How to set `-ldflags` values for each target in Goreleaser?

Question

I need to set Os/Arch variable for each build target. My initial thought was to have a script that would calculate these variables and using hooks to run this script every target.

.goreleaser.yaml:

builds:
  hooks:
    pre:
      - sh variables.sh
  ldflags:
    - -s -w -X "main.goversion={{.Env.GOVERSION}}"
    - -s -w -X "main.commit={{.Env.GITCOMMIT}}"
    - -s -w -X "main.os={{.Env.GOOS}}"
    - -s -w -X "main.arch={{.Env.GOARCH}}"
    - -s -w -X "main.commit={{.Env.GITCOMMIT}}"
    - -s -w -X "main.date={{.Env.BUILDTIME}}"

variables.sh

#!/bin/bash

export GITCOMMIT=${GITCOMMIT:-$(git rev-parse --short HEAD 2> /dev/null || true)}
export BUILDTIME=${BUILDTIME:-$(date -u +"%Y-%m-%dT%H:%M:%SZ")}
export GOOS="${GOOS:-$(go env GOHOSTOS)}"
export GOARCH="${GOARCH:-$(go env GOHOSTARCH)}"
export GOVERSION=$(go version | awk '{print $3;}')

But as the variables are not defined anywhere in the config, so it seems it fails to recognize them, throwing:

release failed after 0.45s error=template: tmpl:1:31: executing "tmpl" at <.Env.GOVERSION>: map has no entry for key "GOVERSION"

Which makes sense. But now I am concerned how do I set target specific variables for each target?

Answer 1

Variables exported in those hooks will not leak to the builder itself.

You could, however, do something like:

source variables.sh
goreleaser release --rm-dist

and the variables should be available in the .Env map on templates.

PS: you don't need to set GOOS and GOARCH, GoReleaser does that for you.

PPS: build time and commit are available as native template variables/functions