JavaScript

#javascript #node #jest #testing #MongoDB

Avoiding recursion pitfalls: MongoDB nested query clause addition and removal

A case-study on where recursion can be useful for enterprise Node.js applications and how to avoid its common pitfalls like RangeError: Maximum call stack size exceeded. The full repository for this post is on GitHub: github.com/HugoDF/mongo-query-clause-modification We’ll ...

#node #Express #javascript

Read and parse POST/PATCH/PUT request JSON or form body with Express and no dependencies

When asked to handle data in a request body, developers who have used Express (the “Fast, unopinionated, minimalist web framework for Node.js”) before, reach for the body-parser library. What they might not know is that body-parser is a dependency of Express and its main JSON par ...

#node #javascript #Sequelize #productivity

Using ES6 classes for Sequelize 4 or 5 models

The ES2015 or ES6 specification introduced class to JavaScript. Libraries like React went from React.createClass to class MyComponent extends React.Component, ie went from rolling their own constructor to leveraging a language built-in to convey the programmer’s intent. For a Nod ...

#testing #jest #node #javascript #jest

Jest assert over single or specific argument/parameters with .toHaveBeenCalledWith and expect.anything()

With Jest it’s possible to assert of single or specific arguments/parameters of a mock function call with .toHaveBeenCalled/.toBeCalled and expect.anything(). The full example repository is at github.com/HugoDF/jest-specific-argument-assert, more specifically lines 17-66 i ...

#express #docker #javascript #node

An enterprise-style Node.js REST API setup with Docker Compose, Express and Postgres

The why and how of enterprise-style Node.js application. A setup that’s easy to test and extend using battle-hardened technologies like Express.js, Postgres and Docker Compose to run locally. Dive into the code on GitHub directly: github.com/HugoDF/express-postgres-starter. ...

#deployment #node #javascript #tooling #netlify #dokku

Deployment options: Netlify + Dokku on DigitalOcean or Hetzner Cloud vs now.sh, GitHub Pages, Heroku and AWS

Settling on a Netlify + Dokku on DigitalOcean (for US) or Hetzner Cloud (for EU) deployment stack for JavaScript and Node. Over the last few years I’ve never quite settled on a goto deployment strategy for my apps and projects. Technology-wise it has settled towards Vue or stati ...

#node #ava #Testing #javascript

JavaScript Object.defineProperty for a function: create mock object instances in Jest or AVA

This post goes through how to use Object.defineProperty to mock how constructors create methods, ie. non-enumerable properties that are functions. The gist of Object.defineProperty use with a function value boils down to: const obj = {} Object.defineProperty(obj, 'yes', { ...

#javascript #fetch

Pass cookies with axios or fetch requests

When sending requests from client-side JavaScript, by default cookies are not passed. By default, fetch won’t send or receive any cookies from the server, resulting in unauthenticated requests https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch Two JavaSc ...

#Express #node #jest #Testing #javascript

A testing guide for Express with request and response mocking/stubbing using Jest or sinon

To test an Express handler, it’s useful to know how to successfully mock/stub the request and response objects. The following examples will be written both using Jest and sinon (running in AVA). The rationale for this is the following. Jest is a very popular “all-in-one” testing ...

#Express #node #javascript #deployment

Node.js configuration management without config or dotenv

The config npm package is great (npmjs.com/package/config), but it encourages confusing and non-12-factor-app-compliant patterns. We’ll look at some of the patterns it encourages and why they’ll bring you struggles down the road as well a simple, single-file, no-dependency way to ...

A collection of 104 posts