/
helpers.go
69 lines (55 loc) · 1.51 KB
/
helpers.go
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package influxdb
import (
"errors"
"fmt"
"math"
"strconv"
"time"
"github.com/Polarishq/middleware/framework/log"
"github.com/declanshanaghy/bbqberry/models"
)
// QueryAverageTemperature retrieves the average temperature over the given period for the requested probe from InfluxDB
func QueryAverageTemperature(period time.Duration, probe int32) (*models.TemperatureReading, error) {
log.Debug("action=method_entry period=%s probe=%d", period, probe)
defer log.Debug("action=method_exit")
t := time.Now().Add(period * -1)
ts := t.Format(time.RFC3339)
tq := `SELECT MEAN(Celsius) as Celsius, MEAN(Fahrenheit) as Fahrenheit, MEAN(Kelvin) as Kelvin FROM temp WHERE Probe='%d' AND time > '%s'`
q := fmt.Sprintf(tq, probe, ts)
response, err := Query(q)
if err != nil {
return nil, err
}
toF := func(v interface{}) (int32, error) {
s := fmt.Sprintf("%v", v)
f, err := strconv.ParseFloat(s, 32)
if err == nil {
return int32(f), nil
}
return math.MaxInt32, err
}
if len(response.Results) > 0 && len(response.Results[0].Series) > 0 {
r := response.Results[0]
values := r.Series[0].Values[0]
c, err := toF(values[1])
if err != nil {
return nil, err
}
f, err := toF(values[2])
if err != nil {
return nil, err
}
k, err := toF(values[3])
if err != nil {
return nil, err
}
reading := models.TemperatureReading{
Probe: &probe,
Celsius: &c,
Fahrenheit: &f,
Kelvin: &k,
}
return &reading, nil
}
return nil, errors.New("No results returned from InfluxDB")
}