}
that is not working

Consider using the Struts JSON Plugin
The JSON plugin provides a json result type that serializes actions into JSON.
The content-type must be application/json
Action must have a public “setter” method for fields that must be populated.
Supported types for population are: Primitives (int,long…String), Date, List, Map, Primitive Arrays, other class, and Array of Other class.
Any object in JSON, that is to be populated inside a list, or a map, will be of type Map (mapping from properties to values), any whole number will be of type Long, any decimal number will be of type Double, and any array of type List.
Your actions can accept incoming JSON if they are in package which uses json interceptor or by adding reference to it.
This simplifies the AngularJS HTTP POST request:
$scope.bd1 = {
'subTotal': $scope.subTotal,
'total': $scope.finalTotal,
'TotalPaid': $scope.paidAmount,
'invDateStr': $scope.invoiceDate.toISOString(),
'billProductList': $scope.fproducts,
};
$http({
method: 'POST',
url: 'added-invoice',
data: $scope.bd1,
headers: {'Content-Type': 'application/json'}
}).then(function successCallback(response) {
var data = response.data;
if (data.st === 1) {
$scope.success = true;
window.location = 'bhome#!/show-tax';
} else if (data.st === 0) {
$scope.success = false;
$scope.failure = true;
} else if (data.data.st === -1) {
$scope.success = false;
$scope.failure = true;
}
}, function errorCallback(response) {
$scope.success = false;
$scope.failure = true;
});

$scope.bd1[billProductList[${index}].${key}] = value; you are overriding value on this line of code
$scope.bd1[billProductList[${index}${index2}].${key}] you can change shape of object as per you need
$scope.fproducts.forEach((total, index) => {
Object.entries(total).forEach(([key, value],index2) => {
console.log(index + " " + key + " " + value);
$scope.bd1[`billProductList[${index}${index2}].${key}`] = value;
});
})

That may be because console.log(index + " " + key + " " + value) is returning correct value as you are getting inside loop.
try to access the below piece of code, after assigning to $scope.bd1:
Object.entries(total).forEach(([key, value]) => {
$scope.bd1[`billProductList[${index}].${key}`] = value;
console.log($scope.bd1[`billProductList[${index}].${key}`]);
});
And I guess $scope.bd1 is not getting updated hence it is not passing value to server side object.

javascript If/Else Loop; async issue

Right now this section of code is passing along undefined to if(customerWaiting >0). It's an issue with async that I can't seem to figure out.
Based off the other threads I looked at, it's very basic and a newbie question, I just can't make it work.
I was seeing if you could find it for me
Edit 1:
the goal of the code is to see if there are customers in the firebase "customerWaiting" database, if there is then display the modal, if there is not then say there are no customers waiting
structure for database is
customerWaiting
-Automatically generated ID
-customer information
Here is the code
var customerWaiting;
var employeeWaiting;
var ref = firebase.database().ref();
$("#connectNextUser").click(function() {
{
ref.child("customerWaiting").on("value", function(snapshot) {
var customerWaiting = snapshot.numChildren();
console.log("There are " + snapshot.numChildren() + " customers waiting");
});
ref.child("employeeWaiting").on("value", function(snapshot) {
var employeeWaiting = snapshot.numChildren();
console.log("There are " + snapshot.numChildren() + " employees waiting");
});
}
if (customerWaiting > 0) {
$("#myModal").modal();
console.log("connect");
} else {
console.log("There are " + customerWaiting + " employees waiting");
console.log("no connect");
}
});

If I understand you correctly you want to do this:
var ref = firebase.database().ref();
$("#connectNextUser").click(function() {
// query how many customers are waiting
ref.child("customerWaiting").on("value", function(snapshot) {
// as soon as you have the result then get the numChildren
var customerWaiting = snapshot.numChildren();
console.log("There are " + snapshot.numChildren() + " customers waiting");
if (customerWaiting > 0) {
// show the modal if customerWaiting > 0
$("#myModal").modal();
console.log("connect");
} else {
console.log("There are " + customerWaiting + " employees waiting");
console.log("no connect");
}
});
});
If you want to use await/async then ref.child("customerWaiting").on("value", resolve) has to support Promises, or you need to convert it to one:
var ref = firebase.database().ref();
$("#connectNextUser").click(async function() {
var snapshot = await new Promise((resolve, reject) => {
ref.child("customerWaiting").on("value", resolve)
// you should also handle the error/reject case here.
})
var customerWaiting = snapshot.numChildren();
console.log("There are " + snapshot.numChildren() + " customers waiting");
if (customerWaiting > 0) {
$("#myModal").modal();
console.log("connect");
} else {
console.log("There are " + customerWaiting + " employees waiting");
console.log("no connect");
}
});

javascript league api combinedTick callback

async run(message, args) {
LolApi.init('censored', 'na');
LolApi.setRateLimit(10, 500);
var input = '';
args = args.toLowerCase();
LolApi.Summoner.getByName(args, function (err, summoner) {
if (!err) {
Name = summoner[args].name;
Name = Name.toLowerCase();
Id = summoner[Name].id;
Level = summoner[Name].summonerLevel;
input += "Name: " + summoner[Name].name + '\n' +
"Level: " + Level + "\n";
console.log(input);
//message.reply(input);
process.nextTick(LolApi.getLeagueData);
}
else {
message.reply('Error fam.');
}
});
setTimeout(function(){console.log('Waiting...')},2000);
LolApi.getLeagueData(Id,'NA', function (err, summoner) {
if (!err) {
Tier = summoner[Id][0].tier;
Division = summoner[Id][0].entries[0].division;
input += "Tier: " + Tier + '\n' +
"Division: " + Division;
message.reply(input);
} else {
console.log(Name);
console.log(err);
message.reply('Error Fam' + Id + "test");
}
});
}
When i run this code up get an error 404 running the second part. It gives me an saying combinedTickCallback but im not sure what this means because i am a noob. I use node.js if that helps with anything

Unit testing a function and simulating an event emitter response

I am currently writing some tests against the code shown below in node.js using mocha. I want to simulate the response from the event emitter 'check_user'. I have sinon.js but I can't get my mind in the right place to work out the best way to simulate the response.
Anyone able to offer some advice on how to go about this?
TgCustomCommand.contact = new Command("contact", "Will send you a users contact card to add to your contact list. Usage is .contact nick", function (input, callback) {
var payload = input;
//Switch our contact to payload.to as this is what our checkuser function looks at
//Check the command over
if (payload.command_args === false) {
payload.response = 'msg ' + payload.to + ' ' + this.description;
return callback(null, payload);
} else {
payload.return = payload.to;
payload.to = payload.command_args; //Set up ready for nick check
//Check the nick exists
emitter.emit('check_user', payload, function (err, result) {
if (err) return callback(err, null);
payload = input; //Reset our payload so we have correct payload.to
//Check how many users we returned
if (result.length === 0) { //Not in our contact list
payload.response = 'msg ' + payload.return + ' I do not have that person in my contact list!';
return callback(null, payload);
} else if (result.length === 1) {
payload.to = result[0].Nick;
payload.response = "send_contact " + payload.return + ' ' + result[0].Phone + ' ' + result[0].Nick + " _";
return callback(null, payload);
}
else {
//loop through our object and create a list of those returned
payload.response = "msg " + payload.return + " I know multiple people with a similar nick: ";
for (var i = 0; i < result.length; i++) {
log.debug(result[i].Nick);
payload.response = payload.response + result[i].Nick + " ";
}
return callback(null, payload);
}
});
}
;
});

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