Add method "IsValidContinent".

geoip.go

@@ -239,3 +239,31 @@ func LookupContinents(country string) []string {
 		return continents
 	}
 }
+
+func IsValidContinent(continent string) bool {
+	switch continent {
+	case "AF":
+		// Africa
+		fallthrough
+	case "AN":
+		// Antartica
+		fallthrough
+	case "AS":
+		// Asia
+		fallthrough
+	case "EU":
+		// Europe
+		fallthrough
+	case "NA":
+		// North America
+		fallthrough
+	case "SA":
+		// South America
+		fallthrough
+	case "OC":
+		// Oceania
+		return true
+	default:
+		return false
+	}
+}

geoip_test.go

@@ -200,3 +200,13 @@ func TestGeoLookupFromFile(t *testing.T) {
 
 	testGeoLookupReader(t, reader)
 }
+
+func TestIsValidContinent(t *testing.T) {
+	for country, continents := range ContinentMap {
+		for _, continent := range continents {
+			if !IsValidContinent(continent) {
+				t.Errorf("Continent %s of country %s is not valid", continent, country)
+			}
+		}
+	}
+}