PyVideo.org - javascript

Objects and classes in Python (and JavaScript)

2011-07-21T00:00:00+00:00

Summary

[EuroPython 2011] Jonathan Fine - 23 June 2011 in "Training Pizza Napoli"

Description

Python has a well-thought out system for classes. Beginners can use it without understanding it all. Experts can use it to produce code that is both elegant and powerful (such as models and class-based views in Django). Python classes can be used for many purposes.

This tutorial arises from the author's experience in using classes to solve problems, such as:

Add custom methods and attributes to objects that are, at root, just an integer
Construct dictionaries whose values are functions
Construct classes on-the-fly
Implement JavaScript object semantics in Python (advanced topic)

The outline syllabus is:

Review of the class statement in Python (and decorators)
Subclassing built-in types such as int and tuple
How to define classes without using a class statement
How to define a dispatch dictionary using a class statement
Metaclasses as syntactic sugar for class construction
Metaclasses to provide new class semantics
Review of JavaScript object semantics
Using Python classes to implement JavaScript object semantics

For Guido on the history of Python classes see:

This tutorial is for Intermediate or Advanced Python programmers. (Beginners will find it very hard going.) The aim of the course is to explain exactly what happens when a class in constructed, and to learn ways of using this knowledge.

PyHP and the art of dating girls

2011-07-18T00:00:00+00:00

Summary

[EuroPython 2011] Fabio Rotondo - 21 June 2011 in "Track Lasagne"

Description

This will be both technical and light talk, introducing these important subjects:

the new scripting language PyHP, a solution to create dynamic web pages using the Python scripting language server side, a-la PHP, but smarter.
the LiWE (Lightweight Web Environment) Web Framework, a new and robust web framework written in both JavaScript and Python that will help you creating amazing websites.
how this new amazing technologies can help you date girls (this will be the light and funny part of the talk)

Prerequisites:

Very basic knowledge of PHP
Basic Python
Basic / None JavaScript

Getting started with Plone CMS development - Part 1

2013-07-05T00:00:00+00:00

Getting started with Plone CMS development - Part 2

2013-07-05T00:00:00+00:00

Server side story

2013-07-04T00:00:00+00:00

Dash: Interactive Data Visualization Web Apps with no Javascript

2019-07-10T00:00:00+00:00

Description

Your data science or machine learning project probably won't just produce a written report. Instead, projects are increasingly expected to produce interactive tools to allow end-users to explore data and results with rich, interactive visualizations. Inevitably, this will be done in a web browser, meaning you'll need to add a quantitatively trained web developer to your team, or have your data scientists spend time learning HTML, Javascript and CSS. Dash, a project by the team that makes Plotly, solves some of these problems by allowing data scientists to build rich and interactive websites in pure python, with minimal knowledge of HTML and absolutely no Javascript.

At decisionLab, a London-based data science consultancy producing decision tools, we've embraced Dash to produce proof-of-concept models for our projects in alpha. Although we're not officially connected to the plotly/Dash project, by using the library daily across many projects, we've learned many lessons and what we feel are best practises we'd like to share, and hear feedback on!

This talk will give an overview of Dash, how it works and what it can be used for, before outlining some of the common problems that emerge when data scientists are let loose to produce web applications, and web developers have to work with the pydata ecosystem. The talk also covers effective working practises to start producing cool interactive statistical web applications, fast. We'll also identify some of the pitfalls of Dash, and how and when to make the decision to stop using Dash and start building a proper web application.

