cloudflared-mirror/edgediscovery/protocol.go

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package edgediscovery
import (
"fmt"
"net"
"strconv"
"strings"
)
const (
protocolRecord = "protocol.argotunnel.com"
)
var (
errNoProtocolRecord = fmt.Errorf("No TXT record found for %s to determine connection protocol", protocolRecord)
)
func HTTP2Percentage() (int32, error) {
records, err := net.LookupTXT(protocolRecord)
if err != nil {
return 0, err
}
if len(records) == 0 {
return 0, errNoProtocolRecord
}
return parseHTTP2Precentage(records[0])
}
// The record looks like http2=percentage
func parseHTTP2Precentage(record string) (int32, error) {
const key = "http2"
slices := strings.Split(record, "=")
if len(slices) != 2 {
return 0, fmt.Errorf("Malformed TXT record %s, expect http2=percentage", record)
}
if slices[0] != key {
return 0, fmt.Errorf("Incorrect key %s, expect %s", slices[0], key)
}
percentage, err := strconv.ParseInt(slices[1], 10, 32)
if err != nil {
return 0, err
}
return int32(percentage), nil
}