Distributor Authorization System Implementation in Golang

go.mod

@@ -0,0 +1,3 @@
+module Distributors
+
+go 1.22.0

main.go

@@ -0,0 +1,151 @@
+package main
+
+import (
+	"encoding/csv"
+	"fmt"
+	"log"
+	"os"
+	"strings"
+)
+
+type Distributors struct {
+	Include map[string]bool
+	Exclude map[string]bool
+	Parent  *Distributors
+}
+
+func MakeCorrect(loc string) string {
+	return strings.ToUpper(strings.TrimSpace(loc))
+}
+
+func getHairarchy(loc string) []string {
+	parts := strings.Split(loc, "-")
+	var heir []string
+	for i := len(parts); i > 0; i-- {
+		heir = append(heir, strings.Join(parts[len(parts)-i:], "-"))
+	}
+	return heir
+}
+
+func (d *Distributors) isIncluded(loc string) bool {
+	for _, part := range getHairarchy(loc) {
+		if d.Include[part] {
+			return true
+		}
+	}
+	return false
+}
+
+func (d *Distributors) isExcluded(loc string) bool {
+	for _, part := range getHairarchy(loc) {
+		if d.Exclude[part] {
+			return true
+		}
+	}
+	return false
+}
+
+func (d *Distributors) AddPermission(include, exclude []string) {
+	for _, loc := range include {
+		normLoc := MakeCorrect(loc)
+
+		if d.Parent != nil && d.Parent.isExcluded(normLoc) {
+			fmt.Printf("Error: cant add %s coz parent excluded it\n", loc)
+			continue
+		}
+
+		d.Include[normLoc] = true
+	}
+
+	for _, loc := range exclude {
+		d.Exclude[MakeCorrect(loc)] = true
+	}
+}
+
+func (d *Distributors) CanDistribute(loc string) bool {
+	normloc := MakeCorrect(loc)
+
+	if d.Parent != nil && !d.Parent.CanDistribute(loc) {
+		return false
+	}
+
+	if d.isExcluded(normloc) {
+		return false
+	}
+
+	if d.isIncluded(normloc) {
+		return true
+	}
+
+	if d.Parent == nil {
+		return false
+	}
+
+	return d.Parent.CanDistribute(loc)
+}
+
+func loadCSVData(filePath string) map[string]string {
+	file, err := os.Open(filePath)
+	if err != nil {
+		log.Fatal("failed to open csv:", err)
+	}
+	defer file.Close()
+
+	reader := csv.NewReader(file)
+	records, err := reader.ReadAll()
+	if err != nil {
+		log.Fatal("failed to read csv:", err)
+	}
+
+	cityMap := make(map[string]string)
+	for _, record := range records[1:] {
+		cityCode := MakeCorrect(record[0])
+		provCode := MakeCorrect(record[1])
+		countryCode := MakeCorrect(record[2])
+		cityName := record[3]
+		fullCode := fmt.Sprintf("%s-%s-%s", cityCode, provCode, countryCode)
+		cityMap[cityName] = fullCode
+	}
+	return cityMap
+}
+
+func main() {
+	cityMap := loadCSVData("cities.csv")
+
+	d1 := &Distributors{Include: make(map[string]bool), Exclude: make(map[string]bool)}
+	d1.AddPermission(
+		[]string{"IN", "CA"},
+		[]string{"KA-IN", "KLRAI-TN-IN"},
+	)
+
+	d2 := &Distributors{Include: make(map[string]bool), Exclude: make(map[string]bool), Parent: d1}
+	d2.AddPermission(
+		[]string{"IN"},
+		[]string{"TN-IN"},
+	)
+
+	d3 := &Distributors{Include: make(map[string]bool), Exclude: make(map[string]bool), Parent: d2}
+	d3.AddPermission(nil, nil)
+
+	testCities := []string{"Wellington", "Keelakarai", "Chennai", "Punch"}
+
+	for _, city := range testCities {
+		code, ok := cityMap[city]
+		if !ok {
+			fmt.Printf("City %s not found in csv :( \n", city)
+			continue
+		}
+
+		fmt.Printf("\nChecking for city: %s (%s)\n", city, code)
+		fmt.Printf("DISTRIBUTOR 1: %s\n", result(d1.CanDistribute(code)))
+		fmt.Printf("DISTRIBUTOR 2: %s\n", result(d2.CanDistribute(code)))
+		fmt.Printf("DISTRIBUTOR 3: %s\n", result(d3.CanDistribute(code)))
+	}
+}
+
+func result(can bool) string {
+	if can {
+		return "YES......... :)"
+	}
+	return "No.........  :("
+}