How to add a plugin to Telegraf?

Question

Hello I would to know if someone have all ready add a plugin to telegraf for Influxdb. I have my go code which is working. What do I need next and where to put theses files?

I've found that I need to do something like this:

type ReadFile struct {
    //buf []byte
    //MemoryBytes int64
   //PID int
}

func (s *ReadFile) Description() string {
   return "This is a test plugin to read data from a file and send them to influxdb" }

func (s *ReadFile) SampleConfig() string {
    return "ok = true # indicate if everything is fine"
}

func Gather(acc plugins.Accumulator) error {

     readFile(alarmFile)

    acc.Add("alarm", result_of_readFile_here, tags)
    }
  }

    func init() {
    plugins.Add("readFile", func() plugins.Plugin { &ReadFile{} })
 }

But is this my entire Go plugin or another file in Go to add with my Go program?

And where does the file.conf is store?

[tags]
dc = "alarm"

[agent]
interval = "10s"

# OUTPUTS
[outputs]
[outputs.influxdb]
url = "http://127.0.0.1:8086" # required.
database = "summer" # required.
precision = "s"

# PLUGINS
[readFile]

If you have a list of what I need, how to structure it, where I store file or maybe an example could be really helpful.

Thanks!!

Answer 1

-> I receive this, it gave me a better understanding, I think it could be helpful:

https://github.com/influxdata/telegraf/blob/master/CONTRIBUTING.md

"His plugin code looks good to go. He needs to place that file in $GOPATH/src/github.com/influxdata/telegraf/plugin/inputs/testPlugin/testPlugin.go

He should write a test for the plugin and place it at $GOPATH/src/github.com/influxdata/telegraf/plugin/inputs/testPlugin/testPlugin_test.go

After this is complete he needs to register the plugin at $GOPATH/src/github.com/influxdata/telegraf/plugin/inputs/all/all.go

Then he should run make from $GOPATH/src/github.com/influxdata/telegraf. This will place the new telegraf binary in $GOPATH/bin/telegraf.

Run the binary with the following flags to generate the valid configuration:

$GOPATH/bin/telegraf -sample-config -input-filter testPlugin -output-filter influxdb > testPlugin_config.conf

From there you can run the binary with the -test flag by passing it the sample config:

$GOPATH/bin/telegraf -config testPlugin_config.conf -test

This will output the line protocol that is to be inserted into the database."

-> And the testPlugin.go that he talks about:

package testPlugin

import (
    "time"
)

type ReadFile struct {
 counter int64
}

func (s *TestPlugin) Description() string {
  return "This is a test plugin to write data to influxdb with a plugin"
}

func (s *TestPlugin) SampleConfig() string {
  return "ok = true # indicate if everything is fine"
}

func Gather(acc telegraf.Accumulator) error {

c := time.Tick(10 * time.Second)
for now := range c {

    counter := counter + 1
    acc.Add("counter",counter, tags)
 }
} 

func init() {
  inputs.Add("testPlugin", func() telegraf.Input { return &TestPlugin{} })
}

Answer 2

There's an opened issue for external plugin support which might be part of Telegraf 1.4.0. If will probably load external *.so files.

Until then all plugins are supposed to be merged into master repository via PRs. There are already many plugins waiting in review process. This model is obviously not very scalable.