Slides: http://domweldon-europython-2019-dash.s3.eu- west-2.amazonaws.com/index.html

Full Stack Type Safety

2020-07-23T00:00:00+00:00

Description

Beyond PEP-484 – ensure type consistency between layers

The introduction of PEP-484 gave us an option to enforce the internal type consistency of our Python applications. Our web projects, however, consist of multiple layers, with the Python app taking the role of an HTTP backend. What options do we have to ensure consistency across our stack? In this talk, we will see some technologies that we can employ to enforce the contract between the layers of our stack. Especially between the frontend and backend. We will demo, how this can be achieved with REST/Swagger and with GraphQL. As both the Graphene library and the open API support for django-rest-framework are both a work-in-progress, we would check, what is possible, and what is still lacking. We will also discuss various approaches to the design: backend first, auto-generating backend from the spec, and TDD, with their advantages and disadvantages. The topic would be discussed on a simple web application. We would try to play some realistic scenarios, where a careless developer breaks the contract to see how such a mistake can be spotted in the CI phase of the development cycle. Basic knowledge of Django and JavaScript is required to understand the talk. Some familiarity with TypeScript and ReactJS would also be helpful. However, I plan to explain the code to the listeners that didn’t have prior exposure to these technologies.

The Joy of Creating Art with Code.

2020-07-23T00:00:00+00:00

Description

Art is everywhere and it’s beautiful. Unleash the creative artist inside you with the beauty of Generative Art. Learn how algorithms are used to create these aesthetic art forms, how motion and structures emit sounds and what toolkits are required to do so. This talk looks at Python as an artistic and visual programming language with the simplicity and beauty of generative art using Processing, PyCairo and webGL. The audience will see an evolution of generative art over the last 50 years, how autonomously these art forms are created using algorithms and how we can stimulate paints and other media. The talk will be showing how to create artworks inspired by geometric and mathematical patterns which also includes randomness with hands-on examples (Two such examples are added here: https://imgur.com/a/lycAYnj ).

HTMX + Flask: Modern Python Web Apps, Hold the JavaScript

2021-12-04T00:00:00+00:00

Description

See how to combine htmx for building dynamic, interactive web apps in 100% Flask and Python without the need for frontend frameworks like Vue.js and others.

Fanstatic zum Einbinden statischer Ressourcen - Was es kann und was es können sollte.

2012-11-01T00:00:00+00:00

Summary

Fanstatic ist ein einfaches und doch mächtiges Werkzeug zum Einbinden statischer Ressourcen in Webanwendungen. In diesem Vortrag werden die Grenzen von Fanstatic aufgezeigt und Lösungen für diese vorgeschlagen.

Die Autoren setzen Fanstatic in fast jedem Projekt ein. Doch immer wieder stolpern wir über Probleme wie das Einbinden von Stylesheets für spezielle IE- Versionen (Conditional Stylesheets) oder die fehlenden Möglichkeit, Stylesheets für den Druck zu spezifizieren. Auch wäre eine Integration mit z.B. CoffeeScript wünschenswert.

Echtzeit Browsergames

2012-10-30T00:00:00+00:00

Summary

Mit gevent und browserseitigem JavaScript können Mehrspieler Browsergames entwickelt werden, die Spielerinteraktionen in Echtzeit zulassen. Dieser Vortrag versucht Lust auf das Echtzeit Web zu machen und zeigt anhand eines konkreten Spieles (KODEX, http://kodexgame.com/) Lösungen für Entwicklung, Hosting und Vertrieb auf.

Der Vortrag beleuchtet neben den Implikationen des Realtime Web wie Caching, Scaling, Same-Origin-Policy und Cross-Origin-Resource-Sharing auch Strategien zur horizontalen Skalierbarkeit, oder: Wie löst man das C10K Problem?

Während NodeJS oft als die Lösung für Echtzeitanwendungen angepriesen wird, kommt hier auf der Serverseite gezielt Python mit gevent zum Einsatz.

Echtzeit Web-Apps mit Mushroom

2013-10-15T00:00:00+00:00

Summary

Mushroom ist ein einfach zu verwendendes Echtzeit-Web-Messaging-Framework, welches neben Browser-Push-Nachrichten auch Funktionen für die Interprozesskommunikation zur Verfügung stellt.

Dieser Vortrag versucht, Lust auf das Echtzeit-Web zu machen und beantwortet grundlegende Fragen zu Themen wie Skalierbarkeit und Deployment.

Geospatial three amigos: Python, Leaflet, and ElasticSearch

2017-04-07T00:00:00+00:00

Description

One of the many jobs we do at our company is custom spatial solutions. Over time we’ve narrowed down the stack of products that are best suited for their jobs. Crime maps, construction zone mapping, public routes, and real state, we’ve done it all using these three components and this talk shows you how can do it too.

