telegraf/plugins/outputs/file/file.go

112 lines
2.2 KiB
Go

package file
import (
"fmt"
"io"
"os"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/plugins/serializers"
"github.com/influxdata/telegraf/registry/outputs"
)
type File struct {
Files []string
writer io.Writer
closers []io.Closer
serializer serializers.Serializer
}
var sampleConfig = `
## Files to write to, "stdout" is a specially handled file.
files = ["stdout", "/tmp/metrics.out"]
## Data format to output.
## Each data format has it's own unique set of configuration options, read
## more about them here:
## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_OUTPUT.md
data_format = "influx"
`
func (f *File) SetSerializer(serializer serializers.Serializer) {
f.serializer = serializer
}
func (f *File) Connect() error {
writers := []io.Writer{}
if len(f.Files) == 0 {
f.Files = []string{"stdout"}
}
for _, file := range f.Files {
if file == "stdout" {
writers = append(writers, os.Stdout)
f.closers = append(f.closers, os.Stdout)
} else {
var of *os.File
var err error
if _, err := os.Stat(file); os.IsNotExist(err) {
of, err = os.Create(file)
} else {
of, err = os.OpenFile(file, os.O_APPEND|os.O_WRONLY, os.ModeAppend)
}
if err != nil {
return err
}
writers = append(writers, of)
f.closers = append(f.closers, of)
}
}
f.writer = io.MultiWriter(writers...)
return nil
}
func (f *File) Close() error {
var errS string
for _, c := range f.closers {
if err := c.Close(); err != nil {
errS += err.Error() + "\n"
}
}
if errS != "" {
return fmt.Errorf(errS)
}
return nil
}
func (f *File) SampleConfig() string {
return sampleConfig
}
func (f *File) Description() string {
return "Send telegraf metrics to file(s)"
}
func (f *File) Write(metrics []telegraf.Metric) error {
if len(metrics) == 0 {
return nil
}
for _, metric := range metrics {
b, err := f.serializer.Serialize(metric)
if err != nil {
return fmt.Errorf("failed to serialize message: %s", err)
}
_, err = f.writer.Write(b)
if err != nil {
return fmt.Errorf("failed to write message: %s, %s", metric.Serialize(), err)
}
}
return nil
}
func init() {
outputs.Add("file", func() telegraf.Output {
return &File{}
})
}