Golang Msg.SetQuestion方法代码示例

func TestDNS_ServiceLookup_TagPeriod(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register node
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "foo",
		Address:    "127.0.0.1",
		Service: &structs.NodeService{
			Service: "db",
			Tags:    []string{"v1.master"},
			Port:    12345,
		},
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("v1.master.db.service.consul.", dns.TypeSRV)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) != 1 {
		t.Fatalf("Bad: %#v", in)
	}

	srvRec, ok := in.Answer[0].(*dns.SRV)
	if !ok {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if srvRec.Port != 12345 {
		t.Fatalf("Bad: %#v", srvRec)
	}
	if srvRec.Target != "foo.node.dc1.consul." {
		t.Fatalf("Bad: %#v", srvRec)
	}

	aRec, ok := in.Extra[0].(*dns.A)
	if !ok {
		t.Fatalf("Bad: %#v", in.Extra[0])
	}
	if aRec.Hdr.Name != "foo.node.dc1.consul." {
		t.Fatalf("Bad: %#v", in.Extra[0])
	}
	if aRec.A.String() != "127.0.0.1" {
		t.Fatalf("Bad: %#v", in.Extra[0])
	}
}

func TestDNS_IsAlive(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	m := new(dns.Msg)
	m.SetQuestion("_test.consul.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) != 1 {
		t.Fatalf("Bad: %#v", in)
	}

	txt, ok := in.Answer[0].(*dns.TXT)
	if !ok {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if txt.Txt[0] != "ok" {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
}

func ExamplePrivateHandle() {
	dns.PrivateHandle("APAIR", TypeAPAIR, NewAPAIR)
	defer dns.PrivateHandleRemove(TypeAPAIR)

	rr, err := dns.NewRR("miek.nl. APAIR (1.2.3.4    1.2.3.5)")
	if err != nil {
		log.Fatal("could not parse APAIR record: ", err)
	}
	fmt.Println(rr)
	// Output: miek.nl.	3600	IN	APAIR	1.2.3.4 1.2.3.5

	m := new(dns.Msg)
	m.Id = 12345
	m.SetQuestion("miek.nl.", TypeAPAIR)
	m.Answer = append(m.Answer, rr)

	fmt.Println(m)
	// ;; opcode: QUERY, status: NOERROR, id: 12345
	// ;; flags: rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
	//
	// ;; QUESTION SECTION:
	// ;miek.nl.	IN	 APAIR
	//
	// ;; ANSWER SECTION:
	// miek.nl.	3600	IN	APAIR	1.2.3.4 1.2.3.5
}

// resolveCNAME is used to recursively resolve CNAME records
func (d *DNSServer) resolveCNAME(name string) []dns.RR {
	// Do nothing if we don't have a recursor
	if len(d.recursors) == 0 {
		return nil
	}

	// Ask for any A records
	m := new(dns.Msg)
	m.SetQuestion(name, dns.TypeA)

	// Make a DNS lookup request
	c := &dns.Client{Net: "udp"}
	var r *dns.Msg
	var rtt time.Duration
	var err error
	for _, recursor := range d.recursors {
		r, rtt, err = c.Exchange(m, recursor)
		if err == nil {
			d.logger.Printf("[DEBUG] dns: cname recurse RTT for %v (%v)", name, rtt)
			return r.Answer
		}
		d.logger.Printf("[ERR] dns: cname recurse failed for %v: %v", name, err)
	}
	d.logger.Printf("[ERR] dns: all resolvers failed for %v", name)
	return nil
}

func TestDNS_CaseInsensitiveNodeLookup(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register node
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "Foo",
		Address:    "127.0.0.1",
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("fOO.node.dc1.consul.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) != 1 {
		t.Fatalf("empty lookup: %#v", in)
	}
}

// Performs the actual query by service name (browse) or service instance name (lookup),
// start response listeners goroutines and loops over the entries channel.
func (c *client) query(params *LookupParams) error {
	var serviceName, serviceInstanceName string
	serviceName = fmt.Sprintf("%s.%s.", trimDot(params.Service), trimDot(params.Domain))
	if params.Instance != "" {
		serviceInstanceName = fmt.Sprintf("%s.%s", params.Instance, serviceName)
	}

