Add tcp/udp check connection input plugin

closes #650

CHANGELOG.md

@@ -20,6 +20,7 @@ they would like to output. Currently supports: "influx" and "graphite"
 - [#679](https://github.com/influxdata/telegraf/pull/679): File/stdout output plugin.
 - [#679](https://github.com/influxdata/telegraf/pull/679): Support for arbitrary output data formats.
 - [#695](https://github.com/influxdata/telegraf/pull/695): raindrops input plugin. Thanks @burdandrei!
+- [#650](https://github.com/influxdata/telegraf/pull/650): net_response input plugin. Thanks @titilambert!
 
 ### Bugfixes
 - [#443](https://github.com/influxdata/telegraf/issues/443): Fix Ping command timeout parameter on Linux.

README.md

@@ -171,6 +171,7 @@ Currently implemented sources:
 * memcached
 * mongodb
 * mysql
+* net_response
 * nginx
 * nsq
 * phpfpm

plugins/inputs/all/all.go

@@ -24,6 +24,7 @@ import (
 	_ "github.com/influxdata/telegraf/plugins/inputs/mqtt_consumer"
 	_ "github.com/influxdata/telegraf/plugins/inputs/mysql"
 	_ "github.com/influxdata/telegraf/plugins/inputs/nats_consumer"
+	_ "github.com/influxdata/telegraf/plugins/inputs/net_response"
 	_ "github.com/influxdata/telegraf/plugins/inputs/nginx"
 	_ "github.com/influxdata/telegraf/plugins/inputs/nsq"
 	_ "github.com/influxdata/telegraf/plugins/inputs/passenger"

plugins/inputs/net_response/README.md

@@ -0,0 +1,66 @@
+# Example Input Plugin
+
+The input plugin test UDP/TCP connections response time.
+It can also check response text.
+
+### Configuration:
+
+```
+# List of UDP/TCP connections you want to check
+[[inputs.net_response]]
+  protocol = "tcp"
+  # Server address (default IP localhost)
+  address = "github.com:80"
+  # Set timeout (default 1.0)
+  timeout = 1.0
+  # Set read timeout (default 1.0)
+  read_timeout = 1.0
+  # String sent to the server
+  send = "ssh"
+  # Expected string in answer
+  expect = "ssh"
+
+[[inputs.net_response]]
+  protocol = "tcp"
+  address = ":80"
+
+[[inputs.net_response]]
+  protocol = "udp"
+  # Server address (default IP localhost)
+  address = "github.com:80"
+  # Set timeout (default 1.0)
+  timeout = 1.0
+  # Set read timeout (default 1.0)
+  read_timeout = 1.0
+  # String sent to the server
+  send = "ssh"
+  # Expected string in answer
+  expect = "ssh"
+
+[[inputs.net_response]]
+  protocol = "udp"
+  address = "localhost:161"
+  timeout = 2.0
+```
+
+### Measurements & Fields:
+
+- net_response
+    - response_time (float, seconds)
+    - string_found (bool) # Only if "expected: option is set
+
+### Tags:
+
+- All measurements have the following tags:
+    - host
+    - port
+    - protocol
+
+### Example Output:
+
+```
+$ ./telegraf -config telegraf.conf -input-filter net_response -test
+net_response,host=127.0.0.1,port=22,protocol=tcp response_time=0.18070360500000002,string_found=true 1454785464182527094
+net_response,host=127.0.0.1,port=2222,protocol=tcp response_time=1.090124776,string_found=false 1454784433658942325
+
+```

