Summary

As software projects grow and change it can become difficult to keep track of all of the logical flows. By visualizing the interconnections of function definitions, classes, and their invocations you can speed up the time to comprehension for newcomers to a project, or help yourself remember what you worked on last month. In this episode Scott Rogowski shares his work on Code2Flow as a way to generate a call graph of your programs. He explains how it got started, how it works, and how you can start using it to understand your Python, Ruby, and PHP projects.

Announcements

• Hello and welcome to Podcast.__init__, the podcast about Python’s role in data and science.
• When you’re ready to launch your next app or want to try a project you hear about on the show, you’ll need somewhere to deploy it, so take a look at our friends over at Linode. With the launch of their managed Kubernetes platform it’s easy to get started with the next generation of deployment and scaling, powered by the battle tested Linode platform, including simple pricing, node balancers, 40Gbit networking, dedicated CPU and GPU instances, and worldwide data centers. Go to pythonpodcast.com/linode and get a $100 credit to try out a Kubernetes cluster of your own. And don’t forget to thank them for their continued support of this show!
• Subsurface Live is the cloud data lake conference, a virtual conference where data engineers, data scientists, data architects, and data analysts can gather and hear about cloud data lakes and the data ecosystem. Subsurface Live Winter 2022 includes keynote talks from Bill Inmon, the father of the data warehouse, Author of Deep Work Cal Newport, and several more from companies such as Dremio, AWS, dbt, and more. Subsurface will also have many breakout sessions featuring Pandas creator Wes McKinney, Apache Superset & Airflow creator Maxime Beauchemin, and engineers from Apple, Uber, Adobe, Bloomberg, and more. Meet other data professionals and learn about the data technologies and practices helping companies meet their current and future data needs. Register today at pythonpodcast.com/subsurface
• Your host as usual is Tobias Macey and today I’m interviewing Scott Rogowski about Code2Flow, a utility for generating "pretty good" call graphs for dynamic languages

Interview

• Introductions
• How did you get introduced to Python?
• Can you describe what Code2Flow is and the story behind it?
• What are some of the ways that a program’s call graph might be used?
• How does the visual representation generated by Code2Flow help with exploring the structure of a project?
  • What are some of the alternative approaches/tools that might be used to gain similar insights?
  • What do you see as the overlap in utility between Code2Flow and e.g. SourceGraph?
• Can you describe how the Code2Flow project is implemented?
  • How have the design and goals of the project changed since you first began working on it?
• Given that Code2Flow is implemented in Python, how have you managed the parsing/processing of the other languages that you support?
• Visualizing a complex program can quickly become very messy. How have you approached the layout of the output to enhance comprehension?
• What are some of the situations where Code2Flow will be unable to provide a full picture of a program’s call graph?
• What are some of the pieces of information that are unavailable due to the static analysis approach that you have taken?
• Can you describe the process of applying Code2Flow to a project?
  • Once the structure is on display, what are some next steps that an individual or team might take to analyze and act on the information?
• Given the static nature of the output, how might Code2Flow be incorporated in a CI/CD system to provide insight into the evolution of a projects structure?
• What are the most interesting, innovative, or unexpected ways that you have seen Code2Flow used?
• What are the most interesting, unexpected, or challenging lessons that you have learned while working on Code2Flow?
• When is Code2Flow the wrong choice?
• What do you have planned for the future of Code2Flow?

Keep In Touch

• Website
• scottrogowski on GitHub

Picks

• Tobias
  • Taking Vacation
  • Universal Studios, Florida
• Scott
  • Service work

Closing Announcements

• Thank you for listening! Don’t forget to check out our other show, the Data Engineering Podcast for the latest on modern data management.
• Visit the site to subscribe to the show, sign up for the mailing list, and read the show notes.
• If you’ve learned something or tried out a project from the show then tell us about it! Email hosts@podcastinit.com) with your story.
• To help other people find the show please leave a review on iTunes and tell your friends and co-workers

Links

• Code2Flow
• Colombia
• Mongita
• TI-83
• Ruby
• PHP
• AST == Abstract Syntax Tree
• Graphviz
• Pylint
• Robert Frost

The intro and outro music is from Requiem for a Fish The Freak Fandango Orchestra / CC BY-SA