It’s getting harder and harder to pick a framework to develop web applications with. ExpressJS and Flask are two very popular frameworks, and sometimes deciding which to use can be particularly challenging—especially if you’re a beginner and wondering where to start. This post will help the beginner decide which framework is right for them.
What is a web framework?
A web framework is a component designed to support the development of web applications. Essentially, it is a tool representing a collection of libraries and modules that provide a web app developer with the necessary resources to easily develop web applications.
What is Flask?
Flask is a Python web microframework, officially launched in 2010 as an open source web development framework. Flask is designed to allow developers to build anything they want, from a blog to a commercial website. To get started with Flask, click here.
What is Express?
Express is a minimal and flexible Node.js web framework providing the core resources and tools required to build web applications. Using Express, you can easily build web servers that are maintainable, readable and flexible. To get started with Express, click here.
Advantages of Flask
Python framework: Python is considered an easier language to learn compared to other popular languages, so Flask could be a better beginning option.
Great documentation: The official documentation is very thorough, providing lots of details with well-written examples and clear tutorials.
Lots of resources available: Flask is arguably one of Python’s most popular web frameworks, with plenty of tutorials and libraries available to add to your apps.
Minimalistic: Flask is a lightweight framework with few dependencies. It takes just a few lines of Python to load Flask, and because it is modular, you can restrict the dependencies to suit your needs.
Simplicity: As a minimalistic framework, Flask provides the necessary tools to easily and quickly build a web app prototype after installation.
Easy Database Integration: Integration with database toolkits like SQLAlchemy, SQL databases like SQLite and MySQL, and NoSQL databases like DynamoDB and MongoDB is relatively easy.
Flexibility: Flask provides developers generous flexibility for developing their web applications.
Disadvantages of Flask
Flask is not async-friendly, as it was not designed to handle asynchronous programming. This is a problem because as a single-threaded framework, its web server can only handle one request at a time.
Thread locals and global variables used everywhere: The default way of creating applications with Flask makes applying reusable code difficult.
Setting up a large project: Setting up a large project with Flask is not easy. Blueprints are a useful tool to help developers, but they require some additional reading and may be a bit tricky for beginners.
Advantages of Express
JavaScript: JavaScript is an expressive language, and it is currently one of the most popular languages (if not the most popular).
Node framework: Node.js is an extremely fast framework built on Chrome’s V8 JavaScript engine. It is single-threaded, asynchronous and event-driven.
Easy to learn: Once you have a basic understanding of Node.js, you can move to Express. You will be creating express applications in no time.
Support for lots of plugins: Express takes advantage of NPM (Node Package Manager) to distribute and install countless third-party plugins, making it very easy to achieve what you want with Express.
Largest user base: Express is by far the most popular Node.js framework.
Minimalistic: Express is a lightweight, flexible framework with few dependencies. Express can be installed using a single line.
Great routing API: Express’ extremely powerful routing API allows developers to build routes for web apps, to use route parameters and query strings, and build a REST API.
Massive ecosystem of middleware: Express provides developers with various types of middleware, including application-level, router-level, error-handling, built-in, and third-party.
Disadvantages of Express
There are no strict standards with Express. Express considers itself to be a minimalistic, unopinionated framework—meaning it gives the developer the freedom to determine how their project will be organized. While it provides the flexibility and power to use multiple libraries and organize a project to your liking, the fact that there is no single recommended way of doing things can be a trap, especially if you’re a beginner.
Final thoughts
Flask and Express are two popular frameworks. The language you are most comfortable with may influence which one you choose, but I recommend you try out both frameworks. I guarantee there is a lot to gain from both.