feat(inputs.dns_query): Add IP field(s) (#12519)

plugins/inputs/dns_query/README.md

@@ -33,8 +33,14 @@ See the [CONFIGURATION.md][CONFIGURATION.md] for more details.
   ## Dns server port.
   # port = 53
 
-  ## Query timeout in seconds.
+  ## Query timeout
-  # timeout = 2
+  # timeout = "2s"
+
+  ## Include the specified additional properties in the resulting metric.
+  ## The following values are supported:
+  ##    "first_ip" -- return IP of the first A and AAAA answer
+  ##    "all_ips"  -- return IPs of all A and AAAA answers
+  # include_fields = []
 ```
 
 ## Metrics

plugins/inputs/dns_query/dns_query.go

@@ -12,6 +12,7 @@ import (
 	"github.com/miekg/dns"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/config"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
@@ -27,76 +28,39 @@ const (
 )
 
 type DNSQuery struct {
-	// Domains or subdomains to query
+	Domains       []string        `toml:"domains"`
-	Domains []string
+	Network       string          `toml:"network"`
-
+	Servers       []string        `toml:"servers"`
-	// Network protocol name
-	Network string
-
-	// Server to query
-	Servers []string
-
-	// Record type
 	RecordType    string          `toml:"record_type"`
+	Port          int             `toml:"port"`
+	Timeout       config.Duration `toml:"timeout"`
+	IncludeFields []string        `toml:"include_fields"`
 
-	// DNS server port number
+	fieldEnabled map[string]bool
-	Port int
-
-	// Dns query timeout in seconds. 0 means no timeout
-	Timeout int
 }
 
 func (*DNSQuery) SampleConfig() string {
 	return sampleConfig
 }
 
-func (d *DNSQuery) Gather(acc telegraf.Accumulator) error {
+func (d *DNSQuery) Init() error {
-	var wg sync.WaitGroup
+	// Convert the included fields into a lookup-table
-	d.setDefaultValues()
+	d.fieldEnabled = make(map[string]bool, len(d.IncludeFields))
-
+	for _, f := range d.IncludeFields {
-	for _, domain := range d.Domains {
+		switch f {
-		for _, server := range d.Servers {
+		case "first_ip", "all_ips":
-			wg.Add(1)
+		default:
-			go func(domain, server string) {
+			return fmt.Errorf("invalid field %q included", f)
-				fields := make(map[string]interface{}, 2)
+		}
-				tags := map[string]string{
+		d.fieldEnabled[f] = true
-					"server":      server,
-					"domain":      domain,
-					"record_type": d.RecordType,
 	}
 
-				dnsQueryTime, rcode, err := d.getDNSQueryTime(domain, server)
+	// Set defaults
-				if rcode >= 0 {
-					tags["rcode"] = dns.RcodeToString[rcode]
-					fields["rcode_value"] = rcode
-				}
-				if err == nil {
-					setResult(Success, fields, tags)
-					fields["query_time_ms"] = dnsQueryTime
-				} else if opErr, ok := err.(*net.OpError); ok && opErr.Timeout() {
-					setResult(Timeout, fields, tags)
-				} else if err != nil {
-					setResult(Error, fields, tags)
-					acc.AddError(err)
-				}
-
-				acc.AddFields("dns_query", fields, tags)
-
-				wg.Done()
-			}(domain, server)
-		}
-	}
-
-	wg.Wait()
-	return nil
-}
-
-func (d *DNSQuery) setDefaultValues() {
 	if d.Network == "" {
 		d.Network = "udp"
 	}
 
-	if len(d.RecordType) == 0 {
+	if d.RecordType == "" {
 		d.RecordType = "NS"
 	}
 
@@ -105,39 +69,106 @@ func (d *DNSQuery) setDefaultValues() {
 		d.RecordType = "NS"
 	}
 
-	if d.Port == 0 {
+	if d.Port < 1 {
 		d.Port = 53
 	}
 
-	if d.Timeout == 0 {
+	return nil
-		d.Timeout = 2
-	}
 }
 
-func (d *DNSQuery) getDNSQueryTime(domain string, server string) (float64, int, error) {
+func (d *DNSQuery) Gather(acc telegraf.Accumulator) error {
-	dnsQueryTime := float64(0)
+	var wg sync.WaitGroup
 
-	c := new(dns.Client)
+	for _, domain := range d.Domains {
-	c.ReadTimeout = time.Duration(d.Timeout) * time.Second
+		for _, server := range d.Servers {
-	c.Net = d.Network
+			wg.Add(1)
+			go func(domain, server string) {
+				defer wg.Done()
+
+				fields, tags, err := d.query(domain, server)
+				if err != nil {
+					if opErr, ok := err.(*net.OpError); !ok || !opErr.Timeout() {
