#91 Will there be a PyBlazor?

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Brian #1: What makes the Python Cool

• Shankar Jha
• “some of the cool feature provided by Python”
• The Zen of Python: import this
• XKCD: import antigravity
• Swapping of two variable in one line: a, b = b, a
• Create a web server using one line: python -m http.server 8000
• collections
• itertools
• Looping with index: enumerate
• reverse a list: list(reversed(a_list))
• zip tricks
• list/set/dict comprehensions
• Modern dictionary
• pprint
• _ when in interactive REPL
• Lots of great external libraries

Michael #2: Django 2.1 released

• The release notes cover the smorgasbord of new features in detail, the model “view” permission is a highlight that many will appreciate.
• Django 2.0 has reached the end of mainstream support. The final minor bug fix release (which is also a security release), 2.0.8, was issued today.
• Features
  • model “view” feature: This allows giving users read-only access to models in the admin.
  • The new [ModelAdmin.delete_queryset()](https://docs.djangoproject.com/en/2.1/ref/contrib/admin/#django.contrib.admin.ModelAdmin.delete_queryset) method allows customizing the deletion process of the “delete selected objects” action.
  • You can now override the default admin site.
  • Lots of ORM features
  • Cache: The local-memory cache backend now uses a least-recently-used (LRU) culling strategy rather than a pseudo-random one.
  • Migrations: To support frozen environments, migrations may be loaded from .pyc files.
  • Lots more

Brian #3: Awesome Python Features Explained Using Harry Potter

• Anna-Lena Popkes
• Initial blog post
• 100 Days of code, with a Harry Potter universe bent.
• Up to day 18 so far.

Michael #4: Executing Encrypted Python with no Performance Penalty

• Deploying Python in production presents a large attack surface that allows a malicious user to modify or reverse engineer potentially sensitive business logic.
• This is worse in cases of distributed apps.
• Common techniques to protect code in production are binary signing, obfuscation, or encryption. But, these techniques typically assume that we are protecting either a single file (EXE), or a small set of files (EXE and DLLs).
• In Python signing is not an option and source code is wide open.
• requirements were threefold:
  1. Work with the reference implementation of Python,
  2. Provide strong protection of code against malicious and natural threats,
  3. Be performant both in execution time and in stored space
• This led to a pure Python solution using authenticated cryptography.
• Created a .pyce file that is encrypted and signed
• Customized import statement to load and decrypt them
• Implementation has no overhead in production. This is due to Python's in-memory bytecode cache.

Brian #5: icdiff and pytest-icdiff

• icdiff: “Improved colored diff”
  • Jeff Kaufman
• pytest-icdiff: “better error messages for assert equals in pytest”
  • Harry Percival

Michael #6: Will there be a PyBlazor?

• The .NET guys, and Steve Sanderson in particular, are undertaking an interesting project with WebAssembly.
• WebAssembly (abbreviated Wasm) is a binary instruction format for a stack-based virtual machine. Wasm is designed as a portable target for compilation of high-level languages like C/C++/Rust, enabling deployment on the web for client and server applications.
• Works in Firefox, Edge, Safari, and Chrome
• Their project, Blazor, has nearly the entire .NET runtime (AKA the CLR) running natively in the browser via WebAssembly.
• This is notable because the CLR is basically pure C code. What else is C code? Well, CPython!
• Includes Interpreted and AOT mode:
  • Ahead-of-time (AOT) compiled mode: In AOT mode, your application’s .NET assemblies are transformed to pure WebAssembly binaries at build time.
• Being able to run .NET in the browser is a good start, but it’s not enough. To be a productive app builder, you’ll need a coherent set of standard solutions to standard problems such as UI composition/reuse, state management, routing, unit testing, build optimization, and much more.
• Mozilla called for this to exist for Python, but sadly didn’t contribute or kick anything off at PyCon 2018: https://www.youtube.com/watch?v=ITksU31c1WY
• Gary Bernhardt’s Birth and Death of JavaScript video is required pre-reqs as well (asm.js).

Extras and personal info:

Michael:

• Building data-driven web apps course is being well received
• Guido van Rossum: Python 3 retrospective — Guido’s final presentation as BDFL