refactor: replace Service with its implementation

Currently, there isn't a need to have multiple implementations of the Service interface. Therefore, this commits replaces it with its only implementation to keep things simple.

internal/services/service.go

@@ -1,7 +1,8 @@
 // (c) Cartesi and individual authors (see AUTHORS)
 // SPDX-License-Identifier: Apache-2.0 (see LICENSE)
 
-// Package services provides mechanisms to start multiple services in the background
+// Package services provides mechanisms to start multiple services in the
+// background
 package services
 
 import (
@@ -17,33 +18,22 @@ import (
 	"github.com/cartesi/rollups-node/internal/logger"
 )
 
-// A service that runs in the background endlessly until the context is canceled
-type Service interface {
-	fmt.Stringer
-
-	// Start a service that will run until completion or until the context is
-	// canceled
-	Start(ctx context.Context) error
-
-	// Block until the service is ready or context is canceled
-	Ready(ctx context.Context) error
-}
-
 const (
 	DefaultServiceTimeout  = 15 * time.Second
 	DefaultDialInterval    = 100 * time.Millisecond
 	DefaultStateServerPort = "50051"
 	DefaultHealthcheckPort = "8080"
 )
 
-// simpleService implements the context cancelation logic of the Service interface
-type simpleService struct {
-	serviceName     string
+type Service struct {
+	name            string
 	binaryName      string
 	healthcheckPort string
 }
 
-func (s simpleService) Start(ctx context.Context) error {
+// Start will execute a binary and wait for its completion or until the context
+// is canceled
+func (s Service) Start(ctx context.Context) error {
 	cmd := exec.Command(s.binaryName)
 	cmd.Stderr = os.Stderr
 	cmd.Stdout = os.Stdout
@@ -57,7 +47,7 @@ func (s simpleService) Start(ctx context.Context) error {
 		logger.Debug.Printf("%v: %v\n", s.String(), ctx.Err())
 		if err := cmd.Process.Signal(syscall.SIGTERM); err != nil {
 			msg := "%v: failed to send SIGTERM to %v\n"
-			logger.Error.Printf(msg, s.String(), s.binaryName)
+			logger.Error.Printf(msg, s.String(), s.name)
 		}
 	}()
 
@@ -72,7 +62,7 @@ func (s simpleService) Start(ctx context.Context) error {
 //
 // A service is considered ready when it is possible to establish a connection
 // to its healthcheck endpoint.
-func (s simpleService) Ready(ctx context.Context) error {
+func (s Service) Ready(ctx context.Context) error {
 	for {
 		select {
 		case <-ctx.Done():
@@ -89,8 +79,8 @@ func (s simpleService) Ready(ctx context.Context) error {
 	}
 }
 
-func (s simpleService) String() string {
-	return s.serviceName
+func (s Service) String() string {
+	return s.name
 }
 
 // The Run function serves as a very simple supervisor: it will start all the
@@ -102,7 +92,7 @@ func Run(ctx context.Context, services []Service) {
 	}
 
 	// start services
-	startedServices := 0
+	startedServicesCount := 0
 	ctx, cancel := context.WithCancel(ctx)
 	exit := make(chan struct{}, len(services))
 	for _, service := range services {
@@ -138,7 +128,7 @@ func Run(ctx context.Context, services []Service) {
 	wait := make(chan struct{})
 	go func() {
 		cancel()
-		for i := 0; i < startedServices; i++ {
+		for i := 0; i < startedServicesCount; i++ {
 			<-exit
 		}
 		wait <- struct{}{}
@@ -184,33 +174,33 @@ func healthcheckEnv(serviceName string) string {
 }
 
 var (
-	AdvanceRunner = simpleService{
-		serviceName:     "advance-runner",
+	AdvanceRunner = Service{
+		name:            "advance-runner",
 		binaryName:      "cartesi-rollups-advance-runner",
 		healthcheckPort: healthcheckPort("advance-runner"),
 	}
-	Dispatcher = simpleService{
-		serviceName:     "dispatcher",
+	Dispatcher = Service{
+		name:            "dispatcher",
 		binaryName:      "cartesi-rollups-dispatcher",
 		healthcheckPort: healthcheckPort("dispatcher"),
 	}
-	GraphQLServer Service = simpleService{
-		serviceName:     "graphql-server",
+	GraphQLServer Service = Service{
+		name:            "graphql-server",
 		binaryName:      "cartesi-rollups-graphql-server",
 		healthcheckPort: healthcheckPort("graphql-server"),
 	}
-	Indexer Service = simpleService{
-		serviceName:     "indexer",
+	Indexer Service = Service{
+		name:            "indexer",
 		binaryName:      "cartesi-rollups-indexer",
 		healthcheckPort: healthcheckPort("indexer"),
 	}
-	InspectServer = simpleService{
-		serviceName:     "inspect-server",
+	InspectServer = Service{
+		name:            "inspect-server",
 		binaryName:      "cartesi-rollups-inspect-server",
 		healthcheckPort: healthcheckPort("inspect-server"),
 	}
-	StateServer = simpleService{
-		serviceName:     "state-server",
+	StateServer = Service{
+		name:            "state-server",
 		binaryName:      "cartesi-rollups-state-server",
 		healthcheckPort: healthcheckPort("state-server"),
 	}

internal/services/simple_service_test.go → internal/services/service_test.go

@@ -20,13 +20,13 @@ func setup() {
 	setRustBinariesPath()
 }
 
-func TestSimpleService(t *testing.T) {
+func TestService(t *testing.T) {
 
 	t.Run("it stops when the context is cancelled", func(t *testing.T) {
 		setup()
-		service := simpleService{
-			serviceName: "graphql-server",
-			binaryName:  "cartesi-rollups-graphql-server",
+		service := Service{
+			name:       "graphql-server",
+			binaryName: "cartesi-rollups-graphql-server",
 		}
 		ctx, cancel := context.WithCancel(context.Background())
 		exit := make(chan error)