plugins/inputs/net_response/net_response.go

@@ -0,0 +1,196 @@
+package net_response
+
+import (
+	"bufio"
+	"errors"
+	"net"
+	"net/textproto"
+	"regexp"
+	"time"
+
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/plugins/inputs"
+)
+
+// NetResponses struct
+type NetResponse struct {
+	Address     string
+	Timeout     float64
+	ReadTimeout float64
+	Send        string
+	Expect      string
+	Protocol    string
+}
+
+func (_ *NetResponse) Description() string {
+	return "TCP or UDP 'ping' given url and collect response time in seconds"
+}
+
+var sampleConfig = `
+  ### Protocol, must be "tcp" or "udp"
+  protocol = "tcp"
+  ### Server address (default localhost)
+  address = "github.com:80"
+  ### Set timeout (default 1.0 seconds)
+  timeout = 1.0
+  ### Set read timeout (default 1.0 seconds)
+  read_timeout = 1.0
+  ### Optional string sent to the server
+  # send = "ssh"
+  ### Optional expected string in answer
+  # expect = "ssh"
+`
+
+func (_ *NetResponse) SampleConfig() string {
+	return sampleConfig
+}
+
+func (t *NetResponse) TcpGather() (map[string]interface{}, error) {
+	// Prepare fields
+	fields := make(map[string]interface{})
+	// Start Timer
+	start := time.Now()
+	// Resolving
+	tcpAddr, err := net.ResolveTCPAddr("tcp", t.Address)
+	// Connecting
+	conn, err := net.DialTCP("tcp", nil, tcpAddr)
+	// Stop timer
+	responseTime := time.Since(start).Seconds()
+	// Handle error
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+	// Send string if needed
+	if t.Send != "" {
+		msg := []byte(t.Send)
+		conn.Write(msg)
+		conn.CloseWrite()
+		// Stop timer
+		responseTime = time.Since(start).Seconds()
+	}
+	// Read string if needed
+	if t.Expect != "" {
+		// Set read timeout
+		conn.SetReadDeadline(time.Now().Add(time.Duration(t.ReadTimeout) * time.Second))
+		// Prepare reader
+		reader := bufio.NewReader(conn)
+		tp := textproto.NewReader(reader)
+		// Read
+		data, err := tp.ReadLine()
+		// Stop timer
+		responseTime = time.Since(start).Seconds()
+		// Handle error
+		if err != nil {
+			fields["string_found"] = false
+		} else {
+			// Looking for string in answer
+			RegEx := regexp.MustCompile(`.*` + t.Expect + `.*`)
+			find := RegEx.FindString(string(data))
+			if find != "" {
+				fields["string_found"] = true
+			} else {
+				fields["string_found"] = false
+			}
+		}
+
+	}
+	fields["response_time"] = responseTime
+	return fields, nil
+}
+
+func (u *NetResponse) UdpGather() (map[string]interface{}, error) {
+	// Prepare fields
+	fields := make(map[string]interface{})
+	// Start Timer
+	start := time.Now()
+	// Resolving
+	udpAddr, err := net.ResolveUDPAddr("udp", u.Address)
+	LocalAddr, err := net.ResolveUDPAddr("udp", "127.0.0.1:0")
+	// Connecting
+	conn, err := net.DialUDP("udp", LocalAddr, udpAddr)
+	defer conn.Close()
+	// Handle error
+	if err != nil {
+		return nil, err
+	}
+	// Send string
+	msg := []byte(u.Send)
+	conn.Write(msg)
+	// Read string
+	// Set read timeout
+	conn.SetReadDeadline(time.Now().Add(time.Duration(u.ReadTimeout) * time.Second))
+	// Read
+	buf := make([]byte, 1024)
+	_, _, err = conn.ReadFromUDP(buf)
+	// Stop timer
+	responseTime := time.Since(start).Seconds()
+	// Handle error
+	if err != nil {
+		return nil, err
+	} else {
+		// Looking for string in answer
+		RegEx := regexp.MustCompile(`.*` + u.Expect + `.*`)
+		find := RegEx.FindString(string(buf))
+		if find != "" {
+			fields["string_found"] = true
+		} else {
+			fields["string_found"] = false
+		}
+	}
+	fields["response_time"] = responseTime
+	return fields, nil
+}
+
+func (c *NetResponse) Gather(acc telegraf.Accumulator) error {
+	// Set default values
+	if c.Timeout == 0 {
+		c.Timeout = 1.0
+	}
+	if c.ReadTimeout == 0 {
+		c.ReadTimeout = 1.0
+	}
+	// Check send and expected string
+	if c.Protocol == "udp" && c.Send == "" {
+		return errors.New("Send string cannot be empty")
+	}
+	if c.Protocol == "udp" && c.Expect == "" {
+		return errors.New("Expected string cannot be empty")
+	}
+	// Prepare host and port
+	host, port, err := net.SplitHostPort(c.Address)
+	if err != nil {
+		return err
+	}
+	if host == "" {
+		c.Address = "localhost:" + port
+	}
+	if port == "" {
+		return errors.New("Bad port")
+	}
+	// Prepare data
+	tags := map[string]string{"host": host, "port": port}
+	var fields map[string]interface{}
+	// Gather data
+	if c.Protocol == "tcp" {
+		fields, err = c.TcpGather()
+		tags["protocol"] = "tcp"
+	} else if c.Protocol == "udp" {
+		fields, err = c.UdpGather()
+		tags["protocol"] = "udp"
+	} else {
+		return errors.New("Bad protocol")
+	}
+	if err != nil {
+		return err
+	}
+	// Add metrics
+	acc.AddFields("net_response", fields, tags)
+	return nil
+}
+
+func init() {
+	inputs.Add("net_response", func() telegraf.Input {
+		return &NetResponse{}
+	})
+}

