go-maymoon/rootdir.go

package maymoon

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"
)
const (
	publicRootDirName string = "public_root"
	publicRootEnvName string = "PUBLIC_ROOT"
)

// RootDir returns the "root" directory.
//
// By default, where the "root" directory is depends which user it is running under.
//
// For example, on a Unix or Unix-like system such as Linux, with a user "joeblow" who has a home-directory at
// "/home/joeblow", RootDir might return "/home/joeblow/public_root".
//
// This can be overridden using the "PUBLIC_ROOT" environment variable.
// For example:
//
//	PUBLIC_ROOT=/path/to/public_root
//
// Example usage:
//
//	rootDir, err := maymoon.RootDir()
//	if nil != err {
//		return err
//	}
//	
//	fmt.Printf("The maymoon root-dir is at %q \n", rootDir)
//
// One usage for this function is to use the path it returns in HTTPHandler.
// For example:
//
//	rootDir, err := maymoon.RootDir()
//	if nil != err {
//		return err
//	}
//	
//	// ...
//	
//	var handler http.Handler = maymoon.HTTPHandler(rootDir)
func RootDir() (string, error) {

	{
		path := os.Getenv(publicRootEnvName)
		if "" != path {
/////////////////////// RETURN
			return path, nil
		}
	}

	var path string
	{
		homedir, err := os.UserHomeDir()
		if nil != err {
/////////////////////// RETURN
			return "", fmt.Errorf("problem getting user home-directory: %w", err)
		}

		path = filepath.Join(homedir, publicRootDirName)
		if "" == path {
/////////////////////// RETURN
			return "", errors.New("empty path")
		}
	}

	return path, nil
}