	// send the query
	m := new(dns.Msg)
	if serviceInstanceName != "" {
		m.Question = []dns.Question{
			dns.Question{serviceInstanceName, dns.TypeSRV, dns.ClassINET},
			dns.Question{serviceInstanceName, dns.TypeTXT, dns.ClassINET},
		}
		m.RecursionDesired = false
	} else {
		m.SetQuestion(serviceName, dns.TypePTR)
		m.RecursionDesired = false
	}
	if err := c.sendQuery(m); err != nil {
		return err
	}

	return nil
}

func TestDNS_ServiceLookup_CNAME(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register node
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "google",
		Address:    "www.google.com",
		Service: &structs.NodeService{
			Service: "search",
			Port:    80,
		},
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("search.service.consul.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) != 4 {
		t.Fatalf("Bad: %#v", in)
	}

	// Should have google CNAME
	cnRec, ok := in.Answer[0].(*dns.CNAME)
	if !ok {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if cnRec.Target != "www.google.com." {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}

	// Check we recursively resolve
	for i := 1; i < 4; i++ {
		if _, ok := in.Answer[i].(*dns.A); !ok {
			t.Fatalf("Bad: %#v", in.Answer[i])
		}
	}
}

// Perform probing & announcement
//TODO: implement a proper probing & conflict resolution
func (s *server) probe() {
	q := new(dns.Msg)
	q.SetQuestion(s.service.ServiceInstanceName(), dns.TypePTR)
	q.RecursionDesired = false

	srv := &dns.SRV{
		Hdr: dns.RR_Header{
			Name:   s.service.ServiceInstanceName(),
			Rrtype: dns.TypeSRV,
			Class:  dns.ClassINET,
			Ttl:    3200,
		},
		Priority: 0,
		Weight:   0,
		Port:     uint16(s.service.Port),
		Target:   s.service.HostName,
	}
	txt := &dns.TXT{
		Hdr: dns.RR_Header{
			Name:   s.service.ServiceInstanceName(),
			Rrtype: dns.TypeTXT,
			Class:  dns.ClassINET,
			Ttl:    3200,
		},
		Txt: s.service.Text,
	}
	q.Ns = []dns.RR{srv, txt}

	randomizer := rand.New(rand.NewSource(time.Now().UnixNano()))
	for i := 0; i < 3; i++ {
		if err := s.multicastResponse(q); err != nil {
			log.Println("[ERR] bonjour: failed to send probe:", err.Error())
		}
		time.Sleep(time.Duration(randomizer.Intn(250)) * time.Millisecond)
	}

	resp := new(dns.Msg)
	resp.Answer = []dns.RR{}
	resp.Extra = []dns.RR{}
	s.composeLookupAnswers(resp, 3200)
	for i := 0; i < 3; i++ {
		if err := s.multicastResponse(resp); err != nil {
			log.Println("[ERR] bonjour: failed to send announcement:", err.Error())
		}
		time.Sleep(2 * time.Second)
	}
}

func TestDNS_NodeLookup_CNAME(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register node
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "google",
		Address:    "www.google.com",
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("google.node.consul.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	// Should have the CNAME record + a few A records
	if len(in.Answer) < 2 {
		t.Fatalf("Bad: %#v", in)
	}

	cnRec, ok := in.Answer[0].(*dns.CNAME)
	if !ok {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if cnRec.Target != "www.google.com." {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if cnRec.Hdr.Ttl != 0 {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
}

func TestDNS_NodeLookup_AAAA(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register node
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "bar",
		Address:    "::4242:4242",
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("bar.node.consul.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) != 1 {
		t.Fatalf("Bad: %#v", in)
	}

	aRec, ok := in.Answer[0].(*dns.AAAA)
	if !ok {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if aRec.AAAA.String() != "::4242:4242" {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if aRec.Hdr.Ttl != 0 {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
}

// Retrieve the MX records for miek.nl.
func ExampleMX() {
	config, _ := dns.ClientConfigFromFile("/etc/resolv.conf")
	c := new(dns.Client)
	m := new(dns.Msg)
	m.SetQuestion("miek.nl.", dns.TypeMX)
	m.RecursionDesired = true
	r, _, err := c.Exchange(m, config.Servers[0]+":"+config.Port)
	if err != nil {
		return
	}
	if r.Rcode != dns.RcodeSuccess {
		return
	}
	for _, a := range r.Answer {
		if mx, ok := a.(*dns.MX); ok {
			fmt.Printf("%s\n", mx.String())
		}
	}
}

func TestDNS_ReverseLookup_CustomDomain(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()
	srv.domain = dns.Fqdn("custom")

