Golang : Normalize email to prevent multiple signups example
If your application allows the public to sign up, chances are your application will attract the "unkind" types and they will attempt to sign up multiple times with the same email address by mixing symbols, upper and lower cases and adding dots to make variants of the same email address.
To prevent this sort of multiple sign ups, you can try to normalize(canonicalize - treat them as the same) the email addresses by removing the unwanted cases, symbols,etc. Below is an example of how to normalize email address with govalidator.NormalizeEmail()
function.
At this moment, the NormalizeEmail()
function only supports gmail.com accounts. You might want to see the source code in govalidator
package to modify it for your own requirement.
package main
import (
"github.com/asaskevich/govalidator"
"log"
)
func main() {
email := "sammy+SPammer@gmail.com"
normalized, err := govalidator.NormalizeEmail(email)
if err != nil {
log.Fatal(err)
}
log.Println("Before : ", email)
log.Println("Normalized email : ", normalized)
}
Output :
NOTE : IF gmail, anything after + symbol will be removed
2015/08/11 14:43:28 Before : sammy+SPammer@gmail.com
2015/08/11 14:43:28 Normalized email : sammy@gmail.com
change to another domain name, the result will be different.
2015/08/11 14:51:18 Before : sammy+SPammer@somewhere.com
2015/08/11 14:51:18 Normalized email : sammy
+spammer
@somewhere.com
Reference :
By Adam Ng
IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.
Advertisement
Tutorials
+4.5k Golang : fmt.Println prints out empty data from struct
+7.7k Golang : Random integer with rand.Seed() within a given range
+32.9k Golang : Integer is between a range
+5.2k Linux/Unix : Commands that you need to be careful about
+6.3k Golang : Dealing with struct's private part
+3k Golang : PGX CopyFrom to insert rows into Postgres database
+7.6k Golang : Sort lines of text example
+32.4k Golang : Call a function after some delay(time.Sleep and Tick)
+5.6k Golang : Humanize and Titleize functions
+17.8k Golang : Get RGBA values of each image pixel
+20.7k Golang : How to run Golang application such as web server in the background or as daemon?
+4.7k Javascript : How to refresh page with JQuery ?