update: changed implementation of zipcode related methods

packages/i18nify-go/country.go

@@ -14,22 +14,22 @@ type Country struct {
 }
 
 // GetCountryMetadata retrieves metadata information for the country.
-func (c Country) GetCountryMetadata() metadata.MetadataInformation {
+func (c *Country) GetCountryMetadata() metadata.MetadataInformation {
 	return metadata.GetMetadataInformation(c.Code)
 }
 
 // GetCountryPhoneNumber retrieves telephone number information for the country.
-func (c Country) GetCountryPhoneNumber() phonenumber.CountryTeleInformation {
+func (c *Country) GetCountryPhoneNumber() phonenumber.CountryTeleInformation {
 	return phonenumber.GetCountryTeleInformation(c.Code)
 }
 
 // GetCountrySubDivisions retrieves subdivision information for the country.
-func (c Country) GetCountrySubDivisions() subdivisions.CountrySubdivisions {
+func (c *Country) GetCountrySubDivisions() subdivisions.CountrySubdivisions {
 	return subdivisions.GetCountrySubdivisions(c.Code)
 }
 
 // GetCountryCurrency retrieves currency information for the country.
-func (c Country) GetCountryCurrency() []currency.CurrencyInformation {
+func (c *Country) GetCountryCurrency() []currency.CurrencyInformation {
 	// Retrieve metadata information for the country.
 	countryMetadata := c.GetCountryMetadata()
 
@@ -43,34 +43,25 @@ func (c Country) GetCountryCurrency() []currency.CurrencyInformation {
 }
 
 // GetStatesByZipCode retrieves the states with zipcode for the country.
-func (c Country) GetStatesByZipCode(zipcode string) []subdivisions.State {
-	subdivision := subdivisions.GetCountrySubdivisions(c.Code)
+func (c *Country) GetStatesByZipCode(zipcode string) []subdivisions.State {
+	subdivision := c.GetCountrySubDivisions()
 	return subdivision.GetStatesByZipCode(zipcode)
 }
 
 // GetCitiesByZipCode retrieves the cities with zipcode for the country.
-func (c Country) GetCitiesByZipCode(zipcode string) []subdivisions.City {
-	// Get the subdivision
-	subdivision := subdivisions.GetCountrySubdivisions(c.Code)
-	// Get list of all the states which have zipCode included.
-	states := subdivision.GetStatesByZipCode(zipcode)
-	var cities []subdivisions.City
-	// Get all cities with the zipCode from all the states.
-	for _, state := range states {
-		// Retrieve Cities with the zipCode from the state.
-		cities = append(cities, state.GetCitiesByZipCode(zipcode)...)
-	}
-	return cities
+func (c *Country) GetCitiesByZipCode(zipcode string) []subdivisions.City {
+	subdivision := c.GetCountrySubDivisions()
+	return subdivision.GetCitiesWithZipCode(zipcode)
 }
 
 // IsValidZipCode returns whether a pinCode is valid for the country or not.
-func (c Country) IsValidZipCode(zipcode string) bool {
+func (c *Country) IsValidZipCode(zipcode string) bool {
 	return len(c.GetStatesByZipCode(zipcode)) > 0
 }
 
 // NewCountry creates a new Country instance with the given country code.
 func NewCountry(code string) ICountry {
-	return Country{
+	return &Country{
 		Code: code,
 	}
 }

packages/i18nify-go/modules/country_subdivisions/country_subdivisions.go

@@ -17,6 +17,9 @@ import (
 //go:embed data
 var subDivJsonDir embed.FS
 
+// Cache to avoid duplicate reads for same countryCode
+var countrySubDivisionStore = make(map[string]CountrySubdivisions)
+
 // DataFile is the directory where JSON files containing country subdivision data are stored. "
 
 // UnmarshalCountrySubdivisions parses JSON data into a CountrySubdivisions struct.
@@ -33,8 +36,14 @@ func (r *CountrySubdivisions) Marshal() ([]byte, error) {
 
 // CountrySubdivisions contains information about country subdivisions.
 type CountrySubdivisions struct {
-	CountryName string           `json:"country_name"` // CountryName represents the name of the country.
-	States      map[string]State `json:"states"`       // States contains information about states or provinces within the country.
+	CountryName string            `json:"country_name"` // CountryName represents the name of the country.
+	States      map[string]State  `json:"states"`       // States contains information about states or provinces within the country.
+	ZipCodes    CountryZipCodeMap `json:"-"`            // CountryZipCodeMap contains information for reverse lookup on zipcodes within a country
+}
+type CountryZipCodeMap struct {
+	zipcodeToStates map[string][]State
+	zipcodeToCities map[string][]City
+	IsInitialized   bool
 }
 
 // GetCountryName returns the name of the country.
@@ -49,31 +58,24 @@ func (r *CountrySubdivisions) GetStates() map[string]State {
 
 // GetStatesByZipCode returns the list of states that have at least one city with the specified zip code.
 func (r *CountrySubdivisions) GetStatesByZipCode(code string) []State {
-	var states []State
-	for _, state := range r.States {
-		for _, city := range state.Cities {
-			for _, zipcode := range city.Zipcodes {
-				if zipcode == code {
-					states = append(states, state)
-					break
-				}
-			}
-		}
-	}
-	return states
+	return r.ZipCodes.zipcodeToStates[code]
 }
 
 // GetCitiesWithZipCode returns the list of cities with the specified zip code.
 func (r *CountrySubdivisions) GetCitiesWithZipCode(code string) []City {
-	var cities []City
-	for _, state := range r.States {
-		cities = append(cities, state.GetCitiesByZipCode(code)...)
-	}
-	return cities
+	return r.ZipCodes.zipcodeToCities[code]
+}
+
+// IsValidZipCode returns if the input zipcode is valid or not
+func (r *CountrySubdivisions) IsValidZipCode(code string) bool {
+	return len(r.ZipCodes.zipcodeToStates[code]) > 0
 }
 
