storj/cmd/statreceiver/graphite.go
JT Olio 362f447d9f
cmd/statreceiver: lua-scriptable stat receiver (#636)
* cmd/statreceiver: lua-scriptable stat receiver

Change-Id: I3ce0fe3f1ef4b1f4f27eed90bac0e91cfecf22d7

* some updates

Change-Id: I7c3485adcda1278fce01ae077b4761b3ddb9fb7a

* more comments

Change-Id: I0bb22993cd934c3d40fc1da80d07e49e686b80dd

* linter fixes

Change-Id: Ied014304ecb9aadcf00a6b66ad28f856a428d150

* catch errors

Change-Id: I6e1920f1fd941e66199b30bc427285c19769fc70

* review feedback

Change-Id: I9d4051851eab18970c5f5ddcf4ff265508e541d3

* errorgroup improvements

Change-Id: I4699dda3022f0485fbb50c9dafe692d3921734ff

* too tricky

the previous thing was better for memory with lots of errors at a time
but https://play.golang.org/p/RweTMRjoSCt is too much of a foot gun

Change-Id: I23f0b3d77dd4288fcc20b3756a7110359576bf44
2018-12-11 11:24:31 -07:00

82 lines
1.6 KiB
Go

// Copyright (C) 2018 Storj Labs, Inc.
// See LICENSE for copying information.
package main
import (
"bufio"
"fmt"
"log"
"net"
"sync"
"time"
)
// GraphiteDest is a MetricDest that sends data with the Graphite TCP wire
// protocol
type GraphiteDest struct {
mtx sync.Mutex
address string
conn net.Conn
buf *bufio.Writer
stopped bool
}
// NewGraphiteDest creates a GraphiteDest with TCP address address. Because
// this function is called in a Lua pipeline domain-specific language, the DSL
// wants a graphite destination to be flushing every few seconds, so this
// constructor will start that process. Use Close to stop it.
func NewGraphiteDest(address string) *GraphiteDest {
rv := &GraphiteDest{address: address}
go rv.flush()
return rv
}
// Metric implements MetricDest
func (d *GraphiteDest) Metric(application, instance string,
key []byte, val float64, ts time.Time) error {
d.mtx.Lock()
defer d.mtx.Unlock()
if d.conn == nil {
conn, err := net.Dial("tcp", d.address)
if err != nil {
return err
}
d.conn = conn
d.buf = bufio.NewWriter(conn)
}
_, err := fmt.Fprintf(d.buf, "%s.%s.%s %v %d\n", application, string(key),
instance, val, ts.Unix())
return err
}
// Close stops the flushing goroutine
func (d *GraphiteDest) Close() error {
d.mtx.Lock()
d.stopped = true
d.mtx.Unlock()
return nil
}
func (d *GraphiteDest) flush() {
for {
time.Sleep(5 * time.Second)
d.mtx.Lock()
if d.stopped {
d.mtx.Unlock()
return
}
var err error
if d.buf != nil {
err = d.buf.Flush()
}
d.mtx.Unlock()
if err != nil {
log.Printf("failed flushing: %v", err)
}
}
}