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register node
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "foo2",
		Address:    "127.0.0.2",
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("2.0.0.127.in-addr.arpa.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) != 1 {
		t.Fatalf("Bad: %#v", in)
	}

	ptrRec, ok := in.Answer[0].(*dns.PTR)
	if !ok {
		t.Fatalf("Bad: %#v", in.Answer[0])
	}
	if ptrRec.Ptr != "foo2.node.dc1.custom." {
		t.Fatalf("Bad: %#v", ptrRec)
	}
}

func TestDNS_Recurse(t *testing.T) {
	dir, srv := makeDNSServer(t)
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	m := new(dns.Msg)
	m.SetQuestion("apple.com.", dns.TypeANY)

	c := new(dns.Client)
	c.Net = "tcp"
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if len(in.Answer) == 0 {
		t.Fatalf("Bad: %#v", in)
	}
	if in.Rcode != dns.RcodeSuccess {
		t.Fatalf("Bad: %#v", in)
	}
}

// Retrieve the DNSKEY records of a zone and convert them
// to DS records for SHA1, SHA256 and SHA384.
func ExampleDS(zone string) {
	config, _ := dns.ClientConfigFromFile("/etc/resolv.conf")
	c := new(dns.Client)
	m := new(dns.Msg)
	if zone == "" {
		zone = "miek.nl"
	}
	m.SetQuestion(dns.Fqdn(zone), dns.TypeDNSKEY)
	m.SetEdns0(4096, true)
	r, _, err := c.Exchange(m, config.Servers[0]+":"+config.Port)
	if err != nil {
		return
	}
	if r.Rcode != dns.RcodeSuccess {
		return
	}
	for _, k := range r.Answer {
		if key, ok := k.(*dns.DNSKEY); ok {
			for _, alg := range []uint8{dns.SHA1, dns.SHA256, dns.SHA384} {
				fmt.Printf("%s; %d\n", key.ToDS(alg).String(), key.Flags)
			}
		}
	}
}

func TestDNS_ServiceLookup_OnlyPassing(t *testing.T) {
	dir, srv := makeDNSServerConfig(t, &DNSConfig{OnlyPassing: true})
	defer os.RemoveAll(dir)
	defer srv.agent.Shutdown()

	testutil.WaitForLeader(t, srv.agent.RPC, "dc1")

	// Register nodes
	args := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "foo",
		Address:    "127.0.0.1",
		Service: &structs.NodeService{
			Service: "db",
			Tags:    []string{"master"},
			Port:    12345,
		},
		Check: &structs.HealthCheck{
			CheckID:   "db",
			Name:      "db",
			ServiceID: "db",
			Status:    structs.HealthPassing,
		},
	}

	var out struct{}
	if err := srv.agent.RPC("Catalog.Register", args, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	args2 := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "bar",
		Address:    "127.0.0.2",
		Service: &structs.NodeService{
			Service: "db",
			Tags:    []string{"master"},
			Port:    12345,
		},
		Check: &structs.HealthCheck{
			CheckID:   "db",
			Name:      "db",
			ServiceID: "db",
			Status:    structs.HealthWarning,
		},
	}

	if err := srv.agent.RPC("Catalog.Register", args2, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	args3 := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "baz",
		Address:    "127.0.0.3",
		Service: &structs.NodeService{
			Service: "db",
			Tags:    []string{"master"},
			Port:    12345,
		},
		Check: &structs.HealthCheck{
			CheckID:   "db",
			Name:      "db",
			ServiceID: "db",
			Status:    structs.HealthCritical,
		},
	}

	if err := srv.agent.RPC("Catalog.Register", args3, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	args4 := &structs.RegisterRequest{
		Datacenter: "dc1",
		Node:       "quux",
		Address:    "127.0.0.4",
		Service: &structs.NodeService{
			Service: "db",
			Tags:    []string{"master"},
			Port:    12345,
		},
		Check: &structs.HealthCheck{
			CheckID:   "db",
			Name:      "db",
			ServiceID: "db",
			Status:    structs.HealthUnknown,
		},
	}

	if err := srv.agent.RPC("Catalog.Register", args4, &out); err != nil {
		t.Fatalf("err: %v", err)
	}

	m := new(dns.Msg)
	m.SetQuestion("db.service.consul.", dns.TypeANY)

	c := new(dns.Client)
	addr, _ := srv.agent.config.ClientListener("", srv.agent.config.Ports.DNS)
	in, _, err := c.Exchange(m, addr.String())
	if err != nil {
//.........这里部分代码省略.........