package prometheus import ( "errors" "fmt" "io/ioutil" "net" "net/http" "sync" "time" "github.com/influxdata/telegraf" "github.com/influxdata/telegraf/internal" "github.com/influxdata/telegraf/plugins/inputs" ) const acceptHeader = `application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited;q=0.7,text/plain;version=0.0.4;q=0.3` type Prometheus struct { Urls []string // Bearer Token authorization file path BearerToken string `toml:"bearer_token"` ResponseTimeout internal.Duration `toml:"response_timeout"` // Path to CA file SSLCA string `toml:"ssl_ca"` // Path to host cert file SSLCert string `toml:"ssl_cert"` // Path to cert key file SSLKey string `toml:"ssl_key"` // Use SSL but skip chain & host verification InsecureSkipVerify bool } var sampleConfig = ` ## An array of urls to scrape metrics from. urls = ["http://localhost:9100/metrics"] ## Use bearer token for authorization # bearer_token = /path/to/bearer/token ## Specify timeout duration for slower prometheus clients (default is 3s) # response_timeout = "3s" ## Optional SSL Config # ssl_ca = /path/to/cafile # ssl_cert = /path/to/certfile # ssl_key = /path/to/keyfile ## Use SSL but skip chain & host verification # insecure_skip_verify = false ` func (p *Prometheus) SampleConfig() string { return sampleConfig } func (p *Prometheus) Description() string { return "Read metrics from one or many prometheus clients" } var ErrProtocolError = errors.New("prometheus protocol error") // Reads stats from all configured servers accumulates stats. // Returns one of the errors encountered while gather stats (if any). func (p *Prometheus) Gather(acc telegraf.Accumulator) error { var wg sync.WaitGroup var outerr error for _, serv := range p.Urls { wg.Add(1) go func(serv string) { defer wg.Done() outerr = p.gatherURL(serv, acc) }(serv) } wg.Wait() return outerr } var tr = &http.Transport{ ResponseHeaderTimeout: time.Duration(3 * time.Second), } var client = &http.Client{ Transport: tr, Timeout: time.Duration(4 * time.Second), } func (p *Prometheus) gatherURL(url string, acc telegraf.Accumulator) error { var req, err = http.NewRequest("GET", url, nil) req.Header.Add("Accept", acceptHeader) var token []byte var resp *http.Response tlsCfg, err := internal.GetTLSConfig( p.SSLCert, p.SSLKey, p.SSLCA, p.InsecureSkipVerify) if err != nil { return err } var rt http.RoundTripper = &http.Transport{ Dial: (&net.Dialer{ Timeout: 5 * time.Second, KeepAlive: 30 * time.Second, }).Dial, TLSHandshakeTimeout: 5 * time.Second, TLSClientConfig: tlsCfg, ResponseHeaderTimeout: p.ResponseTimeout.Duration, DisableKeepAlives: true, } if p.BearerToken != "" { token, err = ioutil.ReadFile(p.BearerToken) if err != nil { return err } req.Header.Set("Authorization", "Bearer "+string(token)) } resp, err = rt.RoundTrip(req) if err != nil { return fmt.Errorf("error making HTTP request to %s: %s", url, err) } defer resp.Body.Close() if resp.StatusCode != http.StatusOK { return fmt.Errorf("%s returned HTTP status %s", url, resp.Status) } body, err := ioutil.ReadAll(resp.Body) if err != nil { return fmt.Errorf("error reading body: %s", err) } metrics, err := Parse(body, resp.Header) if err != nil { return fmt.Errorf("error reading metrics for %s: %s", url, err) } // Add (or not) collected metrics for _, metric := range metrics { tags := metric.Tags() tags["url"] = url acc.AddFields(metric.Name(), metric.Fields(), tags, metric.Time()) } return nil } func init() { inputs.Add("prometheus", func() telegraf.Input { return &Prometheus{ResponseTimeout: internal.Duration{Duration: time.Second * 3}} }) }