Generate simple QRCode

qrcode.go

package main

import (
        qrcode "github.com/skip2/go-qrcode"
        "io/ioutil"
        "os"
)

func main() {
        /*
                The maximum capacity of a QR Code varies according to the content encoded and the error recovery level. The maximum capacity is 2,953 bytes, 4,296 alphanumeric characters, 7,089 numeric digits, or a combination of these.
        */

        data, err := ioutil.ReadAll(os.Stdin)
        if err != nil {
                panic(err)
        }
        var png []byte
        png, err = qrcode.Encode(string(data), qrcode.Medium, 256)
        if err != nil {
                panic(err)
        }
        _, err = os.Stdout.Write(png)
        if err != nil {
                panic(err)
        }
}