Files
2020-05-03 18:15:31 +10:00

120 lines
3.1 KiB
Go

package metrics
import (
"encoding/json"
"fmt"
"log"
"path/filepath"
"strconv"
"github.com/eclipse/paho.mqtt.golang"
"github.com/hikhvar/mqtt2prometheus/pkg/config"
"github.com/prometheus/client_golang/prometheus"
)
type Ingest struct {
validMetrics map[string]config.MetricConfig
collector Collector
MessageMetric *prometheus.CounterVec
}
func NewIngest(collector Collector, metrics []config.MetricConfig) *Ingest {
valid := make(map[string]config.MetricConfig)
for i := range metrics {
key := metrics[i].MQTTName
valid[key] = metrics[i]
}
return &Ingest{
validMetrics: valid,
collector: collector,
MessageMetric: prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "received_messages",
Help: "received messages per topic and status",
}, []string{"status", "topic"},
),
}
}
type MQTTPayload map[string]interface{}
func (i *Ingest) store(deviceID string, rawMetrics MQTTPayload) error {
var mc MetricCollection
for metricName, value := range rawMetrics {
cfg, cfgFound := i.validMetrics[metricName]
if !cfgFound {
continue
}
var metricValue float64
if boolValue, ok := value.(bool); ok {
if boolValue {
metricValue = 1
} else {
metricValue = 0
}
} else if strValue, ok := value.(string); ok {
// If string value mapping is defined, use that
if cfg.StringValueMapping != nil {
floatValue, ok := cfg.StringValueMapping.Map[strValue]
if ok {
metricValue = floatValue
} else if cfg.StringValueMapping.ErrorValue != nil {
metricValue = *cfg.StringValueMapping.ErrorValue
} else {
return fmt.Errorf("got unexpected string data '%s'", strValue)
}
} else {
// otherwise try to parse float
floatValue, err := strconv.ParseFloat(strValue, 64)
if err != nil {
return fmt.Errorf("got data with unexpectd type: %T ('%s') and failed to parse to float", value, value)
}
metricValue = floatValue
}
} else if floatValue, ok := value.(float64); ok {
metricValue = floatValue
} else {
return fmt.Errorf("got data with unexpectd type: %T ('%s')", value, value)
}
mc = append(mc, Metric{
Description: cfg.PrometheusDescription(),
Value: metricValue,
ValueType: cfg.PrometheusValueType(),
})
}
i.collector.Observe(deviceID, mc)
return nil
}
func (i *Ingest) SetupSubscriptionHandler(errChan chan<- error) mqtt.MessageHandler {
return func(c mqtt.Client, m mqtt.Message) {
log.Printf("Got message '%s' on topic %s\n", string(m.Payload()), m.Topic())
deviceId := filepath.Base(m.Topic())
var rawMetrics MQTTPayload
err := json.Unmarshal(m.Payload(), &rawMetrics)
if err != nil {
errChan <- fmt.Errorf("could not decode message '%s' on topic %s: %s", string(m.Payload()), m.Topic(), err.Error())
i.MessageMetric.WithLabelValues("decodeError", m.Topic()).Desc()
return
}
err = i.store(deviceId, rawMetrics)
if err != nil {
errChan <- fmt.Errorf("could not store metrics '%s' on topic %s: %s", string(m.Payload()), m.Topic(), err.Error())
i.MessageMetric.WithLabelValues("storeError", m.Topic()).Inc()
return
}
i.MessageMetric.WithLabelValues("success", m.Topic()).Inc()
}
}