+						acc.AddError(err)
+					}
+				}
+				acc.AddFields("dns_query", fields, tags)
+			}(domain, server)
+		}
+	}
+	wg.Wait()
+
+	return nil
+}
+
+func (d *DNSQuery) query(domain string, server string) (map[string]interface{}, map[string]string, error) {
+	tags := map[string]string{
+		"server":      server,
+		"domain":      domain,
+		"record_type": d.RecordType,
+		"result":      "error",
+	}
+
+	fields := map[string]interface{}{
+		"query_time_ms": float64(0),
+		"result_code":   uint64(Error),
+	}
+
+	c := dns.Client{
+		ReadTimeout: time.Duration(d.Timeout),
+		Net:         d.Network,
+	}
 
-	m := new(dns.Msg)
 	recordType, err := d.parseRecordType()
 	if err != nil {
-		return dnsQueryTime, -1, err
+		return fields, tags, err
 	}
-	m.SetQuestion(dns.Fqdn(domain), recordType)
-	m.RecursionDesired = true
 
-	r, rtt, err := c.Exchange(m, net.JoinHostPort(server, strconv.Itoa(d.Port)))
+	var msg dns.Msg
+	msg.SetQuestion(dns.Fqdn(domain), recordType)
+	msg.RecursionDesired = true
+
+	addr := net.JoinHostPort(server, strconv.Itoa(d.Port))
+	r, rtt, err := c.Exchange(&msg, addr)
 	if err != nil {
-		return dnsQueryTime, -1, err
+		if opErr, ok := err.(*net.OpError); ok && opErr.Timeout() {
+			tags["result"] = "timeout"
+			fields["result_code"] = uint64(Timeout)
+			return fields, tags, err
 		}
+		return fields, tags, err
+	}
+
+	// Fill valid fields
+	tags["rcode"] = dns.RcodeToString[r.Rcode]
+	fields["rcode_value"] = r.Rcode
+	fields["query_time_ms"] = float64(rtt.Nanoseconds()) / 1e6
+
+	// Handle the failure case
 	if r.Rcode != dns.RcodeSuccess {
-		return dnsQueryTime, r.Rcode, fmt.Errorf("Invalid answer (%s) from %s after %s query for %s", dns.RcodeToString[r.Rcode], server, d.RecordType, domain)
+		return fields, tags, fmt.Errorf("invalid answer (%s) from %s after %s query for %s", dns.RcodeToString[r.Rcode], server, d.RecordType, domain)
 	}
-	dnsQueryTime = float64(rtt.Nanoseconds()) / 1e6
+
-	return dnsQueryTime, r.Rcode, nil
+	// Success
+	tags["result"] = "success"
+	fields["result_code"] = uint64(Success)
+
+	if d.fieldEnabled["first_ip"] {
+		for _, record := range r.Answer {
+			if ip, found := extractIP(record); found {
+				fields["ip"] = ip
+				break
+			}
+		}
+	}
+	if d.fieldEnabled["all_ips"] {
+		for i, record := range r.Answer {
+			if ip, found := extractIP(record); found {
+				fields["ip_"+strconv.Itoa(i)] = ip
+			}
+		}
+	}
+
+	return fields, tags, nil
 }
 
 func (d *DNSQuery) parseRecordType() (uint16, error) {
@@ -168,29 +199,26 @@ func (d *DNSQuery) parseRecordType() (uint16, error) {
 	case "TXT":
 		recordType = dns.TypeTXT
 	default:
-		err = fmt.Errorf("Record type %s not recognized", d.RecordType)
+		err = fmt.Errorf("record type %s not recognized", d.RecordType)
 	}
 
 	return recordType, err
 }
 
-func setResult(result ResultType, fields map[string]interface{}, tags map[string]string) {
+func extractIP(record dns.RR) (string, bool) {
-	var tag string
+	if r, ok := record.(*dns.A); ok {
-	switch result {
+		return r.A.String(), true
-	case Success:
-		tag = "success"
-	case Timeout:
-		tag = "timeout"
-	case Error:
-		tag = "error"
 	}
-
+	if r, ok := record.(*dns.AAAA); ok {
-	tags["result"] = tag
+		return r.AAAA.String(), true
-	fields["result_code"] = uint64(result)
+	}
+	return "", false
 }
 
 func init() {
 	inputs.Add("dns_query", func() telegraf.Input {
-		return &DNSQuery{}
+		return &DNSQuery{
+			Timeout: config.Duration(2 * time.Second),
+		}
 	})
 }

plugins/inputs/dns_query/dns_query_test.go

@@ -7,6 +7,9 @@ import (
 	"github.com/miekg/dns"
 	"github.com/stretchr/testify/require"
 
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/config"
+	"github.com/influxdata/telegraf/metric"
 	"github.com/influxdata/telegraf/testutil"
 )
 
@@ -17,116 +20,141 @@ func TestGathering(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skipping network-dependent test in short mode.")
