forked from influxdata/telegraf
-
Notifications
You must be signed in to change notification settings - Fork 0
/
http_response.go
381 lines (320 loc) · 9.44 KB
/
http_response.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
package http_response
import (
"errors"
"fmt"
"io"
"io/ioutil"
"log"
"net"
"net/http"
"net/url"
"regexp"
"strconv"
"strings"
"time"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/internal"
"github.com/influxdata/telegraf/internal/tls"
"github.com/influxdata/telegraf/plugins/inputs"
)
// HTTPResponse struct
type HTTPResponse struct {
Address string // deprecated in 1.12
URLs []string `toml:"urls"`
HTTPProxy string `toml:"http_proxy"`
Body string
Method string
ResponseTimeout internal.Duration
Headers map[string]string
FollowRedirects bool
ResponseStringMatch string
Interface string
tls.ClientConfig
compiledStringMatch *regexp.Regexp
client *http.Client
}
// Description returns the plugin Description
func (h *HTTPResponse) Description() string {
return "HTTP/HTTPS request given an address a method and a timeout"
}
var sampleConfig = `
## Deprecated in 1.12, use 'urls'
## Server address (default http://localhost)
# address = "http://localhost"
## List of urls to query.
# urls = ["http://localhost"]
## Set http_proxy (telegraf uses the system wide proxy settings if it's is not set)
# http_proxy = "http://localhost:8888"
## Set response_timeout (default 5 seconds)
# response_timeout = "5s"
## HTTP Request Method
# method = "GET"
## Whether to follow redirects from the server (defaults to false)
# follow_redirects = false
## Optional HTTP Request Body
# body = '''
# {'fake':'data'}
# '''
## Optional substring or regex match in body of the response
# response_string_match = "\"service_status\": \"up\""
# response_string_match = "ok"
# response_string_match = "\".*_status\".?:.?\"up\""
## Optional TLS Config
# tls_ca = "/etc/telegraf/ca.pem"
# tls_cert = "/etc/telegraf/cert.pem"
# tls_key = "/etc/telegraf/key.pem"
## Use TLS but skip chain & host verification
# insecure_skip_verify = false
## HTTP Request Headers (all values must be strings)
# [inputs.http_response.headers]
# Host = "github.com"
## Interface to use when dialing an address
# interface = "eth0"
`
// SampleConfig returns the plugin SampleConfig
func (h *HTTPResponse) SampleConfig() string {
return sampleConfig
}
// ErrRedirectAttempted indicates that a redirect occurred
var ErrRedirectAttempted = errors.New("redirect")
// Set the proxy. A configured proxy overwrites the system wide proxy.
func getProxyFunc(http_proxy string) func(*http.Request) (*url.URL, error) {
if http_proxy == "" {
return http.ProxyFromEnvironment
}
proxyURL, err := url.Parse(http_proxy)
if err != nil {
return func(_ *http.Request) (*url.URL, error) {
return nil, errors.New("bad proxy: " + err.Error())
}
}
return func(r *http.Request) (*url.URL, error) {
return proxyURL, nil
}
}
// createHttpClient creates an http client which will timeout at the specified
// timeout period and can follow redirects if specified
func (h *HTTPResponse) createHttpClient() (*http.Client, error) {
tlsCfg, err := h.ClientConfig.TLSConfig()
if err != nil {
return nil, err
}
dialer := &net.Dialer{}
if h.Interface != "" {
dialer.LocalAddr, err = localAddress(h.Interface)
if err != nil {
return nil, err
}
}
client := &http.Client{
Transport: &http.Transport{
Proxy: getProxyFunc(h.HTTPProxy),
DialContext: dialer.DialContext,
DisableKeepAlives: true,
TLSClientConfig: tlsCfg,
},
Timeout: h.ResponseTimeout.Duration,
}
if h.FollowRedirects == false {
client.CheckRedirect = func(req *http.Request, via []*http.Request) error {
return ErrRedirectAttempted
}
}
return client, nil
}
func localAddress(interfaceName string) (net.Addr, error) {
i, err := net.InterfaceByName(interfaceName)
if err != nil {
return nil, err
}
addrs, err := i.Addrs()
if err != nil {
return nil, err
}
for _, addr := range addrs {
if naddr, ok := addr.(*net.IPNet); ok {
// leaving port set to zero to let kernel pick
return &net.TCPAddr{IP: naddr.IP}, nil
}
}
return nil, fmt.Errorf("cannot create local address for interface %q", interfaceName)
}
func setResult(result_string string, fields map[string]interface{}, tags map[string]string) {
result_codes := map[string]int{
"success": 0,
"response_string_mismatch": 1,
"body_read_error": 2,
"connection_failed": 3,
"timeout": 4,
"dns_error": 5,
}
tags["result"] = result_string
fields["result_type"] = result_string
fields["result_code"] = result_codes[result_string]
}
func setError(err error, fields map[string]interface{}, tags map[string]string) error {
