func allTagValues(r *pstore.Record) map[string]opentsdb.TagValue {
result := map[string]opentsdb.TagValue{
kHostName: opentsdb.TagValue(r.HostName),
}
for k, v := range r.Tags {
result[k] = opentsdb.TagValue(v)
}
return result
}
func (w *writer) Write(records []pstore.Record) (err error) {
reqs := make([]opentsdb.StoreSamplesRequest, len(records))
for i := range records {
v := kafka.ToFloat64(&records[i])
// We can't allow Infinity or NaN, so we do the best we can.
if math.IsInf(v, 1) {
v = math.MaxFloat64
} else if math.IsInf(v, -1) {
v = -math.MaxFloat64
} else if math.IsNaN(v) {
v = 0
}
reqs[i] = opentsdb.StoreSamplesRequest{
Metric: opentsdb.TagValue(records[i].Path),
// TODO: Milliseconds?
Timestamp: records[i].Timestamp.Unix(),
Value: v,
Tags: allTagValues(&records[i]),
}
}
u, err := url.Parse(w.url)
if err != nil {
return err
}
u.Path = putEndpoint
buf, err := json.Marshal(reqs)
if err != nil {
return err
}
resp, err := w.httpClient.Post(
u.String(),
contentTypeJSON,
bytes.NewBuffer(buf),
)
if err != nil {
return err
}
defer resp.Body.Close()
// API returns status code 204 for successful writes.
// http://opentsdb.net/docs/build/html/api_http/put.html
if resp.StatusCode == http.StatusNoContent {
return nil
}
// API returns status code 400 on error, encoding error details in the
// response content in JSON.
buf, err = ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
var r map[string]int
if err := json.Unmarshal(buf, &r); err != nil {
return err
}
return fmt.Errorf("failed to write %d samples to OpenTSDB, %d succeeded", r["failed"], r["success"])
}