chore(refactor): drop duplicated shutdown logics (#3589)

* chore(refactor): drop duplicated shutdown logics

- Handle locking in Shutdown and CheckModelIsLoaded in a more go-idiomatic way
- Drop duplicated code and re-organize shutdown code

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

* fix: drop leftover

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

* chore: improve logging and add missing locks

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

---------

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

core/http/routes/localai.go

@@ -69,6 +69,6 @@ func RegisterLocalAIRoutes(app *fiber.App,
 		}{Version: internal.PrintableVersion()})
 	})
 
-	app.Get("/system", auth, localai.SystemInformations(ml, appConfig))
+	app.Get("/system", localai.SystemInformations(ml, appConfig))
 
 }

pkg/model/filters.go

@@ -0,0 +1,17 @@
+package model
+
+import (
+	process "github.com/mudler/go-processmanager"
+)
+
+type GRPCProcessFilter = func(id string, p *process.Process) bool
+
+func all(_ string, _ *process.Process) bool {
+	return true
+}
+
+func allExcept(s string) GRPCProcessFilter {
+	return func(id string, p *process.Process) bool {
+		return id != s
+	}
+}

pkg/model/initializers.go

@@ -320,7 +320,7 @@ func (ml *ModelLoader) grpcModel(backend string, o *Options) func(string, string
 		} else {
 			grpcProcess := backendPath(o.assetDir, backend)
 			if err := utils.VerifyPath(grpcProcess, o.assetDir); err != nil {
-				return nil, fmt.Errorf("grpc process not found in assetdir: %s", err.Error())
+				return nil, fmt.Errorf("refering to a backend not in asset dir: %s", err.Error())
 			}
 
 			if autoDetect {
@@ -332,7 +332,7 @@ func (ml *ModelLoader) grpcModel(backend string, o *Options) func(string, string
 
 			// Check if the file exists
 			if _, err := os.Stat(grpcProcess); os.IsNotExist(err) {
-				return nil, fmt.Errorf("grpc process not found: %s. some backends(stablediffusion, tts) require LocalAI compiled with GO_TAGS", grpcProcess)
+				return nil, fmt.Errorf("backend not found: %s", grpcProcess)
 			}
 
 			serverAddress, err := getFreeAddress()
@@ -355,6 +355,8 @@ func (ml *ModelLoader) grpcModel(backend string, o *Options) func(string, string
 			client = NewModel(serverAddress)
 		}
 
+		log.Debug().Msgf("Wait for the service to start up")
+
 		// Wait for the service to start up
 		ready := false
 		for i := 0; i < o.grpcAttempts; i++ {
@@ -413,10 +415,8 @@ func (ml *ModelLoader) BackendLoader(opts ...Option) (client grpc.Backend, err e
 	}
 
 	if o.singleActiveBackend {
-		ml.mu.Lock()
 		log.Debug().Msgf("Stopping all backends except '%s'", o.model)
-		err := ml.StopAllExcept(o.model)
-		ml.mu.Unlock()
+		err := ml.StopGRPC(allExcept(o.model))
 		if err != nil {
 			log.Error().Err(err).Str("keptModel", o.model).Msg("error while shutting down all backends except for the keptModel")
 			return nil, err
@@ -444,13 +444,10 @@ func (ml *ModelLoader) BackendLoader(opts ...Option) (client grpc.Backend, err e
 func (ml *ModelLoader) GreedyLoader(opts ...Option) (grpc.Backend, error) {
 	o := NewOptions(opts...)
 
