initial code import

validator.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"os"
+	"log"
+	"encoding/csv"
+	"fmt"
+	"strings"
+)
+
+func NewValidator(domain string, usersFile string) func(string) bool {
+
+	validUsers := make(map[string]bool)
+	emailSuffix := ""
+	if domain != "" {
+		emailSuffix = fmt.Sprintf("@%s", domain)
+	}
+
+	if usersFile != "" {
+		r, err := os.Open(usersFile)
+		if err != nil {
+			log.Fatalf("failed opening -authenticated-emails-file=%v, %s", usersFile, err.Error())
+		}
+		csv_reader := csv.NewReader(r)
+		csv_reader.Comma = ','
+		csv_reader.Comment = '#'
+		csv_reader.TrimLeadingSpace = true
+		records, err := csv_reader.ReadAll()
+		for _, r := range records {
+			validUsers[r[0]] = true
+		}
+	}
+
+	validator := func(email string) bool {
+		var valid bool
+		if emailSuffix != "" {
+			valid = strings.HasSuffix(email, emailSuffix)
+		}
+		if !valid {
+			_, valid = validUsers[email]
+		}
+		log.Printf("validating: is %s valid? %v", email, valid)
+		return valid
+	}
+	return validator
+}