Files
selfpost/internal/dnscheck/resolver_test.go
T
mix af9f89b628 release: 0.3.0: PTR fix via public resolvers; monitoring URLs and nav icons
panel: the PTR (reverse DNS) check no longer reports a correctly published
Fixed:
  - panel: the PTR (reverse DNS) check no longer reports a correctly published
Changed:
  - panel: the three monitoring pages now live at URLs that match their nav
  - panel: each entry in the navigation bar now carries an icon beside its label,
  - panel: the navigation bar is laid out as two rows on purpose — the signed-in

Full detail: CHANGELOG.md (0.3.0).
2026-09-22 15:24:51 +03:00

101 lines
3.0 KiB
Go

package dnscheck
import (
"context"
"errors"
"net"
"testing"
)
func TestWithDefaultPort(t *testing.T) {
cases := map[string]string{
"1.1.1.1": "1.1.1.1:53",
"1.1.1.1:5353": "1.1.1.1:5353",
"dns.example.com": "dns.example.com:53",
"2606:4700:4700::": "[2606:4700:4700::]:53",
"[::1]:5353": "[::1]:5353",
}
for in, want := range cases {
if got := withDefaultPort(in); got != want {
t.Errorf("withDefaultPort(%q) = %q, want %q", in, got, want)
}
}
}
func TestParseResolvers(t *testing.T) {
got := ParseResolvers(" 1.1.1.1 , ,8.8.8.8:53,")
want := []string{"1.1.1.1", "8.8.8.8:53"}
if len(got) != len(want) {
t.Fatalf("got %q, want %q", got, want)
}
for i := range want {
if got[i] != want[i] {
t.Fatalf("got %q, want %q", got, want)
}
}
if r := ParseResolvers(""); len(r) != 0 {
t.Errorf("empty string parsed to %q, want nothing", r)
}
}
func TestNewExternalResolverFallsBackToDefaults(t *testing.T) {
if n := len(newExternalResolver(nil).servers); n != len(DefaultResolvers) {
t.Errorf("resolver count = %d, want %d (the defaults)", n, len(DefaultResolvers))
}
}
// The checks must reach the second resolver when the first is unreachable, but
// must not second-guess an authoritative "no such name" — otherwise a domain
// that genuinely lacks a record costs one timeout per configured resolver.
func TestQueryEachTriesTheNextResolverOnlyOnFailure(t *testing.T) {
servers := []*net.Resolver{{}, {}, {}}
asked := 0
got, err := queryEach(servers, func(*net.Resolver) (string, error) {
asked++
if asked < 3 {
return "", &net.DNSError{Err: "timed out", IsTimeout: true}
}
return "answer", nil
})
if err != nil || got != "answer" {
t.Fatalf("got (%q, %v), want (\"answer\", nil)", got, err)
}
if asked != 3 {
t.Errorf("asked %d resolvers, want 3", asked)
}
asked = 0
_, err = queryEach(servers, func(*net.Resolver) (string, error) {
asked++
return "", notFound("absent.example")
})
var dnsErr *net.DNSError
if !errors.As(err, &dnsErr) || !dnsErr.IsNotFound {
t.Fatalf("err = %v, want a not-found DNSError", err)
}
if asked != 1 {
t.Errorf("NXDOMAIN asked %d resolvers, want 1 — it is an answer, not a failure", asked)
}
}
// The reason this package does not use net.DefaultResolver: systemd-resolved
// answers PTR queries for the machine's own addresses out of the local
// hostname, which is not what the rest of the internet sees. The dial hook must
// therefore ignore the address the standard resolver picked from
// /etc/resolv.conf and connect to the configured one.
func TestExternalResolverDialsOnlyTheConfiguredAddress(t *testing.T) {
e := newExternalResolver([]string{"192.0.2.53"})
if len(e.servers) != 1 {
t.Fatalf("servers = %d, want 1", len(e.servers))
}
conn, err := e.servers[0].Dial(context.Background(), "udp", "127.0.0.53:53")
if err != nil {
t.Fatalf("dial: %v", err)
}
defer conn.Close()
if got := conn.RemoteAddr().String(); got != "192.0.2.53:53" {
t.Errorf("connected to %q, want 192.0.2.53:53 (the system resolver won)", got)
}
}