Provide Running call to see if the service is "up enough" (#340)

* Provide Running call to see if the service is "up enough"

* Revert " fragile test case + race condition fixes (#337)"

This reverts commit c1243e7.

* only print an error if it fails on close

* Revert "Revert " fragile test case + race condition fixes (#337)""

This reverts commit 7e19d72.

* Be a lot more explicit when errors occur on New in database open

database/level/level.go

@@ -163,6 +163,9 @@ func New(ctx context.Context, home string, version int) (*Database, error) {
 	log.Tracef("New")
 	defer log.Tracef("New exit")
 
+	// Care must be taken to not shadow err and l in this function. The
+	// defer will overwrite those if an unwind condition occurs.
+
 	h, err := homedir.Expand(home)
 	if err != nil {
 		return nil, fmt.Errorf("home dir: %w", err)
@@ -181,7 +184,14 @@ func New(ctx context.Context, home string, version int) (*Database, error) {
 	unwind := true
 	defer func() {
 		if unwind {
-			log.Errorf("new unwind exited with: %v", l.Close())
+			cerr := l.Close()
+			if cerr != nil {
+				log.Debugf("new unwind exited with: %v", cerr)
+				err = errors.Join(err, cerr)
+			}
+			clear(l.pool)
+			clear(l.rawPool)
+			l = nil // Reset l
 		}
 	}()
 
@@ -240,7 +250,8 @@ func New(ctx context.Context, home string, version int) (*Database, error) {
 			dbVersion, version)
 	}
 
-	unwind = false
+	unwind = false // Everything is good, do not unwind.
 
-	return l, nil
+	// The defer above will set/reset these values.
+	return l, err
 }

go.mod

@@ -28,7 +28,6 @@ require (
 	github.com/sethvargo/go-retry v0.3.0
 	github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7
 	github.com/testcontainers/testcontainers-go v0.32.0
-	golang.org/x/sys v0.23.0
 )
 
 require (
@@ -90,6 +89,7 @@ require (
 	go.opentelemetry.io/otel/metric v1.24.0 // indirect
 	go.opentelemetry.io/otel/trace v1.24.0 // indirect
 	golang.org/x/crypto v0.22.0 // indirect
+	golang.org/x/sys v0.23.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20231016165738-49dd2c1f3d0b // indirect
 	google.golang.org/grpc v1.59.0 // indirect
 	google.golang.org/protobuf v1.34.2 // indirect

service/tbc/tbc.go

@@ -165,10 +165,6 @@ type Server struct {
 	// WebSockets
 	sessions       map[string]*tbcWs
 	requestTimeout time.Duration
-
-	// ignoreUlimit will explicitly not check ulimit settings on the host
-	// machine, this is useful for very small datasets/chains
-	ignoreUlimit bool
 }
 
 func NewServer(cfg *Config) (*Server, error) {
@@ -579,7 +575,7 @@ func (s *Server) handlePeer(ctx context.Context, p *rawpeer.RawPeer) error {
 	}
 }
 
-func (s *Server) running() bool {
+func (s *Server) Running() bool {
 	s.mtx.RLock()
 	defer s.mtx.RUnlock()
 	return s.isRunning
@@ -594,7 +590,7 @@ func (s *Server) testAndSetRunning(b bool) bool {
 }
 
 func (s *Server) promRunning() float64 {
-	r := s.running()
+	r := s.Running()
 	if r {
 		return 1
 	}
@@ -2228,28 +2224,9 @@ func (s *Server) Run(pctx context.Context) error {
 		return errors.New("run called but External Header mode is enabled")
 	}
 
-	if !s.testAndSetRunning(true) {
-		return errors.New("tbc already running")
-	}
-	defer s.testAndSetRunning(false)
-
-	// We need a lot of open files and memory for the indexes. Best effort
-	// to echo to the user what the ulimits are.
-	s.ignoreUlimit = true
-	if s.ignoreUlimit || s.cfg.Network == networkLocalnet {
-		log.Warningf("ignoring ulimit requirements")
-	} else if ulimitSupported {
-		if err := verifyUlimits(); err != nil {
-			return fmt.Errorf("verify ulimits: %w", err)
-		}
-	} else {
-		log.Errorf("This architecture does not supported ulimit verification. " +
-			"Consult the README for minimum values.")
-	}
-
+	// Rely on DBOpen failing if the database is already open.
 	ctx, cancel := context.WithCancel(pctx)
 	defer cancel()
-
 	err := s.DBOpen(ctx)
 	if err != nil {
 		return fmt.Errorf("open level database: %w", err)
@@ -2261,6 +2238,11 @@ func (s *Server) Run(pctx context.Context) error {
 		}
 	}()
 
+	if !s.testAndSetRunning(true) {
+		return errors.New("tbc already running")
+	}
+	defer s.testAndSetRunning(false)
+
 	// Find out where IBD is at
 	bhb, err := s.db.BlockHeaderBest(ctx)
 	if err != nil {

service/tbc/tbc_test.go

@@ -834,8 +834,6 @@ func createTbcServer(ctx context.Context, t *testing.T, mappedPeerPort nat.Port)
 		t.Fatal(err)
 	}
 
-	tbcServer.ignoreUlimit = true
-
 	go func() {
 		err := tbcServer.Run(ctx)
 		if err != nil && !errors.Is(err, context.Canceled) {
@@ -1064,7 +1062,6 @@ func createTbcServerExternalHeaderMode(ctx context.Context, t *testing.T) *Serve
 		t.Fatal(err)
 	}
 
-	tbcServer.ignoreUlimit = true
 	tbcServer.ExternalHeaderSetup(ctx, defaultUpstreamStateId[:])
 	return tbcServer
 }

service/tbc/tbcfork_test.go

@@ -911,7 +911,6 @@ func TestFork(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	s.ignoreUlimit = true
 	go func() {
 		log.Infof("s run")
 		defer log.Infof("s run done")
@@ -1149,7 +1148,6 @@ func TestIndexNoFork(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	s.ignoreUlimit = true
 
 	go func() {
 		err := s.Run(ctx)
@@ -1322,7 +1320,6 @@ func TestIndexFork(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	s.ignoreUlimit = true
 	go func() {
 		err := s.Run(ctx)
 		if err != nil && !errors.Is(err, context.Canceled) && !errors.Is(err, rawpeer.ErrNoConn) {