How to handle errors using Knex.js - error-handling

I am using nest.js with knex and try to make error handler for my application.
So I can update my data in database using this code:
const updatedProject = await this.knex('projects')
.update('name', body.name) // body.name id new name which come from frontend
.where('id', id) // id also come from frotend and I compare this id and id in database
.returning('*');
return updatedProject[0];
But if I try to update the project whith id which don't exist I have not any errors.
I try catch them by this way but this is didn't work
const updatedProject = await this.knex('projects')
.update('name', body.name)
.where('id', id)
.returning('*')
.catch((error) => console.error(error));
return updatedProject[0];
How can I create and catch error if reqest is wrong?

Related

How to wait until query is completed in BigQuery in Node.js

I have a large table (over 50GB).
And I'll make a new table using a query job.
The query result row is not required. I want to be able to wait until the job is completely finished.
const {BigQuery} = require('#google-cloud/bigquery');
const bigquery = new BigQuery();
async function run() {
const [job] = await bigquery.createQueryJob({
// Actually I'm going to use a complex query rather than a simple copy.
query: 'SELECT * FROM `myproject.mydataset.mytable',
destinationTable: {
...
}
});
// I want to wait until the destination table creation is completed.
// But getQueryResults() brings overflow.
const [result] = await job.getQueryResults();
// I'd like to do other things after the destination table is created.
...
}
run();
Like the code above I tried using getQueryResults but it gave JavaScript heap out of memory.
I also tried to use {maxResult:1} option for getQueryResults().
But it gave return before the destination table creation.
For Node.js BigQuery, is there any way to wait until the destination table creation is completed?
Maybe job.on('complete', ...) event can help you. See: https://cloud.google.com/nodejs/docs/reference/bigquery/latest/bigquery/job
You can do something like:
const [job] = await bigquery.createQueryJob(...);
await new Promise((resolve, reject) =>
job
.on('complete', resolve)
.on('error', reject)
);
job.removeAllListeners();

How can I use the same value as written in the Json during the same test execution in the testcafe

