Code Smell 77 - Timestamps
Timestamps are widely used. They have a central issuing authority and do not go back, do they?
TL;DR: Don't use timestamps for sequence. Centralize and lock your issuer.
Problems
Bijection Fault.
Timestamp Collisions.
Timestamp precision.
Packet Disorders.
Bad Accidental Implementation (Timestamp) for an Essential Problem (Sequencing).
Solutions
Use a centralizing sequential stamper. (NO, not a Singleton).
If you need to model a sequence, model a sequence.
Sample Code
Wrong
# using time module
import time
# ts stores the time in seconds
ts1 = time.time()
ts2 = time.time() #might be the same!!
Right
numbers = range(1, 100000)
#create a sequence of numbers and use them with a hotspot
#or
sequence = nextNumber()
Detection
Timestamps are very popular on many languages and are ubiquitous.
We need to use them just to model... timestamps.
Tags
- Bijection
Conclusion
This smell was inspired by recent Ingenuity software fault.
If we don't follow our MAPPER rules and model sequences with time, we will face trouble.
Luckily, Ingenuity is a sophisticated Autonomous vehicle and has a robust fail-safe landing software.
This video describes the glitch
Relations
More info
The most beautiful code, the most beautiful functions, and the most beautiful programs are sometimes not there at all.
Jon Bentley
This article is part of the CodeSmell Series.