cloudflare/cloudflared
Publicmirrored from https://github.com/cloudflare/cloudflaredAvailable
edgediscovery/protocol.go
45lines · modecode
| 1 | package edgediscovery |
| 2 | |
| 3 | import ( |
| 4 | "fmt" |
| 5 | "net" |
| 6 | "strconv" |
| 7 | "strings" |
| 8 | ) |
| 9 | |
| 10 | const ( |
| 11 | protocolRecord = "protocol.argotunnel.com" |
| 12 | ) |
| 13 | |
| 14 | var ( |
| 15 | errNoProtocolRecord = fmt.Errorf("No TXT record found for %s to determine connection protocol", protocolRecord) |
| 16 | ) |
| 17 | |
| 18 | func HTTP2Percentage() (int32, error) { |
| 19 | records, err := net.LookupTXT(protocolRecord) |
| 20 | if err != nil { |
| 21 | return 0, err |
| 22 | } |
| 23 | if len(records) == 0 { |
| 24 | return 0, errNoProtocolRecord |
| 25 | } |
| 26 | return parseHTTP2Precentage(records[0]) |
| 27 | } |
| 28 | |
| 29 | // The record looks like http2=percentage |
| 30 | func parseHTTP2Precentage(record string) (int32, error) { |
| 31 | const key = "http2" |
| 32 | slices := strings.Split(record, "=") |
| 33 | if len(slices) != 2 { |
| 34 | return 0, fmt.Errorf("Malformed TXT record %s, expect http2=percentage", record) |
| 35 | } |
| 36 | if slices[0] != key { |
| 37 | return 0, fmt.Errorf("Incorrect key %s, expect %s", slices[0], key) |
| 38 | } |
| 39 | percentage, err := strconv.ParseInt(slices[1], 10, 32) |
| 40 | if err != nil { |
| 41 | return 0, err |
| 42 | } |
| 43 | return int32(percentage), nil |
| 44 | |
| 45 | } |
| 46 | |