I have been trying to use the value from the JSON that I have got added successfully using fs.write() function,
There are two test cases in the same fixture, one to create an ID and 2nd to use that id. I can wrote the id successfully in the json file using fs.write() function and trying to use that id using importing json file like var myid=require('../../resources/id.json')
The json file storing correct id of the current execution but I get the id of first test execution in 2nd execution.
For example, id:1234 is stored during first test execution and id:4567 is stored in 2nd test execution. During 2nd test execution I need the id:4567 but I get 1234 this is weird, isn't it?
I use it like
t.typeText(ele, myid.orid)
my json file contains only id like {"orid":"4567"}
I am new to Javascript and Testcafe any help would really be appreciated
Write File class
const fs = require('fs')
const baseClass =require('../component/base')
class WriteIntoFile{
constructor(orderID){
const OID = {
orderid: orderID
}
const jsonString = JSON.stringify(OID)
fs.writeFile(`resources\id.json`, jsonString, err => {
if (err) {
console.log('Error writing file', err)
} else {
console.log('Successfully wrote file')
}
})
}
}
export default WriteIntoFile
I created 2 different classes in order to separate create & update operations and call the functions of create & update order in single fixture in test file
Create Order class
class CreateOrder{
----
----
----
async createNewOrder(){
//get text of created ordder and saved order id in to the json file
-----
-----
-----
const orId= await baseclass.getOrderId();
new WriteIntoFile(orId)
console.log(orId)
-----
-----
-----
}
}export default CreateOrder
Update Order class
var id=require('../../resources/id.json')
class UpdateOrder{
async searchOrderToUpdate(){
await t
***//Here, I get old order id that was saved during previous execution***
.typeText(baseClass.searchBox, id.orderid)
.wait(2500)
.click(baseClass.searchIcon)
.doubleClick(baseClass.orderAGgrid)
console.log(id.ordderid)
----
----
async updateOrder(){
this.searchOrderToUpdate()
.typeText(baseClass.phNo, '1234567890')
.click(baseClass.saveBtn)
}
}export default UpdateOrder
Test file
const newOrder = new CreateOrder();
const update = new UpdateOrder();
const role = Role(`siteurl`, async t => {
await t
login('id')
await t
.wait(1500)
},{preserveUrl:true})
test('Should be able to create an Order', async t=>{
await newOrder.createNewOrder();
});
test('Should be able to update an order', async t=>{
await update.updateOrder();
});
I'll reply to this, but you probably won't be happy with my answer, because I wouldn't go down this same path as you proposed in your code.
I can see a couple of problems. Some of them might not be problems right now, but in a month, you could struggle with this.
1/ You are creating separate test cases that are dependent on each other.
This is a problem because of these reasons:
what if Should be able to create an Order doesn't run? or what if it fails? then Should be able to update an order fails as well, and this information is useless, because it wasn't the update operation that failed, but the fact that you didn't meet all preconditions for the test case
how do you make sure Should be able to create an Order always runs before hould be able to update an order? There's no way! You can do it like this when one comes before the other and I think it will work, but in some time you decide to move one test somewhere else and you are in trouble and you'll spend hours debugging it. You have prepared a trap for yourself. I wrote this answer on this very topic, you can read it.
you can't run the tests in parallel
when I read your test file, there's no visible hint that the tests are dependent on each other. Therefore as a stranger to your code, I could easily mess things up because I have no way of knowing about it without going deeper in the code. This is a big trap for anyone who might come to your code after you. Don't do this to your colleagues.
2/ Working with files when all you need to do is pass a value around is too cumbersome.
I really don't see a reason why you need to same the id into a file. A slightly better approach (still violating 1/) could be:
const newOrder = new CreateOrder();
const update = new UpdateOrder();
// use a variable to pass the orderId around
// it's also visible that the tests are dependent on each other
let orderId = undefined;
const role = Role(`siteurl`, async t => {
// some steps, I omit this for better readability
}, {preserveUrl: true})
test('Should be able to create an Order', async t=>{
orderId = await newOrder.createNewOrder();
});
test('Should be able to update an order', async t=>{
await update.updateOrder(orderId);
});
Doing it like this also slightly remedies what I wrote in 1/, that is that it's not visible at first sight that the tests are dependent on each other. Now, this is a bit improved.
Some other approaches how you can pass data around are mentioned here and here.
Perhaps even a better approach is to use t.fixtureCtx object:
const newOrder = new CreateOrder();
const update = new UpdateOrder();
const role = Role(`siteurl`, async t => {
// some steps, I omit this for better readability
}, {preserveUrl:true})
test('Should be able to create an Order', async t=>{
t.fixtureCtx.orderId = await newOrder.createNewOrder();
});
test('Should be able to update an order', async t=>{
await update.updateOrder(t.fixtureCtx.orderId);
});
Again, I can at least see the tests are dependent on each other. That's already a big victory.
Now back to your question:
During 2nd test execution I need the id:4567 but I get 1234 this is weird, isn't it?
No, it's not weird. You required the file:
var id = require('../../resources/id.json')
and so it's loaded once and if you write into the file later, you won't read the new content unless you read the file again. require() is a function in Node to load modules, and it makes sense to load them once.
This demonstrates the problem:
const idFile = require('./id.json');
const fs = require('fs');
console.log(idFile); // { id: 5 }
const newId = {
'id': 7
};
fs.writeFileSync('id.json', JSON.stringify(newId));
// it's been loaded once, you won't get any other value here
console.log(idFile); // { id: 5 }
What you can do to solve the problem?
You can use fs.readFileSync():
const idFile = require('./id.json');
const fs = require('fs');
console.log(idFile); // { id: 5 }
const newId = {
'id': 7
};
fs.writeFileSync('id.json', JSON.stringify(newId));
// you need to read the file again and parse its content
const newContent = JSON.parse(fs.readFileSync('id.json'));
console.log(newContent); // { id: 7 }
And this is what I warned you against in the comment section. That this is too cumbersome, inefficient, because you write to a file and then read from the file just to get one value.
What you created is not very readable either:
const fs = require('fs')
const baseClass =require('../component/base')
class WriteIntoFile{
constructor(orderID){
const OID = {
orderid: orderID
}
const jsonString = JSON.stringify(OID)
fs.writeFile(`resources\id.json`, jsonString, err => {
if (err) {
console.log('Error writing file', err)
} else {
console.log('Successfully wrote file')
}
})
}
}
export default WriteIntoFile
All these operations for writing into a file are in a constructor, but a constructor is not the best place for all this. Ideally you have only variable assignments in it. I also don't see much reason for why you need to create a new class when you are doing only two operations that can easily fit on one line of code:
fs.writeFileSync('orderId.json', JSON.stringify({ orderid: orderId }));
Keep it as simple as possible. it's more readable like so than having to go to a separate file with the class and decypher what it does there.

