#138: Will PyOxidizer weld shut one of Python's major gaps?

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Brian #1: flake8-comprehensions

• submitted by Florian Dahlitz
• I’m already using flake8, so adding this plugin is a nice idea.
• checks your code for some generator and comprehension questionable code.
  • C400 Unnecessary generator - rewrite as a list comprehension.
  • C401 Unnecessary generator - rewrite as a set comprehension.
  • C402 Unnecessary generator - rewrite as a dict comprehension.
  • C403 Unnecessary list comprehension - rewrite as a set comprehension.
  • C404 Unnecessary list comprehension - rewrite as a dict comprehension.
  • C405 Unnecessary (list/tuple) literal - rewrite as a set literal.
  • C406 Unnecessary (list/tuple) literal - rewrite as a dict literal.
  • C407 Unnecessary list comprehension - '[HTML_REMOVED]' can take a generator.
  • C408 Unnecessary (dict/list/tuple) call - rewrite as a literal.
  • C409 Unnecessary (list/tuple) passed to tuple() - (remove the outer call to tuple()/rewrite as a tuple literal).
  • C410 Unnecessary (list/tuple) passed to list() - (remove the outer call to list()/rewrite as a list literal).
  • C411 Unnecessary list call - remove the outer call to list().
• Example:
  • Rewrite list(f(x) for x in foo) as [f(x) for x in foo]
  • Rewrite set(f(x) for x in foo) as {f(x) for x in foo}
  • Rewrite dict((x, f(x)) for x in foo) as {x: f(x) for x in foo}

Michael #2: PyOxidizer (again)

• Michael’s assessment - There are three large and looming threats to Python. Lack of
  • A real mobile development story
  • GUI applications on desktop operating systems
  • Sharing your application with users (this is VERY far from deployment to servers)
• Cover PyOxidizer before but seems to have just rocketed off last couple of weeks.
• At their PyCon 2019 keynote talk, Russel Keith-Magee identified code distribution as a potential black swan - an existential threat for longevity - for Python.
  • “Python hasn't ever had a consistent story for how I give my code to someone else, especially if that someone else isn't a developer and just wants to use my application.”
• They announced the first release of PyOxidizer (project, documentation), an open source utility that aims to solve the Python application distribution problem!
• PyOxidizer's marquee feature is that it can produce a single file executable containing a fully-featured Python interpreter, its extensions, standard library, and your application's modules and resources.
• You can have a single .exe providing your application.
• Unlike other tools in this space which tend to be operating system specific, PyOxidizer works across platforms (currently Windows, macOS, and Linux - the most popular platforms for Python today).
• PyOxidizer loads everything from memory and there is no explicit I/O being performed. When you **import** a Python module, the bytecode for that module is being loaded from a memory address in the executable using zero-copy.
• This makes PyOxidizer executables faster to start and import - faster than a python executable itself!

Brian #3: Using changedir to avoid the need for src

• I’ve been experimenting with combining flit, pytest, tox, and coverage for new projects.
• And in doing so, ran across a cool feature of tox that I didn’t know about before, changedir.
• It’s a feature of tox to allow you to run tests in a different directory than the top level project directory.
  • tox changedir docs
  • tox and pytest and changedir
• I talk about this more in episode 80 of Test & Code.
  • As an example project I build yet another markdown converter using regular expressions.
  • This is funny to me, considering the recent cloudflare outage due to a single regular expression. https://blog.cloudflare.com/cloudflare-outage/
  • “Tragedy is what happens to me, comedy is what happens to you” - Mel Brooks approximate quote.

Michael #4: WebRTC and ORTC implementation for Python using asyncio

• Web Real-Time Communication (WebRTC) - WebRTC is a free, open project that provides browsers and mobile applications with Real-Time Communications (RTC) capabilities via simple APIs.
• Object Real-Time Communication (ORTC) - ORTC (Object Real-Time Communications) is an API allowing developers to build next generation real-time communication applications for web, mobile, or server environments.
• The API closely follows its Javascript counterpart while using pythonic constructs:
  • promises are replaced by coroutines
  • events are emitted using pyee.EventEmitter
• The main WebRTC and ORTC implementations are either built into web browsers, or come in the form of native code.
• In contrast, the aiortc implementation is fairly simple and readable.
  • Good starting point for programmers wishing to understand how WebRTC works or tinker with its internals.
  • Easy to create innovative products by leveraging the extensive modules available in the Python ecosystem.
  • For instance you can build a full server handling both signaling and data channels or apply computer vision algorithms to video frames using OpenCV.

Brian #5: Apprise - Push Notifications that work with just about every platform!

• listener suggestion
• cool shim project to allow multiple notification services in one app
• “Apprise allows you to send a notification to almost all of the most popular notification services available to us today such as: Telegram, Pushbullet, Slack, Twitter, etc.
  • One notification library to rule them all.
  • A common and intuitive notification syntax.
  • Supports the handling of images (to the notification services that will accept them).”
• supports
  • notification services such as discord, gitter, ifttt, mailgun, mattermost, MS teams, twitter, …
  • SMS notification through Twilio, Nexmo, AWS, D7
  • email notifications

Michael #6: Websauna web framework

• Websauna is a full stack Python web framework for building web services and back offices with admin interface and sign up process https://websauna.org
• "We have web applications 80% figured out. Websauna takes it up to 95%.”
• Built upon Python 3, Pyramid, and SQLAlchemy.
• When to use it?
  • Websauna is focused on Internet facing sites where you have a public or private sign up process and an administrative interface. Its sweet spots include custom business portals and software-as-a-service products which are too specialized for off-the-shelf solutions.
• Benefits
  • Focus on core business logic as Websauna provides basic website building blocks like sign up and sign in.
  • Low learning curve and friendly comprehensive documentation help novice developers
  • Emphasis is on meeting business requirements with reliable delivery times, responsiveness, consistency
  • Site operations is half the story. Websauna provides an automated deployment process and integrates with monitoring, security and other DevOps solutions.

Extras

Michael:

• Data driven Flask course is out!

Brian:

• Recent Test & Code episodes were solo because I’m in the middle of a work move and didn’t want to schedule interviews around a crazy work schedule. However, that should settle down in July and I can get back to getting great guests on the show. But I’m also having fun with solo topics, so I’ll keep that in the mix.
  • upshot: if I’ve contacted you or you me about being on the show and you haven’t heard from me lately, give me a nudge with a DM or email or something.

Jokes

• An SQL query goes into a bar, walks up to two tables and asks, 'Can I join you?'
• Not a joke, really, but along the lines of “comedy when it happens to you”.
  • Reset procedure for GE lightbulbs theregister.co.uk/2019/06/20/ge_lightblulb_reset