Sviluppo lato client con Odoo

2017-04-07T00:00:00+00:00

Description

Odoo è un framework utilizzato prevalentemente per lo sviluppo di soluzioni business, dall’ambito all’ERP all’e-commerce. E’ famoso per essere estremamente malleabile e scritto interamente in Python. Linguaggio con il quale può essere facilmente personalizzato ed esteso. Ma lo sviluppo di componenti client-side si fa sempre più sentire (hey, siamo nel 2017, non lamentarti) ed è ormai necessario comprendere come arricchire i nostri moduli Odoo scritti in Python con qualche riga di codice JavaScript.

Going Isomorphic with Django and React

2018-04-21T00:00:00+00:00

Description

In web development, an isomorphic application is one whose code (in this case, JavaScript) can run both in the server (in this case, Django) and the client. In this talk we will understand how it works and why it can be useful in the daily life. This talk is for developers (both backenders and frontenders) who believe in “DRY” and will love to learn something new.

repo: https://github.com/nostalgiaz/django-react-ssr

in __on sabato 21 aprile at 18:30 **See schedule**

How to use Web-Sockets in Python

2018-04-21T00:00:00+00:00

Description

Modern web-apps require bi-directional communication, reacting not only to user actions but also to server events. This can be achieved elegantly using Web Sockets, a protocol standardized by W3C to be a default tool for full- duplex connections on the Web.

Although most of web-frameworks do not support Web Socket integration out of the box, Python has multiple options available making it a piece of cake. This talk showcases running Web Sockets with Python web-apps, starting from situations that can make a good use of it, and followed by an implementation with most practical frameworks: Tornado and Django Channels. We will explore a similar style but different underlying technologies of both, and finish with a live demo.

in __on sabato 21 aprile at 12:00 **See schedule**

Building real time applications with Django

2018-04-20T00:00:00+00:00

Description

Since the introduction of Channels, real time web has become much easier to work with in Django. It’s now possible to build real time applications with much less effort in managing the idiosyncrasies of the async programming and a lot of batteries are included. Starting with a brief introduction to Channels, we will see how to build a real time application, both on the Django and the frontend side and how easy it’s to start experimenting with it. The talk has a very hands-on approach, to allow the attendees to experiment with the proposed solution and approach and starting immediately building their own real time applications with Django.

in __on venerdì 20 aprile at 14:30 **See schedule**

Evolution or stagnation programming languages

2018-04-20T00:00:00+00:00

Description

Programming languages evolves with the need to the developers, but not all of them evolves at the same speed and sometimes some languages stays almost the same for decades. Is this a sign of stagnation? Is it possible to evolve a language without breaking retrocompatibility?

This talk will cover how Python and Javascript approached the problem in a radically different way, with their pro and cons and with the consequences on the community.

The main points of this talk are:

comparation of the new features in both languages
strategies used to port or run the code on different versions of the language
impact of the new features and tool on the respective developer’s communities

The intent is to start a constructive discussion about the retrocompatility in Python.

For this talk you don’t need to have a deep knowledge of Python or Javascript.

in __on Friday 20 April at 11:45 **See schedule**

Decoupling Django with Django REST (and a sprinkle of React)

2019-05-05T00:00:00+00:00

Description

Abstract

With the rise of JavaScript as the lingua-franca of the web and the steady growth of libraries like React, today’s web developers can build rich and well structured frontend experiences. Pair that with Django and Django REST framework and you get the perfect combination. But it’s not all bells and whistles. What challenges are we going to face when decoupling Django with Django REST? What are the best practices? How to structure such a project? In this talk I’ll guide Django developers (both beginners and intermediate) from 0 to structuring a decoupled Django project.

Description

The goal of this talk is to give Django developers an overview of a Django REST project, paired with React, as well as the tradeoffs of the decoupled approach. By the end of the talk the developer should be able to configure a new Django REST project and use a frontend library for interacting with the API.

