Refactor Tagger package. Add fsNotify Service

cmd/cc-backend/main.go

@@ -19,7 +19,9 @@ import (
 	"github.com/ClusterCockpit/cc-backend/internal/importer"
 	"github.com/ClusterCockpit/cc-backend/internal/metricdata"
 	"github.com/ClusterCockpit/cc-backend/internal/repository"
+	"github.com/ClusterCockpit/cc-backend/internal/tagger"
 	"github.com/ClusterCockpit/cc-backend/internal/taskManager"
+	"github.com/ClusterCockpit/cc-backend/internal/util"
 	"github.com/ClusterCockpit/cc-backend/pkg/archive"
 	"github.com/ClusterCockpit/cc-backend/pkg/log"
 	"github.com/ClusterCockpit/cc-backend/pkg/runtimeEnv"
@@ -216,6 +218,7 @@ func main() {
 	}
 
 	archiver.Start(repository.GetJobRepository())
+	tagger.Init()
 	taskManager.Start()
 	serverInit()
 
@@ -237,6 +240,8 @@ func main() {
 
 		serverShutdown()
 
+		util.FsWatcherShutdown()
+
 		taskManager.Shutdown()
 	}()
 

go.mod

@@ -44,6 +44,7 @@ require (
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.6 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/go-asn1-ber/asn1-ber v1.5.7 // indirect
 	github.com/go-jose/go-jose/v4 v4.0.5 // indirect
 	github.com/go-openapi/jsonpointer v0.21.0 // indirect

go.sum

@@ -55,6 +55,8 @@ github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4
 github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
 github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
+github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
 github.com/go-asn1-ber/asn1-ber v1.5.7 h1:DTX+lbVTWaTw1hQ+PbZPlnDZPEIs0SS/GCZAl535dDk=
 github.com/go-asn1-ber/asn1-ber v1.5.7/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
 github.com/go-co-op/gocron/v2 v2.16.0 h1:uqUF6WFZ4enRU45pWFNcn1xpDLc+jBOTKhPQI16Z1xs=

internal/repository/job.go

@@ -58,8 +58,10 @@ func GetJobRepository() *JobRepository {
 // }
 
 var jobColumns []string = []string{
-	"id", "job_id", "hpc_user", "project", "cluster", "subcluster", "start_time", "cluster_partition", "array_job_id", "num_nodes", "num_hwthreads", "num_acc", "exclusive", "monitoring_status", "smt", "job_state",
-	"duration", "walltime", "resources", "footprint", "energy",
+	"id", "job_id", "hpc_user", "project", "cluster", "subcluster", "start_time",
+	"cluster_partition", "array_job_id", "num_nodes", "num_hwthreads", "num_acc",
+	"exclusive", "monitoring_status", "smt", "job_state", "duration", "walltime",
+	"resources", "footprint", "energy",
 }
 
 func scanJob(row interface{ Scan(...any) error }) (*schema.Job, error) {

internal/tagger/detectApp.go

@@ -9,15 +9,20 @@ import (
 	"embed"
 	"fmt"
 	"io/fs"
+	"os"
 	"path/filepath"
 	"strings"
 
 	"github.com/ClusterCockpit/cc-backend/internal/repository"
+	"github.com/ClusterCockpit/cc-backend/internal/util"
 	"github.com/ClusterCockpit/cc-backend/pkg/log"
 	"github.com/ClusterCockpit/cc-backend/pkg/schema"
 )
 
-const tagType = "app"
+const (
+	tagType = "app"
+	appPath = "./var/tagger/apps"
+)
 
 //go:embed apps/*
 var appFiles embed.FS
@@ -31,14 +36,7 @@ type AppTagger struct {
 	apps map[string]appInfo
 }
 
-func (t *AppTagger) scanApps(files []fs.DirEntry) error {
-	for _, fn := range files {
-		fns := fn.Name()
-		log.Debugf("Process: %s", fns)
-		f, err := appFiles.Open(fmt.Sprintf("apps/%s", fns))
-		if err != nil {
-			return fmt.Errorf("error opening app file %s: %#v", fns, err)
-		}
+func (t *AppTagger) scanApp(f fs.File, fns string) {
 	scanner := bufio.NewScanner(f)
 	ai := appInfo{tag: strings.TrimSuffix(fns, filepath.Ext(fns)), strings: make([]string, 0)}
 