 // GetCountrySubdivisions retrieves subdivision information for a specific country code.
 func GetCountrySubdivisions(code string) CountrySubdivisions {
+	if _, present := countrySubDivisionStore[code]; present {
+		return countrySubDivisionStore[code]
+	}
 	// Read JSON data file containing country subdivision information.
 	completePath := filepath.Join("data/", code+".json")
 	subDivJsonData, err := subDivJsonDir.ReadFile(completePath)
@@ -83,9 +85,37 @@ func GetCountrySubdivisions(code string) CountrySubdivisions {
 	}
 	// Unmarshal JSON data into CountrySubdivisions struct.
 	allSubDivData, _ := UnmarshalCountrySubdivisions(subDivJsonData)
+	// Initialise zipcode map to get faster retrieval for Cities and States
+	initializeZipCodeMap(&allSubDivData)
+	// Store calculated CountrySubDivisions into the cache
+	countrySubDivisionStore[code] = allSubDivData
 	return allSubDivData
 }
 
+// initializeZipCodeMap builds the zip code maps for the given CountrySubdivisions.
+func initializeZipCodeMap(subdivisions *CountrySubdivisions) {
+	// Ensure zip code maps are initialized only once.
+	if subdivisions.ZipCodes.IsInitialized {
+		return
+	}
+	var zipcodeToStates = make(map[string][]State)
+	var zipcodeToCities = make(map[string][]City)
+
+	// Iterate through all states and cities to populate the zip code maps.
+
+	for _, state := range subdivisions.States {
+		for _, city := range state.Cities {
+			for _, zipcode := range city.Zipcodes {
+				zipcodeToStates[zipcode] = append(zipcodeToStates[zipcode], state)
+				zipcodeToCities[zipcode] = append(zipcodeToCities[zipcode], city)
+			}
+		}
+	}
+	subdivisions.ZipCodes.zipcodeToStates = zipcodeToStates
+	subdivisions.ZipCodes.zipcodeToCities = zipcodeToCities
+	subdivisions.ZipCodes.IsInitialized = true
+}
+
 // NewCountrySubdivisions creates a new CountrySubdivisions instance.
 func NewCountrySubdivisions(countryName string, states map[string]State) *CountrySubdivisions {
 	return &CountrySubdivisions{
@@ -105,25 +135,6 @@ func (r *State) GetCities() []City {
 	return r.Cities
 }
 
-// IsValidZipCode return whether input zipcode is valid or not.
-func (r *State) IsValidZipCode(zipcode string) bool {
-	return len(r.GetCitiesByZipCode(zipcode)) > 0
-}
-
-// GetCitiesByZipCode returns the City based on the input code.
-func (r *State) GetCitiesByZipCode(code string) []City {
-	var cities []City
-	for _, city := range r.Cities {
-		for _, zipcode := range city.Zipcodes {
-			if zipcode == code {
-				cities = append(cities, city)
-				break
-			}
-		}
-	}
-	return cities
-}
-
 // GetName returns the name of the state.
 func (r *State) GetName() string {
 	return r.Name

packages/i18nify-go/modules/country_subdivisions/country_subdivisions_test.go

@@ -139,33 +139,26 @@ func TestGetCitiesWithZipCode(t *testing.T) {
 }
 
 func TestIsValidZipCode(t *testing.T) {
-	state := State{
-		Name: "Karnataka",
-		Cities: []City{
-			{Name: "Bengaluru", Timezone: "Asia/Kolkata", Zipcodes: []string{"560018", "560116"}},
-			{Name: "Mysore", Timezone: "Asia/Kolkata", Zipcodes: []string{"570001"}},
-		},
-	}
-
-	assert.True(t, state.IsValidZipCode("560116"))
-	assert.False(t, state.IsValidZipCode("999999"))
-}
-
-func TestGetCitiesByZipCode(t *testing.T) {
-	state := State{
-		Name: "Karnataka",
-		Cities: []City{
-			{Name: "Bengaluru", Timezone: "Asia/Kolkata", Zipcodes: []string{"560018", "560116"}},
-			{Name: "Mysore", Timezone: "Asia/Kolkata", Zipcodes: []string{"570001"}},
+	data := CountrySubdivisions{
+		CountryName: "India",
+		States: map[string]State{
+			"KA": {
+				Name: "Karnataka",
+				Cities: []City{
+					{Name: "Bengaluru", Timezone: "Asia/Kolkata", Zipcodes: []string{"560018", "560116"}},
+					{Name: "Mysore", Timezone: "Asia/Kolkata", Zipcodes: []string{"570001"}},
+				},
+			},
+			"MH": {
+				Name: "Maharashtra",
+				Cities: []City{
+					{Name: "Mumbai", Timezone: "Asia/Kolkata", Zipcodes: []string{"400001"}},
+					{Name: "Pune", Timezone: "Asia/Kolkata", Zipcodes: []string{"560116"}},
+				},
+			},
 		},
 	}
 
-	cities := state.GetCitiesByZipCode("560116")
-
-	assert.Equal(t, 1, len(cities))
-	assert.Equal(t, "Bengaluru", cities[0].GetName())
-
-	// Test with a zip code that does not exist
-	cities = state.GetCitiesByZipCode("999999")
-	assert.Equal(t, 0, len(cities))
+	assert.True(t, data.IsValidZipCode("400001"))
+	assert.False(t, data.IsValidZipCode("199901"))
 }