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

1. Use a centralizing sequential stamper. (NO, not a Singleton).

2. 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

• Timestamp proposed changes

• Build a Mapper

• What is wrong with software

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The most beautiful code, the most beautiful functions, and the most beautiful programs are sometimes not there at all.

Jon Bentley

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This article is part of the CodeSmell Series.