add http_response plugin

plugins/inputs/all/all.go

@@ -14,6 +14,7 @@ import (
 	_ "github.com/influxdata/telegraf/plugins/inputs/exec"
 	_ "github.com/influxdata/telegraf/plugins/inputs/github_webhooks"
 	_ "github.com/influxdata/telegraf/plugins/inputs/haproxy"
+	_ "github.com/influxdata/telegraf/plugins/inputs/http_response"
 	_ "github.com/influxdata/telegraf/plugins/inputs/httpjson"
 	_ "github.com/influxdata/telegraf/plugins/inputs/influxdb"
 	_ "github.com/influxdata/telegraf/plugins/inputs/jolokia"

plugins/inputs/http_response/README.md

@@ -0,0 +1,45 @@
+# Example Input Plugin
+
+This input plugin will test HTTP/HTTPS connections.
+
+### Configuration:
+
+```
+# List of UDP/TCP connections you want to check
+[[inputs.http_response]]
+  ## Server address (default http://localhost)
+  address = "http://github.com"
+  ## Set response_timeout (default 10 seconds)
+  response_timeout = 10
+  ## HTTP Request Method
+  method = "GET"
+  ## HTTP Request Headers
+  headers = '''
+  Host: github.com
+  '''
+  ## Whether to follow redirects from the server (defaults to false)
+  follow_redirects = true
+  ## Optional HTTP Request Body
+  body = '''
+  {'fake':'data'}
+  '''
+```
+
+### Measurements & Fields:
+
+- http_response
+    - response_time (float, seconds)
+    - http_response_code (int) #The code received
+
+### Tags:
+
+- All measurements have the following tags:
+    - server
+    - method
+
+### Example Output:
+
+```
+$ ./telegraf -config telegraf.conf -input-filter http_response -test
+http_response,method=GET,server=http://www.github.com http_response_code=200i,response_time=6.223266528 1459419354977857955
+```

plugins/inputs/http_response/http_response.go

@@ -0,0 +1,162 @@
+package http_response
+
+import (
+	"bufio"
+	"errors"
+	"io"
+	"net/http"
+	"net/textproto"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/plugins/inputs"
+)
+
+// HTTPResponse struct
+type HTTPResponse struct {
+	Address         string
+	Body            string
+	Method          string
+	ResponseTimeout int
+	Headers         string
+	FollowRedirects bool
+}
+
+// Description returns the plugin Description
+func (h *HTTPResponse) Description() string {
+	return "HTTP/HTTPS request given an address a method and a timeout"
+}
+
+var sampleConfig = `
+  ## Server address (default http://localhost)
+  address = "http://github.com"
+  ## Set response_timeout (default 10 seconds)
+  response_timeout = 10
+  ## HTTP Request Method
+  method = "GET"
+  ## HTTP Request Headers
+  headers = '''
+  Host: github.com
+  '''
+  ## Whether to follow redirects from the server (defaults to false)
+  follow_redirects = true
+  ## Optional HTTP Request Body
+  body = '''
+  {'fake':'data'}
+  '''
+`
+
+// SampleConfig returns the plugin SampleConfig
+func (h *HTTPResponse) SampleConfig() string {
+	return sampleConfig
+}
+
+// ErrRedirectAttempted indicates that a redirect occurred
+var ErrRedirectAttempted = errors.New("redirect")
+
+// CreateHttpClient creates an http client which will timeout at the specified
+// timeout period and can follow redirects if specified
+func CreateHttpClient(followRedirects bool, ResponseTimeout time.Duration) *http.Client {
+	client := &http.Client{
+		Timeout: time.Second * ResponseTimeout,
+	}
+
+	if followRedirects == false {
+		client.CheckRedirect = func(req *http.Request, via []*http.Request) error {
+			return ErrRedirectAttempted
+		}
+	}
+	return client
+}
+
+// ParseHeaders takes a string of newline seperated http headers and returns a
+// http.Header object. An error is returned if the headers cannot be parsed.
+func ParseHeaders(headers string) (http.Header, error) {
+	headers = strings.TrimSpace(headers) + "\n\n"
+	reader := bufio.NewReader(strings.NewReader(headers))
+	tp := textproto.NewReader(reader)
+	mimeHeader, err := tp.ReadMIMEHeader()
+	if err != nil {
+		return nil, err
+	}
+	return http.Header(mimeHeader), nil
+}
+
+// HTTPGather gathers all fields and returns any errors it encounters
+func (h *HTTPResponse) HTTPGather() (map[string]interface{}, error) {
+	// Prepare fields
+	fields := make(map[string]interface{})
+
+	client := CreateHttpClient(h.FollowRedirects, time.Duration(h.ResponseTimeout))
+
+	var body io.Reader
+	if h.Body != "" {
+		body = strings.NewReader(h.Body)
+	}
+	request, err := http.NewRequest(h.Method, h.Address, body)
+	if err != nil {
+		return nil, err
+	}
+	request.Header, err = ParseHeaders(h.Headers)
+	if err != nil {
+		return nil, err
+	}
+	// Start Timer
+	start := time.Now()
+	resp, err := client.Do(request)
+	if err != nil {
+		if h.FollowRedirects {
+			return nil, err
+		}
+		if urlError, ok := err.(*url.Error); ok &&
+			urlError.Err == ErrRedirectAttempted {
+			err = nil
+		} else {
+			return nil, err
+		}
+	}
+	fields["response_time"] = time.Since(start).Seconds()
+	fields["http_response_code"] = resp.StatusCode
+	return fields, nil
+}
+
+// Gather gets all metric fields and tags and returns any errors it encounters
+func (h *HTTPResponse) Gather(acc telegraf.Accumulator) error {
+	// Set default values
+	if h.ResponseTimeout < 1 {
+		h.ResponseTimeout = 10
+	}
+	// Check send and expected string
+	if h.Method == "" {
+		h.Method = "GET"
+	}
+	if h.Address == "" {
+		h.Address = "http://localhost"
+	}
+	addr, err := url.Parse(h.Address)
+	if err != nil {
+		return err
+	}
+	if addr.Scheme != "http" && addr.Scheme != "https" {
+		return errors.New("Only http and https are supported")
+	}
+	// Prepare data
+	tags := map[string]string{"server": h.Address, "method": h.Method}
+	var fields map[string]interface{}
+	// Gather data
+	fields, err = h.HTTPGather()
+	if err != nil {
+		return err
+	}
+	// Add metrics
+	acc.AddFields("http_response", fields, tags)
+	return nil
+}
+
+func init() {
+	inputs.Add("http_response", func() telegraf.Input {
+		return &HTTPResponse{}
+	})
+}