go-ean is a simple utility library for calculating EAN checksum and validating EAN-8, EAN-13 and UPC numbers. This project is a fork of the project https://github.com/nicholassm/go-ean adopted for the new Go 1.11 Modules.
Import the package in the application code. For example
import "github.com/victorsmirnov/go-ean/ean"
When you build the project using go buid it will install the latest package version automatically
and update go.mod and go.sum files.
Example output from the go buid command:
$ go build main/*
go: finding github.com/victorsmirnov/go-ean/ean latest
If you do not use 1.11 Modules you can still install the package using go get command
go get github.com/victorsmirnov/go-ean/ean
To calculate a checksum use the ChecksumEan8, ChecksumEan13 or ChecksumUpc functions:
upcStr := "012345678905"
if c, err := ean.ChecksumUpc(upcStr); err != nil {
fmt.Printf("Checksum fail, error %+v\n", err)
} else {
fmt.Printf("UPC %s, checksum %d\n", upcStr, c)
// Prints "UPC 012345678905, checksum 5"
}
To check the validity of a string as EAN-8, EAN-13 or UPC use Valid:
valid = ean.Valid("012345678905")
fmt.Printf("General validation 629104150021, valid %t\n", valid)
// Prints "General validation 629104150021, valid true"
See examples for complete working application.
In the original library nicholassm/go-ean the checksum() function expected the ean string argument
to include the last check digit. In my version the string may not have the last digit.
(The MIT License)
Copyright (c) 2013 Nicholas Schultz-Møller Copyright (c) 2019 Victor Smirnov
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.