hmetrics

This is Heroku's Go-specific language metrics, as a standalone package.

Heroku's support is inside an organization-internal base dumping-ground repo, which pulls in quite a few dependencies and is not a stable interface.

This package reproduces the core functionality of github.com/heroku/x/hmetrics in a more usable API and without all the other dependencies.

This package uses semantic versioning.
Note that Go only supports the most recent two minor versions of the language; for the purposes of semver, we do not consider it a breaking change to add a dependency upon a language or standard library feature supported by all currently-supported releases of Go.

We do not support the silent on-init enabling method of hmetrics: all production code which might error should log what it's doing and we are designed to integrate with production logging.

This library does not panic, by policy, even when it probably should. If the Spawn() function returns a non-nil error then that's probably panic-worthy.

Usage

import (
    "log"

    "go.pennock.tech/hmetrics"
    )

func main() {
    // This depends upon your logging library, etc.
    msg, cancel, err := hmetrics.Spawn(func(e error) {
        log.Printf("hmetrics error: %s", e)
        })
    if err != nil {
        // if environment variable not found or empty, that's not an error,
        // this is something which means we expected to log but never will
        // be able to.
        panic(err)
    }
    if cancel != nil {
        defer cancel()
    }
    log.Print(msg) // for warm fuzzy feelings that stuff has started correctly

    // do your work
}

Bugs

None known at this time.

There are not enough tests.