[Refactor]: Core/API Split (#1506)

Refactors api folder to core, creates firm split between backend code and api frontend.

core/services/backend_monitor.go

@@ -0,0 +1,138 @@
+package services
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/go-skynet/LocalAI/pkg/grpc/proto"
+	"github.com/go-skynet/LocalAI/pkg/model"
+	"github.com/go-skynet/LocalAI/pkg/schema"
+	"github.com/rs/zerolog/log"
+
+	gopsutil "github.com/shirou/gopsutil/v3/process"
+)
+
+type BackendMonitor struct {
+	configLoader *ConfigLoader
+	modelLoader  *model.ModelLoader
+	options      *schema.StartupOptions // Taking options in case we need to inspect ExternalGRPCBackends, though that's out of scope for now, hence the name.
+}
+
+func NewBackendMonitor(configLoader *ConfigLoader, modelLoader *model.ModelLoader, options *schema.StartupOptions) *BackendMonitor {
+	return &BackendMonitor{
+		configLoader: configLoader,
+		modelLoader:  modelLoader,
+		options:      options,
+	}
+}
+
+func (bm *BackendMonitor) SampleLocalBackendProcess(model string) (*schema.BackendMonitorResponse, error) {
+	config, exists := bm.configLoader.GetConfig(model)
+	var backend string
+	if exists {
+		backend = config.Model
+	} else {
+		// Last ditch effort: use it raw, see if a backend happens to match.
+		backend = model
+	}
+
+	if !strings.HasSuffix(backend, ".bin") {
+		backend = fmt.Sprintf("%s.bin", backend)
+	}
+
+	pid, err := bm.modelLoader.GetGRPCPID(backend)
+
+	if err != nil {
+		log.Error().Msgf("model %s : failed to find pid %+v", model, err)
+		return nil, err
+	}
+
+	// Name is slightly frightening but this does _not_ create a new process, rather it looks up an existing process by PID.
+	backendProcess, err := gopsutil.NewProcess(int32(pid))
+
+	if err != nil {
+		log.Error().Msgf("model %s [PID %d] : error getting process info %+v", model, pid, err)
+		return nil, err
+	}
+
+	memInfo, err := backendProcess.MemoryInfo()
+
+	if err != nil {
+		log.Error().Msgf("model %s [PID %d] : error getting memory info %+v", model, pid, err)
+		return nil, err
+	}
+
+	memPercent, err := backendProcess.MemoryPercent()
+	if err != nil {
+		log.Error().Msgf("model %s [PID %d] : error getting memory percent %+v", model, pid, err)
+		return nil, err
+	}
+
+	cpuPercent, err := backendProcess.CPUPercent()
+	if err != nil {
+		log.Error().Msgf("model %s [PID %d] : error getting cpu percent %+v", model, pid, err)
+		return nil, err
+	}
+
+	return &schema.BackendMonitorResponse{
+		MemoryInfo:    memInfo,
+		MemoryPercent: memPercent,
+		CPUPercent:    cpuPercent,
+	}, nil
+}
+
+func (bm BackendMonitor) getModelLoaderIDFromModelName(modelName string) (string, error) {
+	config, exists := bm.configLoader.GetConfig(modelName)
+	var backendId string
+	if exists {
+		backendId = config.Model
+	} else {
+		// Last ditch effort: use it raw, see if a backend happens to match.
+		backendId = modelName
+	}
+
+	if !strings.HasSuffix(backendId, ".bin") {
+		backendId = fmt.Sprintf("%s.bin", backendId)
+	}
+
+	return backendId, nil
+}
+
+func (bm BackendMonitor) CheckAndSample(modelName string) (*proto.StatusResponse, error) {
+	backendId, err := bm.getModelLoaderIDFromModelName(modelName)
+	if err != nil {
+		return nil, err
+	}
+	modelAddr := bm.modelLoader.CheckIsLoaded(backendId)
+	if modelAddr == "" {
+		return nil, fmt.Errorf("backend %s is not currently loaded", backendId)
+	}
+
+	status, rpcErr := modelAddr.GRPC(false, nil).Status(context.TODO())
+	if rpcErr != nil {
+		log.Warn().Msgf("backend %s experienced an error retrieving status info: %s", backendId, rpcErr.Error())
+		val, slbErr := bm.SampleLocalBackendProcess(backendId)
+		if slbErr != nil {
+			return nil, fmt.Errorf("backend %s experienced an error retrieving status info via rpc: %s, then failed local node process sample: %s", backendId, rpcErr.Error(), slbErr.Error())
+		}
+		return &proto.StatusResponse{
+			State: proto.StatusResponse_ERROR,
+			Memory: &proto.MemoryUsageData{
+				Total: val.MemoryInfo.VMS,
+				Breakdown: map[string]uint64{
+					"gopsutil-RSS": val.MemoryInfo.RSS,
+				},
+			},
+		}, nil
+	}
+	return status, nil
+}
+
+func (bm BackendMonitor) ShutdownModel(modelName string) error {
+	backendId, err := bm.getModelLoaderIDFromModelName(modelName)
+	if err != nil {
+		return err
+	}
+	return bm.modelLoader.ShutdownModel(backendId)
+}