Storing results of SQL Select query in a var node js

I'm looking for a way to store the results of this select query like a "rank" chart for a game but I'm not sure if what I'm encountering is an async issue or a data-type issue or something else entirely. Any thoughts?
var ranksVar = [];
db.all("select * from user", function(err, rows){
if(err) {
throw err;
} else {
setValue(rows);
}
});
function setValue(value) {
ranksVar = value;
console.log(ranksVar);
}
I've found out a useful post about using SQLite with NodeJS and it gives you the basic examples needed to understand how to use it. Here it is: SQLite NodeJS
In your case, look under the section data query.
Here the example code:
const sqlite3 = require('sqlite3').verbose();
// open the database
let db = new sqlite3.Database('./db/chinook.db');
let sql = `SELECT DISTINCT Name name FROM playlists
ORDER BY name`;
db.all(sql, [], (err, rows) => {
if (err) {
throw err;
}
rows.forEach((row) => {
console.log(row.name);
});
});
// close the database connection
db.close();
As you can see, the rows variable is (I guess) a special type created by the module. To get all data from it, you might want to iterate over it and push it into your array variable.
Cheers 😁 !
I figured out the issue. It was a data type/async issue, I was trying to print a string for an undefined array.
Went back a loop and used the JSON.stringify method to display the array objects correctly.

Using promises in Mongoose

I am new to the Promise method used to retrieve multiple database records at the same time and I want to rewrite my existing code to use promises
I have this piece of code in Express:
getController.getData = function(req,res, collection, pagerender) {
var id = req.params.id;
collection.find({}, function(err, docs){
if(err) res.json(err);
else res.render(pagerender, {data:docs, ADusername: req.session.user_id, id: req.params.id});
console.log(docs);
});
};
Now I want to use promises here, so I can do more queries to the database. Anyone know how I can get this done?
First, check if collection.find({}) returns a promise. If it does, then you can call your code like:
collection.find({}).
then(function(docs){
res.render(pagerender, {data:docs, ADusername: req.session.user_id, id: req.params.id});
})
.catch( function(err) {
res.json(err);
})
If you want more calls here, just create new DB call and add another .then block.
I suggest you read the documentation on promises, just to get a general feeling about them (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/then). You will also see how you can handle both success and rejection in the same function if you want.

Saving todo list items in the backend

I'm having difficult coming up with the best possible way of storing todo list items in the backend. I was told that storing array and object in the backend was not a good idea. I'm trying to clone a google keep inspired web app.
Some context: as soon as the user submits their todo list, it will make an axios call to the backend that will iterate through an array of todo list items and save them individually to the backend.
Which inspired me with this current set up.
CREATE TABLE TODO (
ID SERIAL PRIMARY KEY,
title VARCHAR,
user_id INTEGER REFERENCES users(ID));
CREATE TABLE TODO_ITEM (
ID SERIAL PRIMARY KEY,
item VARCHAR,
complete BOOLEAN,
todo_list_id INTEGER REFERENCES TODO(id));
My frontend call to the backend looks like this
toDoArray.map(ele => {
axios.post('users/postToDoListItems', {
item: ele,
complete: false,
todo_list_id: ?
})
})
axios.post('users/postToDoList', {
title: title,
toDoList: toDoList
})
}
The TODO_ITEM table I would like to to reference my TODO table so that when it's called to the frontend and grouped with the correct table.
With my current setup, is it possible to pass the reference (TODO)ID to TODO_ITEM table?
so aaaww i think you made some little mistakes i dont know how you query on your back-end but you must notice that before making your tables you must make a connection to your db soo i think it's not back to check this
or if you did it before plz complete your info about your problem , but the right thing for making queries is this :
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost',
user : 'me',
password : 'secret',
database : 'my_db'
});
connection.connect();
connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) {
if (error) throw error;
console.log('The solution is: ', results[0].solution);
});
connection.end();
and for query from front-end you should do this :
<< fron-end >>
axios.post('users/postToDoListItems', {
item: ele,
complete: false,
todo_list_id: 1
})
<< back-end >>
route : postToDoListItems
connection.query(`SET complete = ${req.body.complete} FROM todo WHERE id =${req.body.id}`, function (error, results, fields) {
if (error) throw error;
res.json({results,fields})
});