1. Why and when to decouple Django

There are many ways for decoupling a Django application and each one depends on the use case. In this section we’ll outline what decoupling is, why decoupling is a great approach and why sometimes it is not the right thing to do. We’ll see what the challenges of such approach are and how to deal with authentication in a decoupled context.

2. Django REST fundamentals

Django REST framework is a Django application for exposing API endpoints from a Django project. It this section we’ll see the building blocks of a Django API app: the model, the serializer and the view. Models should not be a surprise for the audience, they come from Django. Serializers instead are provided by Django REST. We’ll also see how a Django REST view looks like and how to leverage both function based views and generic views within the project.

3. Setting up the frontend

The key for a truly decoupled experience is a frontend for consuming and interacting with the API. In this section we’ll see how to structure a Django REST project alongside with React. We will explore two approaches: fully decoupled frontend and mixed frontend.

4. A note on testing and closing words

In the context of a decoupled Django site we move from the typical Django tests to testing the API’s response instead. We will see how a simple API test looks like. And for the JavaScript frontend we’ll take a look at the current available tooling for functional testing.

Questions?

Feedback form: https://python.it/feedback-1735

in __on Sunday 5 May at 10:15 **See schedule**

Costruire un sito e-commerce con Odoo

2019-05-03T00:00:00+00:00

Description

In questa presentazione vedremo come costruire un sito e-commerce con Odoo in pochi passi. Parleremo brevemente dell’installazione del framework e della sua configurazione di base per arrivare alle modalità di personalizzazione.

Il focus sarà ovviamente la vendita online, ma mostreremo come un ambiente integrato come Odoo ci permette di gestire tutti i flussi legati all’e-commerce nella loro interezza. Partendo quindi dalla registrazione dei clienti fino alla spedizione del materiale.

Per quanto riguarda le personalizzazioni, parleremo dei vari market place dove è possibile trovare funzionalità aggiuntive, ma tratteremo anche le basi del SDK di Odoo che richiedono conoscenze sia di Python che di Javascript.

Feedback form: https://python.it/feedback-1762

in __on Friday 3 May at 18:00 **See schedule**

Mappe 🗺️ con GeoDjango 🌎, PostGIS 🐘 e Leaflet 🍃

2019-05-03T00:00:00+00:00

Description

Una mappa permette agli utenti di visualizzare e ricercare i dati in maniera spaziale ed è comune l’esigenza di aggiungerne una al proprio progetto web.

In questo talk vedremo come abbiamo integrato una mappa in un progetto web già in produzione usando GeoDjango , PostGIS e Leaflet ed eseguiremo una dimostrazione di integrazione da zero di una mappa in un progetto Django.

GeoDjango è un modulo incluso in Django che lo trasforma in un framework Web geografico di classe mondiale.

PostGIS è un estensione del database PostgreSQL che aggiunge il supporto per gli oggetti geografici consentendo di eseguire query spaziali.

Leaflet è la principale libreria JavaScript open source per mappe web interattive ottimizzate per dispositivi mobili.

Durante il primo meetup #PyRoma del 2019 abbiamo presentato una versione ridotta di questo talk limitandoci al solo caso d’uso. Info qui: www.paulox.net/2019/01/21/pyroma-2019/

Feedback form: https://python.it/feedback-1608

in __on Friday 3 May at 18:00 **See schedule**

Leaflet on steroids with Django

2022-06-03T00:00:00+00:00

Description

Leaflet on steroids with Django - PyCon Italia 2022

Django fornisce potenti strumenti per costruire applicazioni geospaziali. Ma cosa succede quando i dati da visualizzare diventano troppi, e gli strumenti di base non bastano più? Basato su un caso reale, in questo talk vedremo come rendere fruibile una mappa inizialmente lentissima da caricare. L’obiettivo del talk è quello di fornire spunti e strumenti per affrontare ottimizzazioni lato backend e frontend su Leaflet e Django, molto utili nel caso di grandi quantità di dati geospaziali. In particolare vedremo nel dettaglio:

Il problema, ovvero, una grande quantità di dati geospaziali da visualizzare in mappa, che prima dell’ottimizzazione sono praticamente inutilizzabili.

