Testing Application Boundaries
...Software THAT WORKS!
Introduction
I'm the Chief Executive Developer at Level 12.
Level 12 is a web & database development firm that uses:
- solid engineering,
- proactive communication, and
- modern development practices
to make our customers really, really, happy.
Why it Matters to You
- Level 12 ... uses... modern development practices
- to make our customers really, really, happy
Net result: this works and is maintainable in the "real world"
Some Numbers
Biggest app:
- 6+ years
- 7,800 Python tests
- 350 JS tests
- 200+ DB tables
- 91% code coverage
Newer app: 1 year, 1,230 Python tests, 35+ DB tables, 95% coverage
I practice what I preach
Test Types Overview
- unit tests: isolate
- integration tests: multiple components
- functional tests: end to end testing
- acceptance tests: alias for functional tests?
- sytem tests: infrastructure dependent testing
- qa tests: let a human break it
Your definitions may differ.
Google's On To Something
Testing in Circles
Minimze the DMZ
Two Principles
- Promote IO & side effects to the edge (make the core bigger)
- Using dependency injection, mocks, etc. in the DMZ
Examples Today
- File access
- Date/time
- Web API
Database is Core
- The database is usually too important to the application to consider it in the DMZ
- Google allowed DB access for their "medium" tests
Bring on the Code
Code diffs: https://gist.github.com/rsyring
Thanks For Attending
Any questions? I'd appreciate feedback.