#122: Give Me Back My Monolith

Sponsored by DigitalOcean: pythonbytes.fm/digitalocean

Brian #1: Combining and separating dictionaries

• PEP 584 -- Add + and - operators to the built-in dict class.

  • Steven D'Aprano
  • Draft status, just created 1-March-2019

  • d1 + d2 would merge d2 into d1

    • like {**d1, **d2}
    • or on two lines

          d = d1.copy()
          d.update(d2)
      

  • of note, (d1 + d2) != (d2 + d1)

  • Currently no subtraction equivalent
• Guido’s preference of + over |
• Related, Why operators are useful - also by Guido

Michael #2: Why I Avoid Slack

• by Matthew Rocklin
• I avoid interacting on Slack, especially for technical conversations around open source software.
• Instead, I encourage colleagues to have technical and design conversations on GitHub, or some other system that is public, permanent, searchable, and cross-referenceable.
• Slack is fun but, internal real-time chat systems are, I think, bad for productivity generally, especially for public open source software maintenance.
• Prefer GitHub because I want to
  • Engage collaborators that aren’t on our Slack
  • Record the conversation in case participants change in the future.
  • Serve the silent majority of users who search the web for answers to their questions or bugs.
  • Encourage thoughtful discourse. Because GitHub is a permanent record it forces people to think more before they write.
  • Cross reference issues. Slack is siloed. It doesn’t allow people to cross reference people or conversations across Slacks

Brian #3: Hunting for Memory Leaks in Python applications

• Wai Chee Yau
• Conquering memory leaks and spikes in Python ML products at Zendesk.
• A quick tutorial of some useful memory tools
• The memory_profiler package and matplotlib to visualize memory spikes.
• Using muppy to heap dump at certain places in the code.
• objgraph to help memory profiling with object lineage.
• Some tips when memory leak/spike hunting:
  • strive for quick feedback
  • run memory intensive tasks in separate processes
  • debugger can add references to objects
  • watch out for packages that can be leaky
    • pandas? really?

Michael #4: Give Me Back My Monolith

• by Craig Kerstiens
• Feels like we’re starting to pass the peak of the hype cycle of microservices
• We’ve actually seen some migrations from micro-services back to a monolith.
• Here is a rundown of all the things that were simple that you now get to re-visit
• Setup went from intro chem to quantum mechanics
  • Onboarding a new engineering, at least for an initial environment would be done in the first day. As we ventured into micro-services onboarding time skyrocketed
• So long for understanding our systems
  • Back when we had monolithic apps if you had an error you had a clear stacktrace to see where it originated from and could jump right in and debug. Now we have a service that talks to another service, that queues something on a message bus, that another service processes, and then we have an error.
• If we can’t debug them, maybe we can test them
• All the trade-offs are for a good reason. Right?

Brian #5: Famous Laws Of Software Development

• Tim Sommer
• 13 “laws” of software development, including
  • Hofstadter’s Law: “It always takes longer than you expect, even when you take into account Hofstadter's Law.”
  • Conway’s Law: “Any piece of software reflects the organizational structure that produced it.”
  • The Peter Principle: “In a hierarchy, every employee tends to rise to his level of incompetence.”
  • Ninety-ninety rule: “The first 90% of the code takes 10% of the time. The remaining 10% takes the other 90% of the time”

Michael #6: Beer Garden Plugins

• A powerful plugin framework for converting your functions into composable, discoverable, production-ready services with minimal overhead.
• Beer Garden makes it easy to turn your functions into REST interfaces that are ready for production use, in a way that’s accessible to anyone that can write a function.
• Based on MongoDB, Rabbit MQ, & modern Python
• Nice docker-compose option too

Extras

Michael:

• Firefox Send
• Ethical ads on Python Bytes (and Talk Python)

Brian:

• T&C 69: The Pragmatic Programmer — Andy Hunt
  • not up yet, but will be before this episode is released

Jokes

• From Derrick Chambers

  “What do you call it when a python programmer refuses to implement custom objects? self deprivation! Sorry, that joke was really classless.”

• via pyjokes: I had a problem so I thought I'd use Java. Now I have a ProblemFactory.