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package test
import (
"testing"
"github.com/miekg/dns"
)
func TestProxyThreeWay(t *testing.T) {
// Run 3 CoreDNS server, 2 upstream ones and a proxy. 1 Upstream is unhealthy after 1 query, but after
// that we should still be able to send to the other one.
// Backend CoreDNS's.
corefileUp1 := `example.org:0 {
erratic {
drop 2
}
}
`
up1, err := CoreDNSServer(corefileUp1)
if err != nil {
t.Fatalf("Could not get CoreDNS serving instance: %s", err)
}
defer up1.Stop()
corefileUp2 := `example.org:0 {
whoami
}
`
up2, err := CoreDNSServer(corefileUp2)
if err != nil {
t.Fatalf("Could not get CoreDNS serving instance: %s", err)
}
defer up2.Stop()
addr1, _ := CoreDNSServerPorts(up1, 0)
if addr1 == "" {
t.Fatalf("Could not get UDP listening port")
}
addr2, _ := CoreDNSServerPorts(up2, 0)
if addr2 == "" {
t.Fatalf("Could not get UDP listening port")
}
// Proxying CoreDNS.
corefileProxy := `example.org:0 {
proxy . ` + addr1 + " " + addr2 + ` {
max_fails 1
}
}`
prx, err := CoreDNSServer(corefileProxy)
if err != nil {
t.Fatalf("Could not get CoreDNS serving instance: %s", err)
}
defer prx.Stop()
addr, _ := CoreDNSServerPorts(prx, 0)
if addr == "" {
t.Fatalf("Could not get UDP listening port")
}
m := new(dns.Msg)
m.SetQuestion("example.org.", dns.TypeA)
for i := 0; i < 10; i++ {
r, err := dns.Exchange(m, addr)
if err != nil {
continue
}
// We would previously get SERVFAIL, so just getting answers here
// is a good sign. The actual timeouts are handled in the err != nil case
// above.
if r.Rcode != dns.RcodeSuccess {
t.Fatalf("Expected success rcode, got %d", r.Rcode)
}
}
}
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