Install Flask on your POWER web hosting plan

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KB0069074

Install Flask on your POWER web hosting plan


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Objective

You've subscribed to a Web POWER web hosting plan to deploy Python applications, and you want to deploy Flask on it.

This guide will explain how to do it.

Find out how to install Flask on your POWER web hosting plan.

Requirements

If you have just started to use your Web POWER web hosting plan, we suggest to have a look at our Getting started with a POWER web hosting plan guide before going further.

Instructions

Let's suppose you have the default configuration for Python hosting:

  • Runtime: Python 3.8
  • Entrypoint: app.py
  • DocumentRoot: www

To verify your configuration, you can use the Retrieve active configuration API endpoint.

To use Python WSGI frameworks, using virtualenv is the simplest choice.

Connect via SSH to your POWER web hosting and activate virtualenv:

cd www
virtualenv venv
source venv/bin/activate

Update pip:

pip install --upgrade pip

Install Flask.

pip install Flask

Create app.py with the following content, using the same trick to activate the virtualenv:

this_file = "venv/bin/activate_this.py"
exec(open(this_file).read(), {'__file__': this_file})

from flask import Flask
application = Flask(__name__)

@application.route('/')
def hello_world():
    return 'Hello, World!'

Then restart your instance and your Flask project will be online.

Flask

Terminal output:

~ $ cd www

~/www $ virtualenv venv
created virtual environment CPython3.8.7.final.0-64 in 1273ms
  creator CPython3Posix(dest=/home/powerlp/www/venv, clear=False, global=False)
  seeder FromAppData(download=False, pip=bundle, setuptools=bundle, wheel=bundle, via=copy, app_data_dir=/home/powerlp/.local/share/virtualenv)
    added seed packages: pip==20.2.2, setuptools==49.6.0, wheel==0.35.1
  activators BashActivator,CShellActivator,FishActivator,PowerShellActivator,PythonActivator,XonshActivator

~/www $ source venv/bin/activate

~/www $ pip install --upgrade pip
Collecting pip
  Using cached pip-21.0.1-py3-none-any.whl (1.5 MB)
Installing collected packages: pip
  Attempting uninstall: pip
    Found existing installation: pip 20.2.2
    Uninstalling pip-20.2.2:
      Successfully uninstalled pip-20.2.2
Successfully installed pip-21.0.1

~/www $ pip install Flask
Collecting Flask
  Using cached Flask-1.1.2-py2.py3-none-any.whl (94 kB)
Collecting itsdangerous>=0.24
  Using cached itsdangerous-1.1.0-py2.py3-none-any.whl (16 kB)
Collecting Werkzeug>=0.15
  Using cached Werkzeug-1.0.1-py2.py3-none-any.whl (298 kB)
Collecting click>=5.1
  Using cached click-7.1.2-py2.py3-none-any.whl (82 kB)
Collecting Jinja2>=2.10.1
  Using cached Jinja2-2.11.3-py2.py3-none-any.whl (125 kB)
Collecting MarkupSafe>=0.23
  Using cached MarkupSafe-1.1.1-cp38-cp38-manylinux2010_x86_64.whl (32 kB)
Installing collected packages: MarkupSafe, Werkzeug, Jinja2, itsdangerous, click, Flask
Successfully installed Flask-1.1.2 Jinja2-2.11.3 MarkupSafe-1.1.1 Werkzeug-1.0.1 click-7.1.2 itsdangerous-1.1.0

~/www $ mkdir -p tmp

~/www $ touch tmp/restart.txt

Go further

Join our community of users on https://community.ovh.com/en/.

Join our Discord on our web-hosting-power channel to discuss directly with the team and other users of this lab.

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