using idleshut as a separate package

client.go

@@ -6,11 +6,11 @@ import (
 	"io/ioutil"
 	"net/http"
 	"os"
-	"os/exec"
 	"path"
-	"time"
+	"sync"
 
 	"git.stephensearles.com/stephen/acedoc"
+	"git.stephensearles.com/stephen/idleshut"
 )
 
 type editSession struct {
@@ -19,6 +19,14 @@ type editSession struct {
 	filename string
 	doc      *acedoc.Document
 	tmpdir   string
+	mtx      sync.Mutex
+}
+
+func (es *editSession) Clients() uint {
+	es.mtx.Lock()
+	defer es.mtx.Unlock()
+
+	return es.clients
 }
 
 func (ch *CaddyHugo) newEditSession(docName string) (*editSession, error) {
@@ -54,68 +62,15 @@ func (ch *CaddyHugo) newEditSession(docName string) (*editSession, error) {
 }
 
 func (ch *CaddyHugo) renderDraft(es *editSession) error {
-	hugoCmd := exec.Command("hugo", "--watch", "-D", "-d", es.tmpdir)
-	hugoCmd.Dir = ch.Dir
-	err := hugoCmd.Start()
-	if err != nil {
-		return fmt.Errorf("error starting hugo: %v", err)
-	}
+	var proc *idleshut.Process
 
-	renderer := HugoCmdRenderer{
-		TmpDir:   es.tmpdir,
-		SrcDir:   ch.Dir,
-		Filename: es.filename,
+	f := func() {
+		if es.clients != 0 {
+			proc.Touch()
+		}
 	}
 
-	go func() {
-		ticker := time.NewTicker(WebsocketFileTicker)
-		idleTicks := 0
-		closeTicks := int(IdleWebsocketTimeout / WebsocketFileTicker)
-
-		defer func() {
-			err = renderer.Stop()
-			if err != nil {
-				fmt.Println("error stopping hugo:", err)
-			}
-		}()
-
-		for {
-			<-ticker.C
-			ch.mtx.Lock()
-
-			// render if there are connected clients OR if we haven't
-			// been idle for very long.
-			if es.clients > 0 || idleTicks < 2 {
-				err := renderer.Render(es.doc.Contents())
-				if err != nil {
-					fmt.Println("error saving document contents:", err)
-				}
-			}
-
-			// count up idle time and possibly close down
-			if es.clients == 0 {
-				idleTicks++
-
-				if idleTicks >= closeTicks {
-					idleTime := time.Duration(idleTicks) * WebsocketFileTicker
-					err := ch.Publish()
-					fmt.Printf("idle for %v, quitting\n", idleTime)
-					if err != nil {
-						fmt.Printf(", error publishing: %v\n", err)
-					}
-
-					es.doc.Close()
-					os.RemoveAll(es.tmpdir)
-					delete(ch.docs, es.filename)
-					ch.mtx.Unlock()
-					return
-				}
-			} else {
-				idleTicks = 0
-			}
-			ch.mtx.Unlock()
-		}
-	}()
+	proc = idleshut.New(HugoCmdProcessConfig(ch, es, f))
 
 	return nil
 }

hugo.go

@@ -5,7 +5,8 @@ import (
 	"io/ioutil"
 	"os"
 	"os/exec"
-	"sync"
+
+	"git.stephensearles.com/stephen/idleshut"
 )
 
 type HugoInteractor interface {
@@ -13,55 +14,56 @@ type HugoInteractor interface {
 }
 
 type HugoRenderer interface {
+	WriteContent(contents string) error
 	Start() error
 	Stop() error
 }
 
-type HugoCmdRenderer struct {
-	SrcDir   string
-	TmpDir   string
-	Filename string
-
-	cmd *exec.Cmd
-	mtx sync.Mutex
-}
+func HugoCmdProcessConfig(ch *CaddyHugo, es *editSession, touchFn func()) idleshut.Config {
+	cmd := exec.Command("hugo", "--watch", "-D", "-d", es.tmpdir)
+	cmd.Dir = es.tmpdir
 
-func (hcr *HugoCmdRenderer) Render(contents string) error {
-	err := ioutil.WriteFile(hcr.Filename, []byte(contents), 0644)
-	return err
-}
+	return idleshut.Config{
+		Tick:         WebsocketFileTicker,
+		MaxIdleTicks: uint(IdleWebsocketTimeout/WebsocketFileTicker) + 1,
+		Start: func() error {
 
-func (hcr *HugoCmdRenderer) Start() error {
-	hcr.mtx.Lock()
-	defer hcr.mtx.Unlock()
+			err := cmd.Start()
+			if err != nil {
+				return fmt.Errorf("error starting hugo: %v", err)
+			}
 
-	hcr.cmd = exec.Command("hugo", "--watch", "-D", "-d", hcr.TmpDir)
-	hcr.cmd.Dir = hcr.TmpDir
+			return nil
+		},
+		Stop: func() error {
+			if cmd == nil {
+				return nil
+			}
 
-	err := hcr.cmd.Start()
-	if err != nil {
-		return fmt.Errorf("error starting hugo: %v", err)
-	}
+			err := cmd.Process.Signal(os.Interrupt)
+			if err != nil {
+				return fmt.Errorf("error signalling hugo to stop: %v", err)
+			}
+			err = cmd.Wait()
+			if err != nil {
+				return fmt.Errorf("error waiting for hugo to stop: %v", err)
+				return err
+			}
 
-	return nil
-}
+			es.doc.Close()
+			os.RemoveAll(es.tmpdir)
+			delete(ch.docs, es.filename)
 
-func (hcr *HugoCmdRenderer) Stop() error {
-	hcr.mtx.Lock()
-	defer hcr.mtx.Unlock()
-
-	if hcr.cmd == nil {
-		return nil
-	}
-
-	err := hcr.cmd.Process.Signal(os.Interrupt)
-	if err != nil {
-		return err
+			return nil
+		},
+		IdleProcessError: func(err error) {
+			fmt.Println("error processing draft:", err)
+		},
+		IdleTick: func() error {
+			return ioutil.WriteFile(es.filename, []byte(es.doc.Contents()), 0644)
+		},
+		ActiveTick: func() error {
+			return ioutil.WriteFile(es.filename, []byte(es.doc.Contents()), 0644)
+		},
 	}
-	err = hcr.cmd.Wait()
-	if err != nil {
-		return err
-	}
-
-	return nil
 }