Simple and easy to understand Flask framework installation tutorial

Flask Framework Installation Guide: Easy to master the installation steps, specific code examples are required

Introduction

Flask is a popular Python micro-framework, used For quickly building web applications. It's simple, flexible, and easy to get started with. This article will provide readers with an installation guide for the Flask framework, as well as supporting specific code examples, to help readers quickly master the installation and configuration process of Flask.

Directory

1. Preparation
2. Install Python and pip
3. Create a virtual environment
4. Install Flask
5. Create and run a simple Flask application
6. Summary
7. Preparation

Before you start installing Flask, make sure you have the following preparations:

• A computer running a Windows, macOS, or Linux operating system.
• A reliable internet connection.
• Administrator rights (for Windows users).
• Basic Python programming knowledge.

2. Installing Python and pip

Flask is a Python-based framework, so you need to install Python first. Please go to the official Python website (https://www.python.org/) to download the latest Python version and install it.

When installing Python, the system will automatically install a package management tool called pip. Modern versions of Python have pip installed by default, you can verify successful installation by entering pip --version on the command line.

3. Create a virtual environment

In order to avoid installing Flask in the global Python environment, we recommend using a virtual environment. A virtual environment can isolate dependency packages from the global environment, allowing multiple projects to use different dependency package versions.

First, make sure you are in the directory where you wish to create the virtual environment on the command line. Then create the virtual environment using the following command:

python -m venv myenv

where myenv is the name you gave the virtual environment. Please note that the python commands here may vary depending on your system and Python version. If you have both Python 2 and Python 3 installed on your system, you may need to use the python3 command.

After creating the virtual environment, you need to activate it. On Windows, use the following command:

myenvScriptsctivate

On macOS and Linux, use the following command:

source myenv/bin/activate

After successfully activating the virtual environment, the command line prompt will change to show the current environment for a virtual environment.

4. Install Flask

In a virtual environment, you can install Flask through the pip package management tool. Use the following command to install the latest version of Flask:

pip install flask

Flask depends on the two packages Jinja2 and Werkzeug. pip will automatically parse and install these dependent packages for you.

After the installation is complete, you can run the pip freeze command to check the installed packages to verify whether Flask is installed correctly.

5. Create and run a simple Flask application

Now, let us verify whether Flask is installed successfully through a simple example. Create a new Python file (e.g. app.py) and copy the following code into it:

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello():
    return 'Hello, Flask!'

if __name__ == '__main__':
    app.run()

This code creates a Flask application and defines a root route (/) for Returns a simple string.

Save and execute this Python file, then visit http://localhost:5000/ in the browser, you should be able to see a page that displays "Hello, Flask!". This means your Flask application is running successfully!

6. Summary

This article provides readers with an installation guide for the Flask framework to help readers easily master the installation and configuration steps of Flask. By creating a simple Flask application and successfully running it, readers can further delve into learning and developing more complex web applications.

I hope this article can provide some help to readers who are interested in Flask, allowing them to quickly get started and master this powerful framework.

Reference:

• Flask official documentation (https://flask.palletsprojects.com/)

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