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Diffstat (limited to '')
-rw-r--r-- | src/go/collectors/go.d.plugin/modules/powerdns_recursor/collect.go | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/modules/powerdns_recursor/collect.go b/src/go/collectors/go.d.plugin/modules/powerdns_recursor/collect.go new file mode 100644 index 000000000..ec2e99c90 --- /dev/null +++ b/src/go/collectors/go.d.plugin/modules/powerdns_recursor/collect.go @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +package powerdns_recursor + +import ( + "encoding/json" + "errors" + "fmt" + "io" + "net/http" + "strconv" + + "github.com/netdata/netdata/go/go.d.plugin/pkg/web" +) + +const ( + urlPathLocalStatistics = "/api/v1/servers/localhost/statistics" +) + +func (r *Recursor) collect() (map[string]int64, error) { + statistics, err := r.scrapeStatistics() + if err != nil { + return nil, err + } + + collected := make(map[string]int64) + + r.collectStatistics(collected, statistics) + + if !isPowerDNSRecursorMetrics(collected) { + return nil, errors.New("returned metrics aren't PowerDNS Recursor metrics") + } + + return collected, nil +} + +func isPowerDNSRecursorMetrics(collected map[string]int64) bool { + // PowerDNS Authoritative Server has same endpoint and returns data in the same format. + _, ok1 := collected["over-capacity-drops"] + _, ok2 := collected["tcp-questions"] + return ok1 && ok2 +} + +func (r *Recursor) collectStatistics(collected map[string]int64, statistics statisticMetrics) { + for _, s := range statistics { + // https://doc.powerdns.com/authoritative/http-api/statistics.html#statisticitem + if s.Type != "StatisticItem" { + continue + } + + value, ok := s.Value.(string) + if !ok { + r.Debugf("%s value (%v) unexpected type: want=string, got=%T.", s.Name, s.Value, s.Value) + continue + } + + v, err := strconv.ParseInt(value, 10, 64) + if err != nil { + r.Debugf("%s value (%v) parse error: %v", s.Name, s.Value, err) + continue + } + + collected[s.Name] = v + } +} + +func (r *Recursor) scrapeStatistics() ([]statisticMetric, error) { + req, _ := web.NewHTTPRequest(r.Request) + req.URL.Path = urlPathLocalStatistics + + var statistics statisticMetrics + if err := r.doOKDecode(req, &statistics); err != nil { + return nil, err + } + + return statistics, nil +} + +func (r *Recursor) doOKDecode(req *http.Request, in interface{}) error { + resp, err := r.httpClient.Do(req) + if err != nil { + return fmt.Errorf("error on HTTP request '%s': %v", req.URL, err) + } + defer closeBody(resp) + + if resp.StatusCode != http.StatusOK { + return fmt.Errorf("'%s' returned HTTP status code: %d", req.URL, resp.StatusCode) + } + + if err := json.NewDecoder(resp.Body).Decode(in); err != nil { + return fmt.Errorf("error on decoding response from '%s': %v", req.URL, err) + } + return nil +} + +func closeBody(resp *http.Response) { + if resp != nil && resp.Body != nil { + _, _ = io.Copy(io.Discard, resp.Body) + _ = resp.Body.Close() + } +} |