71 lines
1.1 KiB
Go
71 lines
1.1 KiB
Go
package hosts
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import (
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"net"
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"time"
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)
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const (
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notIPQuery = 0
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_IP4Query = 4
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_IP6Query = 6
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)
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var (
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zeroDuration = time.Duration(0)
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)
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type Hosts interface {
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Get(domain string, family int) ([]net.IP, time.Duration, bool)
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}
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type ProviderList struct {
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providers []Provider
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}
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type Provider interface {
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Get(domain string) ([]string, time.Duration, bool)
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}
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func NewHosts(providers []Provider) Hosts {
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return &ProviderList{providers}
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}
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/*
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Match local /etc/hosts file first, remote redis records second
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*/
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func (h *ProviderList) Get(domain string, family int) ([]net.IP, time.Duration, bool) {
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var sips []string
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var ok bool
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var ip net.IP
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var ips []net.IP
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var ttl time.Duration
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for _, provider := range h.providers {
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sips, ttl, ok = provider.Get(domain)
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if ok {
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break
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}
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}
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if sips == nil {
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return nil, zeroDuration, false
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}
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for _, sip := range sips {
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switch family {
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case _IP4Query:
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ip = net.ParseIP(sip).To4()
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case _IP6Query:
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ip = net.ParseIP(sip).To16()
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default:
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continue
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}
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if ip != nil {
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ips = append(ips, ip)
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}
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}
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return ips, ttl, ips != nil
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} |