syft/internal/ui/etui/ephemeral_tui.go

129 lines
3.0 KiB
Go

package etui
import (
"bytes"
"context"
"fmt"
"os"
"sync"
"github.com/anchore/syft/internal/logger"
"github.com/anchore/syft/internal/ui/common"
"github.com/anchore/syft/ui"
"github.com/anchore/syft/internal/log"
syftEvent "github.com/anchore/syft/syft/event"
"github.com/wagoodman/go-partybus"
"github.com/wagoodman/jotframe/pkg/frame"
)
// TODO: specify per-platform implementations with build tags
func setupScreen(output *os.File) *frame.Frame {
config := frame.Config{
PositionPolicy: frame.PolicyFloatForward,
// only report output to stderr, reserve report output for stdout
Output: output,
}
fr, err := frame.New(config)
if err != nil {
log.Errorf("failed to create screen object: %+v", err)
return nil
}
return fr
}
// nolint:funlen,gocognit
func OutputToEphemeralTUI(workerErrs <-chan error, subscription *partybus.Subscription) error {
output := os.Stderr
// prep the logger to not clobber the screen from now on (logrus only)
logBuffer := bytes.NewBufferString("")
logWrapper, ok := log.Log.(*logger.LogrusLogger)
if ok {
logWrapper.Logger.SetOutput(logBuffer)
}
// hide cursor
_, _ = fmt.Fprint(output, "\x1b[?25l")
// show cursor
defer fmt.Fprint(output, "\x1b[?25h")
fr := setupScreen(output)
if fr == nil {
return fmt.Errorf("unable to setup screen")
}
var isClosed bool
defer func() {
if !isClosed {
fr.Close()
frame.Close()
// flush any errors to the screen before the report
fmt.Fprint(output, logBuffer.String())
}
logWrapper, ok := log.Log.(*logger.LogrusLogger)
if ok {
logWrapper.Logger.SetOutput(output)
}
}()
var err error
var wg = &sync.WaitGroup{}
events := subscription.Events()
ctx := context.Background()
syftUIHandler := ui.NewHandler()
eventLoop:
for {
select {
case err := <-workerErrs:
if err != nil {
return err
}
case e, ok := <-events:
if !ok {
break eventLoop
}
switch {
case syftUIHandler.RespondsTo(e):
if err = syftUIHandler.Handle(ctx, fr, e, wg); err != nil {
log.Errorf("unable to show %s event: %+v", e.Type, err)
}
case e.Type == syftEvent.AppUpdateAvailable:
if err = appUpdateAvailableHandler(ctx, fr, e, wg); err != nil {
log.Errorf("unable to show %s event: %+v", e.Type, err)
}
case e.Type == syftEvent.CatalogerFinished:
// we may have other background processes still displaying progress, wait for them to
// finish before discontinuing dynamic content and showing the final report
wg.Wait()
fr.Close()
// TODO: there is a race condition within frame.Close() that sometimes leads to an extra blank line being output
frame.Close()
isClosed = true
// flush any errors to the screen before the report
fmt.Fprint(output, logBuffer.String())
if err := common.CatalogerFinishedHandler(e); err != nil {
log.Errorf("unable to show %s event: %+v", e.Type, err)
}
// this is the last expected event
break eventLoop
}
case <-ctx.Done():
if ctx.Err() != nil {
log.Errorf("cancelled (%+v)", err)
}
break eventLoop
}
}
return nil
}