if timeoutError, ok := err.(net.Error); ok && timeoutError.Timeout() {
setResult("timeout", fields, tags)
return timeoutError
}
urlErr, isUrlErr := err.(*url.Error)
if !isUrlErr {
return nil
}
opErr, isNetErr := (urlErr.Err).(*net.OpError)
if isNetErr {
switch e := (opErr.Err).(type) {
case (*net.DNSError):
setResult("dns_error", fields, tags)
return e
case (*net.ParseError):
// Parse error has to do with parsing of IP addresses, so we
// group it with address errors
setResult("address_error", fields, tags)
return e
}
}
return nil
}
// HTTPGather gathers all fields and returns any errors it encounters
func (h *HTTPResponse) httpGather(u string) (map[string]interface{}, map[string]string, error) {
// Prepare fields and tags
fields := make(map[string]interface{})
tags := map[string]string{"server": u, "method": h.Method}
var body io.Reader
if h.Body != "" {
body = strings.NewReader(h.Body)
}
request, err := http.NewRequest(h.Method, u, body)
if err != nil {
return nil, nil, err
}
for key, val := range h.Headers {
request.Header.Add(key, val)
if key == "Host" {
request.Host = val
}
}
// Start Timer
start := time.Now()
resp, err := h.client.Do(request)
response_time := time.Since(start).Seconds()
// If an error in returned, it means we are dealing with a network error, as
// HTTP error codes do not generate errors in the net/http library
if err != nil {
// Log error
log.Printf("D! Network error while polling %s: %s", u, err.Error())
// Get error details
netErr := setError(err, fields, tags)
// If recognize the returnded error, get out
if netErr != nil {
return fields, tags, nil
}
// Any error not recognized by `set_error` is considered a "connection_failed"
setResult("connection_failed", fields, tags)
// If the error is a redirect we continue processing and log the HTTP code
urlError, isUrlError := err.(*url.Error)
if !h.FollowRedirects && isUrlError && urlError.Err == ErrRedirectAttempted {
err = nil
} else {
// If the error isn't a timeout or a redirect stop
// processing the request
return fields, tags, nil
}
}
if _, ok := fields["response_time"]; !ok {
fields["response_time"] = response_time
}
// This function closes the response body, as
// required by the net/http library
defer resp.Body.Close()
// Set log the HTTP response code
tags["status_code"] = strconv.Itoa(resp.StatusCode)
fields["http_response_code"] = resp.StatusCode
bodyBytes, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Printf("D! Failed to read body of HTTP Response : %s", err)
setResult("body_read_error", fields, tags)
fields["content_length"] = len(bodyBytes)
if h.ResponseStringMatch != "" {
fields["response_string_match"] = 0
}
return fields, tags, nil
}
fields["content_length"] = len(bodyBytes)
// Check the response for a regex match.
if h.ResponseStringMatch != "" {
if h.compiledStringMatch.Match(bodyBytes) {
setResult("success", fields, tags)
fields["response_string_match"] = 1
} else {
setResult("response_string_mismatch", fields, tags)
fields["response_string_match"] = 0
}
} else {
setResult("success", fields, tags)
}
return fields, tags, nil
}
// Gather gets all metric fields and tags and returns any errors it encounters
func (h *HTTPResponse) Gather(acc telegraf.Accumulator) error {
// Compile the body regex if it exist
if h.compiledStringMatch == nil {
var err error
h.compiledStringMatch, err = regexp.Compile(h.ResponseStringMatch)
if err != nil {
return fmt.Errorf("Failed to compile regular expression %s : %s", h.ResponseStringMatch, err)
}
}
// Set default values
if h.ResponseTimeout.Duration < time.Second {
h.ResponseTimeout.Duration = time.Second * 5
}
// Check send and expected string
if h.Method == "" {
h.Method = "GET"
}
if len(h.URLs) == 0 {
if h.Address == "" {
h.URLs = []string{"http://localhost"}
} else {
log.Printf("W! [inputs.http_response] 'address' deprecated in telegraf 1.12, please use 'urls'")
h.URLs = []string{h.Address}
}
}
if h.client == nil {
client, err := h.createHttpClient()
if err != nil {
return err
}
h.client = client
}
for _, u := range h.URLs {
addr, err := url.Parse(u)
if err != nil {
acc.AddError(err)
continue
}
if addr.Scheme != "http" && addr.Scheme != "https" {
acc.AddError(errors.New("Only http and https are supported"))
continue
}
// Prepare data
var fields map[string]interface{}
var tags map[string]string
// Gather data
fields, tags, err = h.httpGather(u)
if err != nil {
acc.AddError(err)
continue
}
// Add metrics
acc.AddFields("http_response", fields, tags)
}
return nil
}
func init() {
inputs.Add("http_response", func() telegraf.Input {
return &HTTPResponse{}
})
}