 	}
-	var dnsConfig = DNSQuery{
+
+	dnsConfig := DNSQuery{
 		Servers: servers,
 		Domains: domains,
+		Timeout: config.Duration(2 * time.Second),
 	}
-	var acc testutil.Accumulator
 
-	err := acc.GatherError(dnsConfig.Gather)
+	var acc testutil.Accumulator
-	require.NoError(t, err)
+	require.NoError(t, dnsConfig.Init())
+	require.NoError(t, acc.GatherError(dnsConfig.Gather))
 	metric, ok := acc.Get("dns_query")
 	require.True(t, ok)
-	queryTime, _ := metric.Fields["query_time_ms"].(float64)
+	queryTime, ok := metric.Fields["query_time_ms"].(float64)
-
+	require.True(t, ok)
-	require.NotEqual(t, 0, queryTime)
+	require.NotEqual(t, float64(0), queryTime)
 }
 
 func TestGatheringMxRecord(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skipping network-dependent test in short mode.")
 	}
-	var dnsConfig = DNSQuery{
+
+	dnsConfig := DNSQuery{
 		Servers:    servers,
 		Domains:    domains,
+		RecordType: "MX",
+		Timeout:    config.Duration(2 * time.Second),
 	}
 	var acc testutil.Accumulator
-	dnsConfig.RecordType = "MX"
 
-	err := acc.GatherError(dnsConfig.Gather)
+	require.NoError(t, dnsConfig.Init())
-	require.NoError(t, err)
+	require.NoError(t, acc.GatherError(dnsConfig.Gather))
 	metric, ok := acc.Get("dns_query")
 	require.True(t, ok)
-	queryTime, _ := metric.Fields["query_time_ms"].(float64)
+	queryTime, ok := metric.Fields["query_time_ms"].(float64)
-
+	require.True(t, ok)
-	require.NotEqual(t, 0, queryTime)
+	require.NotEqual(t, float64(0), queryTime)
 }
 
 func TestGatheringRootDomain(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skipping network-dependent test in short mode.")
 	}
-	var dnsConfig = DNSQuery{
+
+	dnsConfig := DNSQuery{
 		Servers:    servers,
 		Domains:    []string{"."},
 		RecordType: "MX",
+		Timeout:    config.Duration(2 * time.Second),
 	}
+	require.NoError(t, dnsConfig.Init())
+
 	var acc testutil.Accumulator
-	tags := map[string]string{
+	require.NoError(t, acc.GatherError(dnsConfig.Gather))
+
+	m, ok := acc.Get("dns_query")
+	require.True(t, ok)
+	queryTime, ok := m.Fields["query_time_ms"].(float64)
+	require.True(t, ok)
+
+	expected := []telegraf.Metric{
+		metric.New(
+			"dns_query",
+			map[string]string{
 				"server":      "8.8.8.8",
 				"domain":      ".",
 				"record_type": "MX",
 				"rcode":       "NOERROR",
 				"result":      "success",
-	}
+			},
-	fields := map[string]interface{}{
+			map[string]interface{}{
 				"rcode_value":   0,
 				"result_code":   uint64(0),
+				"query_time_ms": queryTime,
+			},
+			time.Unix(0, 0),
+		),
 	}
-
+	testutil.RequireMetricsEqual(t, expected, acc.GetTelegrafMetrics(), testutil.IgnoreTime())
-	err := acc.GatherError(dnsConfig.Gather)
-	require.NoError(t, err)
-	metric, ok := acc.Get("dns_query")
-	require.True(t, ok)
-	queryTime, _ := metric.Fields["query_time_ms"].(float64)
-
-	fields["query_time_ms"] = queryTime
-	acc.AssertContainsTaggedFields(t, "dns_query", fields, tags)
 }
 
 func TestMetricContainsServerAndDomainAndRecordTypeTags(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skipping network-dependent test in short mode.")
