stampiotic

A flyweight tool for checking stampfile freshness.

Installation

Install from source with

$ cargo install stampiotic

You can build optimised binaries using Nightly's build-std feature, saving around 200 KiB.

$ cargo +nightly build --release
    -Z build-std=std,panic_abort
    -Z build-std-features=panic_immediate_abort
    --target x86_64-unknown-linux-gnu

Why?

Spinning up a shell (or worse, a Python or Perl script) takes substantially longer than invoking a small binary, so why bother? Some containers might not even include a shell by default. stampiotic has exactly one dependency: libc.

stampiotic is a particularly useful tool for implementing a watchdog timer in Kubernetes. Legacy services can just touch a stampfile periodically, which can then be checked using stampiotic as a periodic Kubernetes health check.

Usage

$ stampiotic max-age stampfile [...]

e.g.

$ stampiotic 60s /run/foo/foo-server.stamp 60s
$ stampiotic '30 min' make.stamp
$ stampiotic 1d long-process-1.stamp long-process-2.stamp
File "long-process-2.stamp" is too old (12345s > 86400s)
$ echo $?
1

Max-age parsing

Durations are parsed by humantime.