plugins/inputs/net_response/net_response_test.go

@@ -0,0 +1,198 @@
+package net_response
+
+import (
+	"net"
+	"regexp"
+	"sync"
+	"testing"
+
+	"github.com/influxdata/telegraf/testutil"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBadProtocol(t *testing.T) {
+	var acc testutil.Accumulator
+	// Init plugin
+	c := NetResponse{
+		Protocol: "unknownprotocol",
+		Address:  ":9999",
+	}
+	// Error
+	err1 := c.Gather(&acc)
+	require.Error(t, err1)
+	assert.Equal(t, "Bad protocol", err1.Error())
+}
+
+func TestTCPError(t *testing.T) {
+	var acc testutil.Accumulator
+	// Init plugin
+	c := NetResponse{
+		Protocol: "tcp",
+		Address:  ":9999",
+	}
+	// Error
+	err1 := c.Gather(&acc)
+	require.Error(t, err1)
+	assert.Equal(t, "dial tcp 127.0.0.1:9999: getsockopt: connection refused", err1.Error())
+}
+
+func TestTCPOK1(t *testing.T) {
+	var wg sync.WaitGroup
+	var acc testutil.Accumulator
+	// Init plugin
+	c := NetResponse{
+		Address:     "127.0.0.1:2004",
+		Send:        "test",
+		Expect:      "test",
+		ReadTimeout: 3.0,
+		Timeout:     1.0,
+		Protocol:    "tcp",
+	}
+	// Start TCP server
+	wg.Add(1)
+	go TCPServer(t, &wg)
+	wg.Wait()
+	// Connect
+	wg.Add(1)
+	err1 := c.Gather(&acc)
+	wg.Wait()
+	// Override response time
+	for _, p := range acc.Metrics {
+		p.Fields["response_time"] = 1.0
+	}
+	require.NoError(t, err1)
+	acc.AssertContainsTaggedFields(t,
+		"net_response",
+		map[string]interface{}{
+			"string_found":  true,
+			"response_time": 1.0,
+		},
+		map[string]string{"host": "127.0.0.1",
+			"port":     "2004",
+			"protocol": "tcp",
+		},
+	)
+	// Waiting TCPserver
+	wg.Wait()
+}
+
+func TestTCPOK2(t *testing.T) {
+	var wg sync.WaitGroup
+	var acc testutil.Accumulator
+	// Init plugin
+	c := NetResponse{
+		Address:     "127.0.0.1:2004",
+		Send:        "test",
+		Expect:      "test2",
+		ReadTimeout: 3.0,
+		Timeout:     1.0,
+		Protocol:    "tcp",
+	}
+	// Start TCP server
+	wg.Add(1)
+	go TCPServer(t, &wg)
+	wg.Wait()
+	// Connect
+	wg.Add(1)
+	err1 := c.Gather(&acc)
+	wg.Wait()
+	// Override response time
+	for _, p := range acc.Metrics {
+		p.Fields["response_time"] = 1.0
+	}
+	require.NoError(t, err1)
+	acc.AssertContainsTaggedFields(t,
+		"net_response",
+		map[string]interface{}{
+			"string_found":  false,
+			"response_time": 1.0,
+		},
+		map[string]string{"host": "127.0.0.1",
+			"port":     "2004",
+			"protocol": "tcp",
+		},
+	)
+	// Waiting TCPserver
+	wg.Wait()
+}
+
+func TestUDPrror(t *testing.T) {
+	var acc testutil.Accumulator
+	// Init plugin
+	c := NetResponse{
+		Address:  ":9999",
+		Send:     "test",
+		Expect:   "test",
+		Protocol: "udp",
+	}
+	// Error
+	err1 := c.Gather(&acc)
+	require.Error(t, err1)
+	assert.Regexp(t, regexp.MustCompile(`read udp 127.0.0.1:[0-9]*->127.0.0.1:9999: recvfrom: connection refused`), err1.Error())
+}
+
+func TestUDPOK1(t *testing.T) {
+	var wg sync.WaitGroup
+	var acc testutil.Accumulator
+	// Init plugin
+	c := NetResponse{
+		Address:     "127.0.0.1:2004",
+		Send:        "test",
+		Expect:      "test",
+		ReadTimeout: 3.0,
+		Timeout:     1.0,
+		Protocol:    "udp",
+	}
+	// Start UDP server
+	wg.Add(1)
+	go UDPServer(t, &wg)
+	wg.Wait()
+	// Connect
+	wg.Add(1)
+	err1 := c.Gather(&acc)
+	wg.Wait()
+	// Override response time
+	for _, p := range acc.Metrics {
+		p.Fields["response_time"] = 1.0
+	}
+	require.NoError(t, err1)
+	acc.AssertContainsTaggedFields(t,
+		"net_response",
+		map[string]interface{}{
+			"string_found":  true,
+			"response_time": 1.0,
+		},
+		map[string]string{"host": "127.0.0.1",
+			"port":     "2004",
+			"protocol": "udp",
+		},
+	)
+	// Waiting TCPserver
+	wg.Wait()
+}
+
+func UDPServer(t *testing.T, wg *sync.WaitGroup) {
+	udpAddr, _ := net.ResolveUDPAddr("udp", "127.0.0.1:2004")
+	conn, _ := net.ListenUDP("udp", udpAddr)
+	wg.Done()
+	buf := make([]byte, 1024)
+	_, remoteaddr, _ := conn.ReadFromUDP(buf)
+	conn.WriteToUDP(buf, remoteaddr)
+	conn.Close()
+	wg.Done()
+}
+
+func TCPServer(t *testing.T, wg *sync.WaitGroup) {
+	tcpAddr, _ := net.ResolveTCPAddr("tcp", "127.0.0.1:2004")
+	tcpServer, _ := net.ListenTCP("tcp", tcpAddr)
+	wg.Done()
+	conn, _ := tcpServer.AcceptTCP()
+	buf := make([]byte, 1024)
+	conn.Read(buf)
+	conn.Write(buf)
+	conn.CloseWrite()
+	tcpServer.Close()
+	wg.Done()
+}