telegraf/plugins/parsers/influx/parser.go

114 lines
2.0 KiB
Go

package influx
import (
"errors"
"fmt"
"github.com/influxdata/telegraf"
)
const (
maxErrorBufferSize = 1024
)
var (
ErrNoMetric = errors.New("no metric in line")
)
type Handler interface {
SetMeasurement(name []byte)
AddTag(key []byte, value []byte)
AddInt(key []byte, value []byte)
AddUint(key []byte, value []byte)
AddFloat(key []byte, value []byte)
AddString(key []byte, value []byte)
AddBool(key []byte, value []byte)
SetTimestamp(tm []byte)
Reset()
}
type ParseError struct {
Offset int
msg string
buf string
}
func (e *ParseError) Error() string {
buffer := e.buf
if len(buffer) > maxErrorBufferSize {
buffer = buffer[:maxErrorBufferSize] + "..."
}
return fmt.Sprintf("metric parse error: %s at offset %d: %q", e.msg, e.Offset, buffer)
}
type Parser struct {
DefaultTags map[string]string
*machine
handler *MetricHandler
}
func NewParser(handler *MetricHandler) *Parser {
return &Parser{
machine: NewMachine(handler),
handler: handler,
}
}
func (p *Parser) Parse(input []byte) ([]telegraf.Metric, error) {
metrics := make([]telegraf.Metric, 0)
p.machine.SetData(input)
for p.machine.ParseLine() {
err := p.machine.Err()
if err != nil {
return nil, &ParseError{
Offset: p.machine.Position(),
msg: err.Error(),
buf: string(input),
}
}
metric, err := p.handler.Metric()
if err != nil {
return nil, err
}
p.handler.Reset()
metrics = append(metrics, metric)
}
p.applyDefaultTags(metrics)
return metrics, nil
}
func (p *Parser) ParseLine(line string) (telegraf.Metric, error) {
metrics, err := p.Parse([]byte(line + "\n"))
if err != nil {
return nil, err
}
if len(metrics) < 1 {
return nil, ErrNoMetric
}
return metrics[0], nil
}
func (p *Parser) SetDefaultTags(tags map[string]string) {
p.DefaultTags = tags
}
func (p *Parser) applyDefaultTags(metrics []telegraf.Metric) {
if len(p.DefaultTags) == 0 {
return
}
for _, m := range metrics {
for k, v := range p.DefaultTags {
if !m.HasTag(k) {
m.AddTag(k, v)
}
}
}
}