Flask Workshop - PyCon 2015

(Presented at PyCon 2015)
Watch here: https://www.youtube.com/watch?v=DIcpEg77gdE

Flask is a web framework for Python based on Werkzeug, Jinja 2 and good intentions. It is considered a micro-framework, but don't get the "micro" part fool you; Flask can do everything others can do, many times in a simpler, leaner way. In this tutorial session we will build a web application together. Bring your laptop and your questions!

Transcript

1. Flask Workshop Miguel Grinberg @miguelgrinberg PyCon 2015
2. Who Am I? • I work for Rackspace as an OpenStack engineer. • I write about Flask, REST APIs, Robotics and more on my blog: http://blog.miguelgrinberg.com. • I am the author of a few open source Flask extensions: Flask-HTTPAuth, Flask-SocketIO, Flask-Migrate, etc. • I’m the author of the book Flask Web Development, and a few Flask training videos and webcasts, all for O’Reilly Media.
3. Agenda • Why Flask? • Setup • Example Application Demonstration • Let’s Build an Application ◦ Hello, Flask! ◦ Templates ◦ Web Forms ◦ User Sessions ◦ Error handling • What’s Next?
4. Why Flask? • Small, lightweight, straightforward. • Adapts easily to your way of thinking. • Plays well with third party Python packages. • Easy to build extensions (lots of extensions already available).
5. Setup • Python Interpreter ◦ Python 3.4 (recommended version) ◦ Python 2.7 + virtualenv • Git • Reference code on Github ◦ github.com/miguelgrinberg/flask-pycon2015.git ◦ Incremental versions are tagged v0.1, v0.2, and so on.
6. Demo!
7. Hello, Flask! • Create a project directory (or clone class project) • Create a virtual environment • Install Flask • A “Hello, World” application v0.1 • Add dynamic behavior v0.2 • Make application accessible to other computers v0.3
8. Templates • Why ◦ To separate logic from presentation. • How ◦ Create HTML templates v0.4 ◦ Create links between pages v0.5
9. Web Forms • Why ◦ To accept input from users • How ◦ Add a form to the application v0.6 ◦ The Post-Redirect-Get pattern v0.7 ◦ Using Flask-WTF and WTForms v0.8
10. Game Logic • Why ◦ Separation of concerns (again!) • How ◦ Add a module with the game logic v0.9 ◦ Implement the end of the game v0.10 ◦ Validate forms v0.11
11. User Sessions • Why ◦ To remember user state securely • How ◦ Store game state in the user session v0. 12
12. Error Handling • Why ◦ Because users are experts at finding bugs. • How ◦ Add error handler to the application v0. 13
13. What’s Next? • Databases • Authentication • HTML/CSS Styling • Structure for large applications • Application Programming Interfaces (APIs) • Rich client applications (Angular, Ember, React, etc.) • Unit Testing • Logging • Beyond HTTP: WebSocket • Deployment
14. @miguelgrinberg Thank You!