 	}
-	var dnsConfig = DNSQuery{
+
+	dnsConfig := DNSQuery{
 		Servers: servers,
 		Domains: domains,
+		Timeout: config.Duration(2 * time.Second),
 	}
+	require.NoError(t, dnsConfig.Init())
+
 	var acc testutil.Accumulator
-	tags := map[string]string{
+	require.NoError(t, acc.GatherError(dnsConfig.Gather))
+
+	m, ok := acc.Get("dns_query")
+	require.True(t, ok)
+	queryTime, ok := m.Fields["query_time_ms"].(float64)
+	require.True(t, ok)
+	expected := []telegraf.Metric{
+		metric.New(
+			"dns_query",
+			map[string]string{
 				"server":      "8.8.8.8",
 				"domain":      "google.com",
 				"record_type": "NS",
 				"rcode":       "NOERROR",
 				"result":      "success",
-	}
+			},
-	fields := map[string]interface{}{
+			map[string]interface{}{
 				"rcode_value":   0,
 				"result_code":   uint64(0),
+				"query_time_ms": queryTime,
+			},
+			time.Unix(0, 0),
+		),
 	}
-
+	testutil.RequireMetricsEqual(t, expected, acc.GetTelegrafMetrics(), testutil.IgnoreTime())
-	err := acc.GatherError(dnsConfig.Gather)
-	require.NoError(t, err)
-	metric, ok := acc.Get("dns_query")
-	require.True(t, ok)
-	queryTime, _ := metric.Fields["query_time_ms"].(float64)
-
-	fields["query_time_ms"] = queryTime
-	acc.AssertContainsTaggedFields(t, "dns_query", fields, tags)
 }
 
 func TestGatheringTimeout(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skipping network-dependent test in short mode.")
 	}
-	var dnsConfig = DNSQuery{
+
+	dnsConfig := DNSQuery{
 		Servers: servers,
 		Domains: domains,
+		Timeout: config.Duration(1 * time.Second),
+		Port:    60054,
 	}
-	var acc testutil.Accumulator
+	require.NoError(t, dnsConfig.Init())
-	dnsConfig.Port = 60054
-	dnsConfig.Timeout = 1
 
+	var acc testutil.Accumulator
 	channel := make(chan error, 1)
 	go func() {
 		channel <- acc.GatherError(dnsConfig.Gather)
@@ -140,76 +168,95 @@ func TestGatheringTimeout(t *testing.T) {
 }
 
 func TestSettingDefaultValues(t *testing.T) {
-	dnsConfig := DNSQuery{}
+	dnsConfig := DNSQuery{
-
+		Timeout: config.Duration(2 * time.Second),
-	dnsConfig.setDefaultValues()
+	}
-
+	require.NoError(t, dnsConfig.Init())
 	require.Equal(t, []string{"."}, dnsConfig.Domains, "Default domain not equal \".\"")
 	require.Equal(t, "NS", dnsConfig.RecordType, "Default record type not equal 'NS'")
 	require.Equal(t, 53, dnsConfig.Port, "Default port number not equal 53")
-	require.Equal(t, 2, dnsConfig.Timeout, "Default timeout not equal 2")
+	require.Equal(t, config.Duration(2*time.Second), dnsConfig.Timeout, "Default timeout not equal 2s")
-
-	dnsConfig = DNSQuery{Domains: []string{"."}}
-
-	dnsConfig.setDefaultValues()
 
+	dnsConfig = DNSQuery{
+		Domains: []string{"."},
+		Timeout: config.Duration(2 * time.Second),
+	}
+	require.NoError(t, dnsConfig.Init())
 	require.Equal(t, "NS", dnsConfig.RecordType, "Default record type not equal 'NS'")
 }
 
 func TestRecordTypeParser(t *testing.T) {
-	var dnsConfig = DNSQuery{}
+	tests := []struct {
-	var recordType uint16
+		record   string
+		expected uint16
+	}{
+		{
+			record:   "A",
