Getting Started with Flask in Windows 10
Creating Virtual Environment
This article assumes you are on windows 10 and using Python 3.10 from the Microsoft Store
Begin in the terminal typing the following.
python3 -m venv app
This should have created a folder called "app" with a virtual environment. VSCode will ask you if you want to activate the environment. If you are unable to activate the environment then type the following depneding on your terminal environment.
If Powershell, first change directory in the terminal to use the app folder (or whatver your project is called)
If command prompt (CMD), first change directory in the terminal to use the app folder (or whatver your project is called)
Be sure to copy and create a .gitignore file for your directory to not commit unnecessary files
After the environment has been activated install Flask
pip install Flask
Reminder, once all project dependancies have been installed to save your dependancies in a requirements.txt file.
pip freeze > requirements.txt
Be sure to update the file if you install additional dependencies
Testing if Flask Works
create a flaskr folder inside app. Then create a __init__.py file.
Inside this file copy the following code
import os from flask import Flask def create_app(test_config=None): # create and configure the app app = Flask(__name__, instance_relative_config=True) app.config.from_mapping( SECRET_KEY='dev', DATABASE=os.path.join(app.instance_path, 'flaskr.sqlite'), ) if test_config is None: # load the instance config, if it exists, when not testing app.config.from_pyfile('config.py', silent=True) else: # load the test config if passed in app.config.from_mapping(test_config) # ensure the instance folder exists try: os.makedirs(app.instance_path) except OSError: pass # a simple page that says hello @app.route('/') def hello(): return 'Hello, World!' return app
Once you've copied the code then run the following command in terminal. Once again ensuring your environment is activated. Replace flaskr with whatever you named your flask application folder
flask --app flaskr --debug run
You should see the following
* Serving Flask app 'flaskr' * Debug mode: on WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead. * Running on http://127.0.0.1:5000 Press CTRL+C to quit * Restarting with stat * Debugger is active! * Debugger PIN: 353-076-785
If you do, ctrl click the web address or copy the address into your browser. You should see a webpage that says hello world. You are now ready for the next step.
Adding HTML and CSS With Bootstrap
Inside flaskr lets create a templates folder to house our HMTL and a static folder for our CSS. Inside templates let's create an index.html for our homepage.
Finally let's update our init.py file to serve up this HTML. Amend the top import statement to include render templates and update the home function to serve the file.
from flask import Flask, render_template @app.route("/") def home(): return render_template('index.html')
Your home page should now include some styled bootstrapped card. Now let's play around with Bootstrap and Python to create a homepage for our site.
Create a .gitignore with the following code
# Created by https://www.toptal.com/developers/gitignore/api/flask # Edit at https://www.toptal.com/developers/gitignore?templates=flask ### Flask ### instance/* !instance/.gitignore .webassets-cache .env ### Flask.Python Stack ### # Byte-compiled / optimized / DLL files __pycache__/ *.py[cod] *$py.class # C extensions *.so # Distribution / packaging .Python build/ develop-eggs/ dist/ downloads/ eggs/ .eggs/ lib/ lib64/ parts/ sdist/ var/ wheels/ share/python-wheels/ *.egg-info/ .installed.cfg *.egg MANIFEST # PyInstaller # Usually these files are written by a python script from a template # before PyInstaller builds the exe, so as to inject date/other infos into it. *.manifest *.spec # Installer logs pip-log.txt pip-delete-this-directory.txt # Unit test / coverage reports htmlcov/ .tox/ .nox/ .coverage .coverage.* .cache nosetests.xml coverage.xml *.cover *.py,cover .hypothesis/ .pytest_cache/ cover/ # Translations *.mo *.pot # Django stuff: *.log local_settings.py db.sqlite3 db.sqlite3-journal # Flask stuff: instance/ # Scrapy stuff: .scrapy # Sphinx documentation docs/_build/ # PyBuilder .pybuilder/ target/ # Jupyter Notebook .ipynb_checkpoints # IPython profile_default/ ipython_config.py # pyenv # For a library or package, you might want to ignore these files since the code is # intended to run in multiple environments; otherwise, check them in: # .python-version # pipenv # According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control. # However, in case of collaboration, if having platform-specific dependencies or dependencies # having no cross-platform support, pipenv may install dependencies that don't work, or not # install all needed dependencies. #Pipfile.lock # poetry # Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control. # This is especially recommended for binary packages to ensure reproducibility, and is more # commonly ignored for libraries. # https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control #poetry.lock # pdm # Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control. #pdm.lock # pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it # in version control. # https://pdm.fming.dev/#use-with-ide .pdm.toml # PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm __pypackages__/ # Celery stuff celerybeat-schedule celerybeat.pid # SageMath parsed files *.sage.py # Environments .venv env/ venv/ ENV/ env.bak/ venv.bak/ # Spyder project settings .spyderproject .spyproject # Rope project settings .ropeproject # mkdocs documentation /site # mypy .mypy_cache/ .dmypy.json dmypy.json # Pyre type checker .pyre/ # pytype static type analyzer .pytype/ # Cython debug symbols cython_debug/ # PyCharm # JetBrains specific template is maintained in a separate JetBrains.gitignore that can # be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore # and can be added to the global gitignore or merged into this file. For a more nuclear # option (not recommended) you can uncomment the following to ignore the entire idea folder. #.idea/ # End of https://www.toptal.com/developers/gitignore/api/flask