feat: Add a way to disable the indexer

This is only for archive support at the moment, and configuring a node
with the indexer disabled will also prevent it from writing to the db.

Author: Yawning

conf/config.go

@@ -22,7 +22,8 @@ type Config struct {
 	// blocks that the node doesn't have data for, such as by skipping them in checkpoint sync.
 	// For sensible reasons, indexing may actually start at an even later block, such as if
 	// this block is already indexed or the node indicates that it doesn't have this block.
-	IndexingStart uint64 `koanf:"indexing_start"`
+	IndexingStart   uint64 `koanf:"indexing_start"`
+	IndexingDisable bool   `koanf:"indexing_disable"`
 
 	Log      *LogConfig      `koanf:"log"`
 	Cache    *CacheConfig    `koanf:"cache"`

indexer/indexer.go

@@ -43,10 +43,11 @@ var ErrNotHealthy = errors.New("not healthy")
 type Service struct {
 	service.BaseBackgroundService
 
-	runtimeID     common.Namespace
-	enablePruning bool
-	pruningStep   uint64
-	indexingStart uint64
+	runtimeID       common.Namespace
+	enablePruning   bool
+	pruningStep     uint64
+	indexingStart   uint64
+	indexingDisable bool
 
 	backend Backend
 	client  client.RuntimeClient
@@ -303,6 +304,14 @@ func (s *Service) indexingWorker() {
 
 // Start starts service.
 func (s *Service) Start() {
+	// TODO/NotYawning: Non-archive nodes that have the indexer disabled
+	// likey want to use a different notion of healthy, and probably also
+	// want to start a worker that monitors the database for changes.
+	if s.indexingDisable {
+		s.updateHealth(true)
+		return
+	}
+
 	go s.indexingWorker()
 	go s.healthWorker()
 
@@ -339,8 +348,20 @@ func New(
 		enablePruning:         cfg.EnablePruning,
 		pruningStep:           cfg.PruningStep,
 		indexingStart:         cfg.IndexingStart,
+		indexingDisable:       cfg.IndexingDisable,
 	}
 	s.Logger = s.Logger.With("runtime_id", s.runtimeID.String())
 
+	// TODO/NotYawning: Non-archive nodes probably want to do something
+	// different here.
+	if s.indexingDisable {
+		if _, err := s.backend.QueryLastIndexedRound(ctx); err != nil {
+			s.Logger.Error("indexer disabled and no rounds indexed, this will never work",
+				"err", err,
+			)
+			return nil, nil, err
+		}
+	}
+
 	return s, cachingBackend, nil
 }

main.go

@@ -114,7 +114,7 @@ func truncateExec(cmd *cobra.Command, args []string) error {
 	}
 
 	// Initialize db.
-	db, err := psql.InitDB(ctx, cfg.Database, true)
+	db, err := psql.InitDB(ctx, cfg.Database, true, false)
 	if err != nil {
 		logger.Error("failed to initialize db", "err", err)
 		return err
@@ -145,7 +145,7 @@ func migrateExec(cmd *cobra.Command, args []string) error {
 	logger := logging.GetLogger("migrate-db")
 
 	// Initialize db.
-	db, err := psql.InitDB(ctx, cfg.Database, true)
+	db, err := psql.InitDB(ctx, cfg.Database, true, false)
 	if err != nil {
 		logger.Error("failed to initialize db", "err", err)
 		return err
@@ -192,8 +192,13 @@ func runRoot() error {
 	// Create the runtime client with account module query helpers.
 	rc := client.New(conn, runtimeID)
 
+	// For now, "disable" write access to the DB in a kind of kludgy way
+	// if the indexer is disabled.  Yes this means that no migrations
+	// can be done.  Deal with it.
+	dbReadOnly := cfg.IndexingDisable
+
 	// Initialize db for migrations (higher timeouts).
-	db, err := psql.InitDB(ctx, cfg.Database, true)
+	db, err := psql.InitDB(ctx, cfg.Database, true, dbReadOnly)
 	if err != nil {
 		logger.Error("failed to initialize db", "err", err)
 		return err
@@ -208,7 +213,7 @@ func runRoot() error {
 
 	// Initialize db again, now with configured timeouts.
 	var storage storage.Storage
-	storage, err = psql.InitDB(ctx, cfg.Database, false)
+	storage, err = psql.InitDB(ctx, cfg.Database, false, dbReadOnly)
 	if err != nil {
 		logger.Error("failed to initialize db", "err", err)
 		return err

storage/psql/psql.go

@@ -30,7 +30,12 @@ type PostDB struct {
 }
 
 // InitDB creates postgresql db instance.
-func InitDB(ctx context.Context, cfg *conf.DatabaseConfig, longTimeouts bool) (*PostDB, error) {
+func InitDB(
+	ctx context.Context,
+	cfg *conf.DatabaseConfig,
+	longTimeouts bool,
+	readOnly bool,
+) (*PostDB, error) {
 	if cfg == nil {
 		return nil, errors.New("nil configuration")
 	}
@@ -63,6 +68,19 @@ func InitDB(ctx context.Context, cfg *conf.DatabaseConfig, longTimeouts bool) (*
 		}
 	}
 
+	// Set "read-only" mode by setting the default status of new
+	// transactions.
+	//
+	// Note: This still allows txes to alter temporary tables, and is
+	// advisory rather than something that is securely enforced.
+	if readOnly {
+		opts = append(opts, pgdriver.WithConnParams(
+			map[string]interface{}{
+				"default_transaction_read_only": "on",
+			},
+		))
+	}
+
 	pgConn := pgdriver.NewConnector(opts...)
 	sqlDB := sql.OpenDB(pgConn)
 	maxOpenConns := cfg.MaxOpenConns

storage/psql/psql_test.go

@@ -21,7 +21,7 @@ func TestMain(m *testing.M) {
 	var err error
 	ctx := context.Background()
 	tests.MustInitConfig()
-	db, err = InitDB(ctx, tests.TestsConfig.Database, false)
+	db, err = InitDB(ctx, tests.TestsConfig.Database, false, false)
 	if err != nil {
 		log.Println(`It seems database failed to initialize. Do you have PostgreSQL running? If not, you can run
 docker run  -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=postgres -e POSTGRES_DB=postgres  -p 5432:5432 -d postgres`)

tests/rpc/utils.go

@@ -130,7 +130,7 @@ func Setup() error {
 
 	// Initialize db.
 	ctx := context.Background()
-	db, err = psql.InitDB(ctx, tests.TestsConfig.Database, true)
+	db, err = psql.InitDB(ctx, tests.TestsConfig.Database, true, false)
 	if err != nil {
 		return fmt.Errorf("failed to initialize DB: %w", err)
 	}
@@ -143,7 +143,7 @@ func Setup() error {
 
 	// Initialize db again, now with configured timeouts.
 	var storage storage.Storage
-	storage, err = psql.InitDB(ctx, tests.TestsConfig.Database, false)
+	storage, err = psql.InitDB(ctx, tests.TestsConfig.Database, false, false)
 	if err != nil {
 		return err
 	}