-	ml.mu.Lock()
-
 	// Return earlier if we have a model already loaded
 	// (avoid looping through all the backends)
 	if m := ml.CheckIsLoaded(o.model); m != nil {
 		log.Debug().Msgf("Model '%s' already loaded", o.model)
-		ml.mu.Unlock()
 
 		return m.GRPC(o.parallelRequests, ml.wd), nil
 	}
@@ -458,12 +455,11 @@ func (ml *ModelLoader) GreedyLoader(opts ...Option) (grpc.Backend, error) {
 	// If we can have only one backend active, kill all the others (except external backends)
 	if o.singleActiveBackend {
 		log.Debug().Msgf("Stopping all backends except '%s'", o.model)
-		err := ml.StopAllExcept(o.model)
+		err := ml.StopGRPC(allExcept(o.model))
 		if err != nil {
 			log.Error().Err(err).Str("keptModel", o.model).Msg("error while shutting down all backends except for the keptModel - greedyloader continuing")
 		}
 	}
-	ml.mu.Unlock()
 
 	var err error
 

pkg/model/loader.go

@@ -118,9 +118,6 @@ func (ml *ModelLoader) ListModels() []*Model {
 }
 
 func (ml *ModelLoader) LoadModel(modelName string, loader func(string, string) (*Model, error)) (*Model, error) {
-	ml.mu.Lock()
-	defer ml.mu.Unlock()
-
 	// Check if we already have a loaded model
 	if model := ml.CheckIsLoaded(modelName); model != nil {
 		return model, nil
@@ -139,6 +136,8 @@ func (ml *ModelLoader) LoadModel(modelName string, loader func(string, string) (
 		return nil, fmt.Errorf("loader didn't return a model")
 	}
 
+	ml.mu.Lock()
+	defer ml.mu.Unlock()
 	ml.models[modelName] = model
 
 	return model, nil
@@ -168,6 +167,8 @@ func (ml *ModelLoader) ShutdownModel(modelName string) error {
 }
 
 func (ml *ModelLoader) CheckIsLoaded(s string) *Model {
+	ml.mu.Lock()
+	defer ml.mu.Unlock()
 	m, ok := ml.models[s]
 	if !ok {
 		return nil

pkg/model/process.go

@@ -9,28 +9,12 @@ import (
 	"strconv"
 	"strings"
 	"syscall"
-	"time"
 
 	"github.com/hpcloud/tail"
 	process "github.com/mudler/go-processmanager"
 	"github.com/rs/zerolog/log"
 )
 
-func (ml *ModelLoader) StopAllExcept(s string) error {
-	return ml.StopGRPC(func(id string, p *process.Process) bool {
-		if id == s {
-			return false
-		}
-
-		for ml.models[id].GRPC(false, ml.wd).IsBusy() {
-			log.Debug().Msgf("%s busy. Waiting.", id)
-			time.Sleep(2 * time.Second)
-		}
-		log.Debug().Msgf("[single-backend] Stopping %s", id)
-		return true
-	})
-}
-
 func (ml *ModelLoader) deleteProcess(s string) error {
 	if _, exists := ml.grpcProcesses[s]; exists {
 		if err := ml.grpcProcesses[s].Stop(); err != nil {
@@ -42,17 +26,11 @@ func (ml *ModelLoader) deleteProcess(s string) error {
 	return nil
 }
 
-type GRPCProcessFilter = func(id string, p *process.Process) bool
-
-func includeAllProcesses(_ string, _ *process.Process) bool {
-	return true
-}
-
 func (ml *ModelLoader) StopGRPC(filter GRPCProcessFilter) error {
 	var err error = nil
 	for k, p := range ml.grpcProcesses {
 		if filter(k, p) {
-			e := ml.deleteProcess(k)
+			e := ml.ShutdownModel(k)
 			err = errors.Join(err, e)
 		}
 	}
@@ -60,10 +38,12 @@ func (ml *ModelLoader) StopGRPC(filter GRPCProcessFilter) error {
 }
 
 func (ml *ModelLoader) StopAllGRPC() error {
-	return ml.StopGRPC(includeAllProcesses)
+	return ml.StopGRPC(all)
 }
 
 func (ml *ModelLoader) GetGRPCPID(id string) (int, error) {
+	ml.mu.Lock()
+	defer ml.mu.Unlock()
 	p, exists := ml.grpcProcesses[id]
 	if !exists {
 		return -1, fmt.Errorf("no grpc backend found for %s", id)