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|
package pipeline
import (
"bufio"
"fmt"
"io"
"regexp"
"strings"
"testing"
"time"
"context"
)
type RegexpFilter struct {
rx *regexp.Regexp
}
func NewRegexpFilter(rx *regexp.Regexp) *RegexpFilter {
return &RegexpFilter{
rx: rx,
}
}
func (rf *RegexpFilter) Accept(ctx context.Context, in chan interface{}, out ChanOutput) {
defer fmt.Println("END RegexpFilter.Accept")
defer out.SendEndMark("end of RegexpFilter")
for {
select {
case <-ctx.Done():
return
case v := <-in:
if err, ok := v.(error); ok {
if IsEndMark(err) {
return
}
}
if s, ok := v.(string); ok {
if rf.rx.MatchString(s) {
out.Send(s)
}
}
}
}
}
type LineFeeder struct {
lines []string
}
func NewLineFeeder(rdr io.Reader) *LineFeeder {
scan := bufio.NewScanner(rdr)
var lines []string
for scan.Scan() {
lines = append(lines, scan.Text())
}
return &LineFeeder{
lines: lines,
}
}
func (f *LineFeeder) Reset() {
}
func (f *LineFeeder) Start(ctx context.Context, out ChanOutput) {
fmt.Println("START LineFeeder.Start")
defer fmt.Println("END LineFeeder.Start")
defer out.SendEndMark("end of LineFeeder")
for _, s := range f.lines {
out.Send(s)
}
}
type Receiver struct {
lines []string
done chan struct{}
}
func NewReceiver() *Receiver {
r := &Receiver{}
r.Reset()
return r
}
func (r *Receiver) Reset() {
r.done = make(chan struct{})
r.lines = nil
}
func (r *Receiver) Done() <-chan struct{} {
return r.done
}
func (r *Receiver) Accept(ctx context.Context, in chan interface{}, out ChanOutput) {
defer fmt.Println("END Receiver.Accept")
defer close(r.done)
for {
select {
case <-ctx.Done():
return
case v := <-in:
if err, ok := v.(error); ok {
if IsEndMark(err) {
return
}
}
if s, ok := v.(string); ok {
r.lines = append(r.lines, s)
}
}
}
}
func TestPipeline(t *testing.T) {
src := NewLineFeeder(strings.NewReader(`foo
bar
foobar
barfoo
`))
n1 := NewRegexpFilter(regexp.MustCompile(`^foo`))
n2 := NewRegexpFilter(regexp.MustCompile(`bar$`))
dst := NewReceiver()
p := New()
p.SetSource(src)
p.Add(n1)
p.Add(n2)
p.SetDestination(dst)
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()
p.Run(ctx)
t.Logf("%#v", dst.lines)
}
|
