Design a logging library

Medium35 minFree, no account

Everyone gets the levels right. The marks are in what happens when the sink is slow.

The question

Design a logging library: levels, several destinations, structured fields, and configuration per module.

Logging must not block the caller, and must not lose everything when the destination is slow.

Functional

Levels: trace, debug, info, warn, error, fatal.
Multiple sinks, console, file, network, each with its own minimum level and format.
Structured key-value context, inherited by child loggers.
Per-module level configuration, changeable at runtime.

Non-functional

A disabled log call costs essentially nothing.
A slow sink must not block application threads.
Under overload, drop deliberately rather than growing without bound.

35:00Commit to an answer before you open the solution. Reading it first teaches you to recognise good answers, which is not the skill being tested.

Stuck?

0 of 3 hints taken

The worked solution

written by a person · not a grade

Score yourself

0 of 5 marked

Made a disabled call genuinely cheap and explained how25
Moved IO off the calling path20
Bounded buffer with a deliberate drop policy by level25
Sinks never throw into the caller; drops are counted20
Per-module configuration with inheritance10

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