authorize.go

package authorization

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"path/filepath"
)

//---------------------------------------------------------------------------------------

const (
	rolePermissionFile = "data/role_permission.json"
)

//---------------------------------------------------------------------------------------

var (
	fileReader = ioutil.ReadFile
)

//---------------------------------------------------------------------------------------

var rolePermissionMap map[string]map[Permission]bool

//---------------------------------------------------------------------------------------

func init() {
	log.Println("init(): initializing role permission map")
	absPath, _ := filepath.Abs(rolePermissionFile)
	// read file bytes
	bytes, err := fileReader(absPath)
	if err != nil {
		log.Fatalf("init(): Error reading role permission JSON content: %v", err)
	}

	// unmarshal bytes into map
	var result map[string][]int
	err = json.Unmarshal(bytes, &result)
	if err != nil {
		log.Fatalf("init(): Error unmarshalling role permission JSON content: %v", err)
	}

	// construct role permission map
	rolePermissionMap = make(map[string]map[Permission]bool)
	for k, v := range result {
		permissions := make(map[Permission]bool)
		for _, perm := range v {
			permissions[Permission(perm)] = true
		}
		rolePermissionMap[k] = permissions
	}
} // init

//---------------------------------------------------------------------------------------

// Authorize checks if given role has the permission
func Authorize(roleID string, perm Permission) bool {
	permissions, ok := rolePermissionMap[roleID]
	if !ok {
		return false
	}
	return permissions[perm]
} // Authorize