89 lines
2.2 KiB
Go
89 lines
2.2 KiB
Go
|
// Licensed to Elasticsearch B.V. under one or more contributor
|
||
|
|
// license agreements. See the NOTICE file distributed with
|
||
|
|
// this work for additional information regarding copyright
|
||
|
|
// ownership. Elasticsearch B.V. licenses this file to you under
|
||
|
|
// the Apache License, Version 2.0 (the "License"); you may
|
||
|
|
// not use this file except in compliance with the License.
|
||
|
|
// You may obtain a copy of the License at
|
||
|
|
//
|
||
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
//
|
||
|
|
// Unless required by applicable law or agreed to in writing,
|
||
|
|
// software distributed under the License is distributed on an
|
||
|
|
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
|
||
|
|
// KIND, either express or implied. See the License for the
|
||
|
|
// specific language governing permissions and limitations
|
||
|
|
// under the License.
|
||
|
|
|
||
|
|
package readfile
|
||
|
|
|
||
|
|
import (
|
||
|
|
"errors"
|
||
|
|
"time"
|
||
|
|
|
||
|
|
"github.com/elastic/beats/filebeat/reader"
|
||
|
|
)
|
||
|
|
|
||
|
|
var (
|
||
|
|
errTimeout = errors.New("timeout")
|
||
|
|
)
|
||
|
|
|
||
|
|
// timeoutProcessor will signal some configurable timeout error if no
|
||
|
|
// new line can be returned in time.
|
||
|
|
type TimeoutReader struct {
|
||
|
|
reader reader.Reader
|
||
|
|
timeout time.Duration
|
||
|
|
signal error
|
||
|
|
running bool
|
||
|
|
ch chan lineMessage
|
||
|
|
}
|
||
|
|
|
||
|
|
type lineMessage struct {
|
||
|
|
line reader.Message
|
||
|
|
err error
|
||
|
|
}
|
||
|
|
|
||
|
|
// New returns a new timeout reader from an input line reader.
|
||
|
|
func NewTimeoutReader(reader reader.Reader, signal error, t time.Duration) *TimeoutReader {
|
||
|
|
if signal == nil {
|
||
|
|
signal = errTimeout
|
||
|
|
}
|
||
|
|
|
||
|
|
return &TimeoutReader{
|
||
|
|
reader: reader,
|
||
|
|
signal: signal,
|
||
|
|
timeout: t,
|
||
|
|
ch: make(chan lineMessage, 1),
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Next returns the next line. If no line was returned before timeout, the
|
||
|
|
// configured timeout error is returned.
|
||
|
|
// For handline timeouts a goroutine is started for reading lines from
|
||
|
|
// configured line reader. Only when underlying reader returns an error, the
|
||
|
|
// goroutine will be finished.
|
||
|
|
func (r *TimeoutReader) Next() (reader.Message, error) {
|
||
|
|
if !r.running {
|
||
|
|
r.running = true
|
||
|
|
go func() {
|
||
|
|
for {
|
||
|
|
message, err := r.reader.Next()
|
||
|
|
r.ch <- lineMessage{message, err}
|
||
|
|
if err != nil {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}()
|
||
|
|
}
|
||
|
|
|
||
|
|
select {
|
||
|
|
case msg := <-r.ch:
|
||
|
|
if msg.err != nil {
|
||
|
|
r.running = false
|
||
|
|
}
|
||
|
|
return msg.line, msg.err
|
||
|
|
case <-time.After(r.timeout):
|
||
|
|
return reader.Message{}, r.signal
|
||
|
|
}
|
||
|
|
}
|