La soluzione lato backend. Vedremo l’impiego di:

filtri geospaziali intelligenti.
stream per servire grandi quantità di dati.

La soluzione lato frontend. Vedremo l’impiego di:

tecniche di ottimizzazione per il caricamento dinamico dei livelli Leaflet.
stream per il rendering progressivo dei dati geospaziali.
filtri intelligenti e relative librerie per ottimizzare le richieste verso il backend.
test unitari e funzionali per verificare tutte le feature della mappa.

Speaker: Valentino Gagliardi

Patti chiari, amicizia lunga. Disaccoppiamo lo sviluppo con test di contratto

2022-06-03T00:00:00+00:00

Description

Patti chiari amicizia lunga. Come disaccoppiamo lo sviluppo tramite i test di contratto - PyCon Italia 2022

Front-end, vi è mai capitato che nonostante vi siate messi d’accordo con il back-end l’endpoint non vi espone qualcosa? Noi abbiamo risolto utilizzando il Contract testing, vi mostrerò i vantaggi e alcuni casi reali di come scrivere un patto aiuta a rendere più semplice lo sviluppo per tutti. Quando sono entrato in 20tab l’azienda seguiva già le metodologie Lean e Agile ed era composta principalmente da sviluppatori Python/Django. Quando abbiamo deciso di disaccoppiare i servizi (back-end in Django e front-end in React JS) siamo andati incontro a difficoltà dovute ai differenti tempi di sviluppo o limiti tecnici. Come prima soluzione avevamo provato con alternare lo sviluppo dei due servizi prima iniziava il back-end, una volta completato partiva lo sviluppo front-end. Questo ci rendeva inefficienti a volte i dati che arrivavano al front-end erano insufficienti o eccessivi rispetto all’interfaccia che doveva costruire. Quindi abbiamo provato a dettagliare con maggior rigore tutti i requisiti tecnici necessari per partire in parallelo, ma lato front-end dovevamo sempre costruirci un server finto per procedere con lo sviluppo. In questo ci è venuto incontro il contract testing, entrambi i rappresentanti dei servizi si riuniscono prendono il design lo analizzano insieme e il front-end scrive un test di contratto dopo di che entrambi i servizi possono procedere con i rispettivi sviluppi in maniera svincolata tra di loro. Il front-end può sfruttare il pact-stub-server per scrivere test funzionali con cypress e per lavorare senza neanche tirare su il servizio back-end. Questo ha portato il front-end a riorganizzare il proprio template, ora abbiamo 3 tipi di test diversi, quelli unitari sui componenti, quelli funzionali con cypress e quelli di contratto con Pact JS. Tutti questi test tramite Docker vengono eseguiti nelle nostre pipeline e bloccano il nostro processo di deploy in caso di fallimento.

Slide:

Speaker: Daniele Pompa

Javascript for people who know Python

2011-03-11T00:00:00+00:00

Description

Javascript for people who know Python

Presented by Ian Bicking

Javascript as a diff on Python.

Abstract

You know Python. You should know Javascript. The two aren't so different, but this talk will explain exactly how they are different -- lists, dicts, objects, functions, loops and all the other details of Javascript described in terms of Python.

Saturday Afternoon Lightning Talks

2011-03-11T00:00:00+00:00

Summary

Saturday afternoon lightning talks

Description

Saturday Afternoon Lightning Talks

00:00 Eric Holscher - Read the Docs (readthedocs.org)
05:25 Nate Aune - DjangoZoom (DjangoZoom)
09:40 Paul Smith - Update on Japan
12:40 Phillip von Weitershausen - The English of Programming Languages (JavaScript)
18:15 Henrique Bastos - Community Bootstrap
24:00 Barry Warsaw - flufl.i18n library (https://launchpad.net/flufl.i18n)
31:20 Aron Griffis - Window Manglement with PyWO (http://code.google.com/p/pywo/)
35:00 Josiah Carlson - Over-Engineering for Dummies
40:35 Grace Law - Get the job you want