+			expected: dns.TypeA,
+		},
+		{
+			record:   "AAAA",
+			expected: dns.TypeAAAA,
+		},
+		{
+			record:   "ANY",
+			expected: dns.TypeANY,
+		},
+		{
+			record:   "CNAME",
+			expected: dns.TypeCNAME,
+		},
+		{
+			record:   "MX",
+			expected: dns.TypeMX,
+		},
+		{
+			record:   "NS",
+			expected: dns.TypeNS,
+		},
+		{
+			record:   "PTR",
+			expected: dns.TypePTR,
+		},
+		{
+			record:   "SOA",
+			expected: dns.TypeSOA,
+		},
+		{
+			record:   "SPF",
+			expected: dns.TypeSPF,
+		},
+		{
+			record:   "SRV",
+			expected: dns.TypeSRV,
+		},
+		{
+			record:   "TXT",
+			expected: dns.TypeTXT,
+		},
+	}
 
-	dnsConfig.RecordType = "A"
+	for _, tt := range tests {
-	recordType, _ = dnsConfig.parseRecordType()
+		t.Run(tt.record, func(t *testing.T) {
-	require.Equal(t, dns.TypeA, recordType)
+			plugin := DNSQuery{
-
+				Timeout:    config.Duration(2 * time.Second),
-	dnsConfig.RecordType = "AAAA"
+				Domains:    []string{"example.com"},
-	recordType, _ = dnsConfig.parseRecordType()
+				RecordType: tt.record,
-	require.Equal(t, dns.TypeAAAA, recordType)
+			}
-
+			require.NoError(t, plugin.Init())
-	dnsConfig.RecordType = "ANY"
+			recordType, err := plugin.parseRecordType()
-	recordType, _ = dnsConfig.parseRecordType()
+			require.NoError(t, err)
-	require.Equal(t, dns.TypeANY, recordType)
+			require.Equal(t, tt.expected, recordType)
-
+		})
-	dnsConfig.RecordType = "CNAME"
+	}
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeCNAME, recordType)
-
-	dnsConfig.RecordType = "MX"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeMX, recordType)
-
-	dnsConfig.RecordType = "NS"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeNS, recordType)
-
-	dnsConfig.RecordType = "PTR"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypePTR, recordType)
-
-	dnsConfig.RecordType = "SOA"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeSOA, recordType)
-
-	dnsConfig.RecordType = "SPF"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeSPF, recordType)
-
-	dnsConfig.RecordType = "SRV"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeSRV, recordType)
-
-	dnsConfig.RecordType = "TXT"
-	recordType, _ = dnsConfig.parseRecordType()
-	require.Equal(t, dns.TypeTXT, recordType)
 }
 
 func TestRecordTypeParserError(t *testing.T) {
-	var dnsConfig = DNSQuery{}
+	plugin := DNSQuery{
-	var err error
+		Timeout:    config.Duration(2 * time.Second),
+		RecordType: "nil",
+	}
 
-	dnsConfig.RecordType = "nil"
+	_, err := plugin.parseRecordType()
-	_, err = dnsConfig.parseRecordType()
 	require.Error(t, err)
 }

plugins/inputs/dns_query/sample.conf

@@ -16,5 +16,11 @@
   ## Dns server port.
   # port = 53
 
-  ## Query timeout in seconds.
+  ## Query timeout
-  # timeout = 2
+  # timeout = "2s"
+
+  ## Include the specified additional properties in the resulting metric.
+  ## The following values are supported:
+  ##    "first_ip" -- return IP of the first A and AAAA answer
+  ##    "all_ips"  -- return IPs of all A and AAAA answers
+  # include_fields = []