@@ -47,13 +45,28 @@ func (t *AppTagger) scanApps(files []fs.DirEntry) error {
 	}
 	delete(t.apps, ai.tag)
 	t.apps[ai.tag] = ai
-	}
-	return nil
 }
 
-// func (t *AppTagger) Reload() error {
-//
-// }
+func (t *AppTagger) EventMatch(s string) bool {
+	return strings.Contains(s, "apps")
+}
+
+func (t *AppTagger) EventCallback() {
+	files, err := os.ReadDir(appPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for _, fn := range files {
+		fns := fn.Name()
+		log.Debugf("Process: %s", fns)
+		f, err := os.Open(fmt.Sprintf("%s/%s", appPath, fns))
+		if err != nil {
+			log.Errorf("error opening app file %s: %#v", fns, err)
+		}
+		t.scanApp(f, fns)
+	}
+}
 
 func (t *AppTagger) Register() error {
 	files, err := appFiles.ReadDir("apps")
@@ -61,7 +74,22 @@ func (t *AppTagger) Register() error {
 		return fmt.Errorf("error reading app folder: %#v", err)
 	}
 	t.apps = make(map[string]appInfo, 0)
-	return t.scanApps(files)
+	for _, fn := range files {
+		fns := fn.Name()
+		log.Debugf("Process: %s", fns)
+		f, err := appFiles.Open(fmt.Sprintf("apps/%s", fns))
+		if err != nil {
+			return fmt.Errorf("error opening app file %s: %#v", fns, err)
+		}
+		t.scanApp(f, fns)
+	}
+
+	if util.CheckFileExists(appPath) {
+		log.Infof("Setup file watch for %s", appPath)
+		util.AddListener(appPath, t)
+	}
+
+	return nil
 }
 
 func (t *AppTagger) Match(job *schema.Job) {

internal/tagger/tagger.go

@@ -36,7 +36,6 @@ func Init() {
 			tagger.Register()
 		}
 
-		// jobTagger.stopTaggers = make([]Tagger, 0)
 		repository.RegisterJobJook(jobTagger)
 	})
 }

internal/util/fswatcher.go

@@ -0,0 +1,73 @@
+// Copyright (C) 2023 NHR@FAU, University Erlangen-Nuremberg.
+// All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+package util
+
+import (
+	"sync"
+
+	"github.com/ClusterCockpit/cc-backend/pkg/log"
+	"github.com/fsnotify/fsnotify"
+)
+
+type Listener interface {
+	EventCallback()
+	EventMatch(event string) bool
+}
+
+var (
+	initOnce  sync.Once
+	w         *fsnotify.Watcher
+	listeners []Listener
+)
+
+func AddListener(path string, l Listener) {
+	var err error
+
+	initOnce.Do(func() {
+		var err error
+		w, err = fsnotify.NewWatcher()
+		if err != nil {
+			log.Error("creating a new watcher: %w", err)
+		}
+		listeners = make([]Listener, 0)
+
+		go watchLoop(w)
+	})
+
+	listeners = append(listeners, l)
+	err = w.Add(path)
+	if err != nil {
+		log.Warnf("%q: %s", path, err)
+	}
+}
+
+func FsWatcherShutdown() {
+	w.Close()
+}
+
+func watchLoop(w *fsnotify.Watcher) {
+	for {
+		select {
+		// Read from Errors.
+		case err, ok := <-w.Errors:
+			if !ok { // Channel was closed (i.e. Watcher.Close() was called).
+				return
+			}
+			log.Errorf("watch event loop: %s", err)
+		// Read from Events.
+		case e, ok := <-w.Events:
+			if !ok { // Channel was closed (i.e. Watcher.Close() was called).
+				return
+			}
+
+			log.Infof("Event %s", e)
+			for _, l := range listeners {
+				if l.EventMatch(e.String()) {
+					l.EventCallback()
+				}
+			}
+		}
+	}
+}