node.js – Page 21 – Tarik Billa

Sequelize – SQL Server – order by for association tables

January 3, 2024 by Tarik

From Sequelize offical docs: // Will order by an associated model’s created_at using an association object. (preferred method) [Subtask.associations.Task, ‘createdAt’, ‘DESC’], // Will order by a nested associated model’s created_at using association objects. (preferred method) [Subtask.associations.Task, Task.associations.Project, ‘createdAt’, ‘DESC’], By referring above syntax, Update your order option like below User.findById(uID, { include: [{ model: sequelize.models.userProfile … Read more

Models of concurrency in nodejs

January 3, 2024 by Tarik

It is useful to understand how node and V8 interact. Node handles waiting for I/O or timers from the operating system. When node wakes up from I/O or a timer, it generally has some JavaScript callbacks to invoke. When node runs these callbacks, control is passed into V8 until V8 returns back to node. So, … Read more

Using promises with streams in node.js

January 3, 2024 by Tarik

In this line stream.on(“end”, resolve(stream.dests[0].path)); you are executing resolve immediately, and the result of calling resolve (which will be undefined, because that’s what resolve returns) is used as the argument to stream.on – not what you want at all, right. .on‘s second argument needs to be a function, rather than the result of calling a … Read more

Converting from v8::Arguments to C++ Types

January 3, 2024 by Tarik

I know this is an older topic, but the way I tend to do this is as follows: Handle<Value> MethodName (const Arguments& args) { // get the param v8::String::Utf8Value param1(args[0]->ToString()); // convert it to string std::string foo = std::string(*param1); }

Get the Value of HTML Attributes Using Puppeteer

January 2, 2024 by Tarik

You can get attribute value with evaluate method. await page.evaluate(‘document.querySelector(“span.styleNumber”).getAttribute(“data-Color”)’) Second way $$eval method can also be used. Also attributes called as Array from variable const attr = await page.$$eval(“span.styleNumber”, el => el.map(x => x.getAttribute(“data-Color”))); Output will be [“Blue”, “Green”, “Red”] Your solution const styleNumbers = await page.$$(“span.styleNumber”); for( let styleNumber of styleNumbers ) { … Read more

How to make a UUID in DynamoDB?

January 2, 2024 by Tarik

express global middleware not being called

January 2, 2024 by Tarik

You should put your middleware before you use app.router. … app.use (function (req, res, next) { console.log (“inside middleware”); next(); }); … app.use(app.router);

How to catch an ENOENT with nodejs child_process.spawn?

January 2, 2024 by Tarik

As with many things in node, child processes can emit an error event. Add a listener for that and you will be able to catch it (no try-catch needed): var spawn = require(‘child_process’).spawn; var child = spawn(‘foo’); child.on(‘error’, function(err) { console.log(‘Oh noez, teh errurz: ‘ + err); });

How to install npm -g on offline server

January 2, 2024 by Tarik

try npmbox, it is the new name of npmzip which will allow you to install offline npm packages by one file

How to properly handle SIGINT with Express.js?

January 2, 2024 by Tarik

By catching the SIGINT handler, you are preventing the default behaviour, which is to quit the process. When you use Ctrl+C the second time, the process dies because server.close throws an uncaught exception. Just add a process.exit() to the end of your SIGINT handler to quit the process gracefully.