[WIP] File watch

Gopkg.toml

@@ -53,3 +53,7 @@
 [[constraint]]
   name = "github.com/alexellis/go-execute"
   version = "0.3.0"
+
+[[constraint]]
+  name = "github.com/fsnotify/fsnotify"
+  version = "1.4.7"

commands/up.go

@@ -5,21 +5,37 @@ package commands
 
 import (
 	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
 
+	"github.com/bep/debounce"
+	"github.com/fsnotify/fsnotify"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 )
 
 var (
-	skipPush   bool
-	skipDeploy bool
+	skipPush               bool
+	skipDeploy             bool
+	watch                  bool
+	ignoredDirs            []string
+	ignoredSuffixes        []string
+	ignoredDirsDefault     = []string{"build", ".git", "template"}
+	ignoredSuffixesDefault = []string{"~"}
 )
 
 func init() {
 
 	upFlagset := pflag.NewFlagSet("up", pflag.ExitOnError)
 	upFlagset.BoolVar(&skipPush, "skip-push", false, "Skip pushing function to remote registry")
 	upFlagset.BoolVar(&skipDeploy, "skip-deploy", false, "Skip function deployment")
+	upFlagset.BoolVar(&watch, "watch", false, "Watch for file changes and trigger up")
+	upFlagset.StringSliceVar(&ignoredDirs, "ignore-dir", []string{}, "Exclude directories from filesystem watch")
+	upFlagset.StringSliceVar(&ignoredSuffixes, "ignore-suffix", []string{}, "Exclude files with matching suffix from filesystem watch")
+
 	upCmd.Flags().AddFlagSet(upFlagset)
 
 	build, _, _ := faasCmd.Find([]string{"build"})
@@ -64,6 +80,88 @@ func preRunUp(cmd *cobra.Command, args []string) error {
 }
 
 func upHandler(cmd *cobra.Command, args []string) error {
+
+	if !watch {
+		return doUp(cmd, args)
+	}
+
+	ignoredDirs = append(ignoredDirs, ignoredDirsDefault...)
+	ignoredSuffixes = append(ignoredSuffixes, ignoredSuffixesDefault...)
+	ignoredSuffixes = append(ignoredSuffixes, ignoredDirs...)
+
+	debounced := debounce.New(500 * time.Millisecond)
+
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer watcher.Close()
+
+	done := make(chan bool)
+	go func() {
+		for {
+			select {
+			case event := <-watcher.Events:
+
+				log.Printf("changed: %s", event)
+
+				if skipIgnoredSuffix(event, ignoredSuffixes) {
+					break
+				}
+
+				if opWrite(event) {
+					debounced(func() {
+						if err := doUp(cmd, args); err != nil {
+							log.Printf("Error detecting change: %v", err)
+						}
+					})
+				}
+
+			case err := <-watcher.Errors:
+				fmt.Println("error:", err)
+			}
+		}
+	}()
+
+	cwd, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+	log.Println("Watching: ", cwd)
+
+	watchedDirs := []string{}
+	err = filepath.Walk(cwd,
+		func(path string, info os.FileInfo, err error) error {
+			if err != nil {
+				return err
+			}
+
+			if skipIgnoredDir(info, ignoredDirs) {
+				return filepath.SkipDir
+			}
+
+			if info.IsDir() {
+				if err = watcher.Add(path); err != nil {
+					return err
+				}
+				watchedDirs = append(watchedDirs, path)
+			}
+			return nil
+		})
+	if err != nil {
+		return err
+	}
+
+	<-done
+
+	return nil
+}
+
+func opWrite(event fsnotify.Event) bool {
+	return event.Op&fsnotify.Write == fsnotify.Write
+}
+
+func doUp(cmd *cobra.Command, args []string) error {
 	if err := runBuild(cmd, args); err != nil {
 		return err
 	}
@@ -81,3 +179,24 @@ func upHandler(cmd *cobra.Command, args []string) error {
 	}
 	return nil
 }
+
+func skipIgnoredDir(info os.FileInfo, ignoredDirs []string) bool {
+	if !info.IsDir() {
+		return false
+	}
+	for _, ignoredDir := range ignoredDirs {
+		if info.Name() == ignoredDir {
+			return true
+		}
+	}
+	return false
+}
+
+func skipIgnoredSuffix(event fsnotify.Event, ignoredSuffixes []string) bool {
+	for _, ignoredSuffix := range ignoredSuffixes {
+		if strings.HasSuffix(event.Name, ignoredSuffix) {
+			return true
+		}
+	}
+	return false
+}