Resource management using bracket pattern in Go

resource.go

// package resource provides bracket pattern for
// resource management
package resource

import (
	"fmt"
	"mime/multipart"
	"net/http"
	"os"
)

func With[R any, T any](
	acquire func() (R, error),
	release func(R) error,
	fn func(R) (T, error),
) (T, error) {
	var zero T

	r, err := acquire()
	if err != nil {
		return zero, fmt.Errorf("failed to acquire resource: %w", err)
	}

	result, err := fn(r)
	if err != nil {
		releaseErr := release(r)
		if releaseErr != nil {
			return zero, fmt.Errorf("failed to process resource: %w: failed to release resource: %w", err, releaseErr)
		}

		return zero, fmt.Errorf("failed to process resource: %w", err)
	}

	releaseErr := release(r)
	if releaseErr != nil {
		return zero, fmt.Errorf("failed to release resource: %w", releaseErr)
	}

	return result, nil
}

func WithFile[T any](path string, fn func(*os.File) (T, error)) (T, error) {
	acquire := func() (*os.File, error) { return os.Open(path) }
	release := func(f *os.File) error { return f.Close() }

	return With(acquire, release, fn)
}

func WithMultipartFile[T any](
	r *http.Request,
	key string,
	fn func(multipart.File) (T, error),
) (T, error) {
	acquire := func() (multipart.File, error) {
		f, _, err := r.FormFile(key)
		return f, err
	}

	release := func(f multipart.File) error { return f.Close() }

	return With(acquire, release, fn)
}