I am writing a custom beat to read temperature.
I have created the Beat using this, https://www.elastic.co/blog/build-your-own-beat, as an example.
However I am confused as to how to modify the fields.yml file so that the correct data types are set. I have tried adding the following to the fields.yml file in the root of my project:
- key: temperaturebeat
title: temperaturebeat
description:
fields:
- name: counter
type: long
required: true
description: >
PLEASE UPDATE DOCUMENTATION
- name: deviceid
type: string
- name: sensorid
type: string
- name: celcius
type: double
- name: farenheit
type: double
But each time I run male update the file is modified and these entries are removed. I have tried creating a file etc/fields.yml but the same thing happens.
My beat sort of works as it is, but the celcius measurement is seen as a long whereas the farehnheit is seen as a float. As you can see from the above I want them both to be double.
The following is how I am reading the values
func (bt *Temperaturebeat) readThermometers(dirFile string, beatname string, deviceid string) {
// Build the pattern for the glob
pattern := fmt.Sprintf("%s/??-????????????", dirFile)
// Find all the files that have the specified pattern
files, _ := filepath.Glob(pattern)
for _, thermo := range files {
// Create the path to the file from which to read the value
thermoFile := fmt.Sprintf("%s/w1_slave", thermo)
// get the C and F
temperatureC, temperatureF := temperature(thermoFile)
event := common.MapStr{
"@timestamp": common.Time(time.Now()),
"type": beatname,
"deviceid": deviceid,
"sensorid": path.Base(thermo),
"celcius": temperatureC,
"farenheit": temperatureF,
}
bt.client.PublishEvent(event)
}
}
func temperature(file string) (float64, float64) {
// Read the data in from the device
dataBytes, err := ioutil.ReadFile(file)
check(err)
data := string(dataBytes)
// Get the value of the temperature from the device
result := regexTemp.FindStringSubmatch(data)
tempFloat, err := strconv.ParseFloat(result[1], 64)
check(err)
// determine the C and F
celcius := tempFloat / 1000
farenheit := celcius*1.8 + 32
return celcius, farenheit
}
The beat is configured to output to logstash if that makes any difference.
Any help is gratefully received.
Thanks, Russell