feat: dutagent runs module init on startup

Signed-off-by: Jens Drenhaus <jens.drenhaus@blindspot.software>

cmds/dutagent/dutagent.go

@@ -5,11 +5,13 @@ package main
 
 import (
 	"context"
+	"errors"
 	"log"
 	"net/http"
 	"os"
 
 	"connectrpc.com/connect"
+	"github.com/BlindspotSoftware/dutctl/internal/dutagent"
 	"github.com/BlindspotSoftware/dutctl/protobuf/gen/dutctl/v1/dutctlv1connect"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/h2c"
@@ -75,6 +77,16 @@ func main() {
 		log.Fatal(err)
 	}
 
+	if err = dutagent.Init(cfg.Devices); err != nil {
+		var initerr *dutagent.ModuleInitError
+		if errors.As(err, &initerr) {
+			for mod, err := range initerr.Errs {
+				log.Printf("init %s failed with:\n%v\n", mod, err)
+			}
+		}
+		log.Fatal(err)
+	}
+
 	agent := &dutagentService{
 		devices: cfg.Devices,
 	}

internal/dutagent/init.go

@@ -0,0 +1,47 @@
+package dutagent
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/BlindspotSoftware/dutctl/pkg/dut"
+)
+
+// ModuleInitError is a container for errors that occur during module
+// initialization.
+type ModuleInitError struct {
+	Errs map[string]error
+}
+
+func (e *ModuleInitError) Error() string {
+	return fmt.Sprintf("\n%d initialization errors", len(e.Errs))
+}
+
+// Init runs the Init function of all modules for all commands of the provided
+// devices. All init functions are called, even if an error occurs. In this case
+// the an ModuleInitErr is returned that holds all errors reported by the modules.
+func Init(devices dut.Devlist) error {
+	var ierr = &ModuleInitError{
+		Errs: map[string]error{},
+	}
+
+	for devname, device := range devices {
+		for cmdname, cmd := range device.Cmds {
+			for _, module := range cmd.Modules {
+				err := module.Init()
+				if err != nil {
+					m := fmt.Sprintf("dev: %s, cmd: %s, mod: %s", devname, cmdname, module.Config.Name)
+					ierr.Errs[m] = err
+				}
+			}
+		}
+	}
+
+	if len(ierr.Errs) != 0 {
+		return ierr
+	}
+
+	log.Print("Module Initialization OK")
+
+	return nil
+}

pkg/module/module.go

@@ -24,10 +24,13 @@ type Module interface {
 	// Help returns a formatted string with the capabilities of the module.
 	// It provides any user information required to interact with the module.
 	Help() string
-	// Init is called when the module is loaded by dutagent on an execution request for a command that uses this module.
+	// Init is called once when the dutagent services is started.
+	// It's a good place to establish connections or allocate resources and check whether
+	// the module is configured functional
 	Init() error
-	// Deinit is called when the module is unloaded by dutagent after the execution of a command that uses this module.
-	// It is used to clean up any resources that were allocated during the Init phase.
+	// Deinit is called when the module is unloaded by dutagent or an internal error occurs.
+	// It is used to clean up any resources that were allocated during the Init phase and
+	// shall guarantee a graceful shutdown of the service
 	Deinit() error
 	// Run is the entry point and executes the module with the given arguments.
 	Run(ctx context.Context, s Session, args ...string) error