services/horizon: Allow customization of the Captive Core log file. (#…

…3472)

Introduces the --captive-core-log-path parameter.

Now, we can pass along to Stellar-Core's LOG_FILE_PATH="..." 
based on the value of the above parameter. We will still always 
log to Horizon's subservice=stellar-core.

Co-authored-by: Bartek Nowotarski <bartek@nowotarski.info>

ingest/ledgerbackend/captive_core_backend.go

@@ -124,6 +124,9 @@ type CaptiveCoreConfig struct {
 	// Log is an (optional) custom logger which will capture any output from the Stellar Core process.
 	// If Log is omitted then all output will be printed to stdout.
 	Log *log.Entry
+	// LogPath is the (optional) path in which to store Core logs, passed along
+	// to Stellar Core's LOG_FILE_PATH
+	LogPath string
 	// Context is the (optional) context which controls the lifetime of a CaptiveStellarCore instance. Once the context is done
 	// the CaptiveStellarCore instance will not be able to stream ledgers from Stellar Core or spawn new
 	// instances of Stellar Core. If Context is omitted CaptiveStellarCore will default to using context.Background.
@@ -134,11 +137,14 @@ type CaptiveCoreConfig struct {
 func NewCaptive(config CaptiveCoreConfig) (*CaptiveStellarCore, error) {
 	// Here we set defaults in the config. Because config is not a pointer this code should
 	// not mutate the original CaptiveCoreConfig instance which was passed into NewCaptive()
+
+	// Log Captive Core straight to stdout by default
 	if config.Log == nil {
 		config.Log = log.New()
 		config.Log.Logger.SetOutput(os.Stdout)
 		config.Log.SetLevel(logrus.InfoLevel)
 	}
+
 	parentCtx := config.Context
 	if parentCtx == nil {
 		parentCtx = context.Background()

ingest/ledgerbackend/stellar_core_runner.go

@@ -48,6 +48,7 @@ type pipe struct {
 }
 
 type stellarCoreRunner struct {
+	logPath           string
 	executablePath    string
 	configAppendPath  string
 	networkPassphrase string
@@ -82,6 +83,7 @@ func newStellarCoreRunner(config CaptiveCoreConfig, mode stellarCoreRunnerMode)
 	ctx, cancel := context.WithCancel(config.Context)
 
 	runner := &stellarCoreRunner{
+		logPath:           config.LogPath,
 		executablePath:    config.BinaryPath,
 		configAppendPath:  config.ConfigAppendPath,
 		networkPassphrase: config.NetworkPassphrase,
@@ -116,7 +118,7 @@ func (r *stellarCoreRunner) generateConfig() (string, error) {
 		fmt.Sprintf(`NETWORK_PASSPHRASE="%s"`, r.networkPassphrase),
 		fmt.Sprintf(`BUCKET_DIR_PATH="%s"`, filepath.Join(r.tempDir, "buckets")),
 		fmt.Sprintf(`HTTP_PORT=%d`, r.httpPort),
-		`LOG_FILE_PATH=""`,
+		fmt.Sprintf(`LOG_FILE_PATH="%s"`, r.logPath),
 	}
 
 	if r.mode == stellarCoreRunnerModeOffline {

services/horizon/internal/config.go

@@ -21,6 +21,7 @@ type Config struct {
 	CaptiveCoreConfigAppendPath string
 	RemoteCaptiveCoreURL        string
 	CaptiveCoreHTTPPort         uint
+	CaptiveCoreLogPath          string
 
 	StellarCoreDatabaseURL string
 	StellarCoreURL         string

services/horizon/internal/flags.go

@@ -255,6 +255,12 @@ func Flags() (*Config, support.ConfigOptions) {
 			OptType:   types.String,
 			Usage:     "name of the file where logs will be saved (leave empty to send logs to stdout)",
 		},
+		&support.ConfigOption{
+			Name:      "captive-core-log-path",
+			ConfigKey: &config.CaptiveCoreLogPath,
+			OptType:   types.String,
+			Usage:     "name of the path for Core logs (leave empty to log w/ Horizon only)",
+		},
 		&support.ConfigOption{
 			Name:        "max-path-length",
 			ConfigKey:   &config.MaxPathLength,

services/horizon/internal/ingest/main.go

@@ -71,6 +71,7 @@ type Config struct {
 	CaptiveCoreBinaryPath       string
 	CaptiveCoreConfigAppendPath string
 	CaptiveCoreHTTPPort         uint
+	CaptiveCoreLogPath          string
 	RemoteCaptiveCoreURL        string
 	NetworkPassphrase           string
 
@@ -189,16 +190,18 @@ func NewSystem(config Config) (System, error) {
 				return nil, errors.Wrap(err, "error creating captive core backend")
 			}
 		} else {
+			logger := log.WithField("subservice", "stellar-core")
 			ledgerBackend, err = ledgerbackend.NewCaptive(
 				ledgerbackend.CaptiveCoreConfig{
+					LogPath:             config.CaptiveCoreLogPath,
 					BinaryPath:          config.CaptiveCoreBinaryPath,
 					ConfigAppendPath:    config.CaptiveCoreConfigAppendPath,
 					HTTPPort:            config.CaptiveCoreHTTPPort,
 					NetworkPassphrase:   config.NetworkPassphrase,
 					HistoryArchiveURLs:  []string{config.HistoryArchiveURL},
 					CheckpointFrequency: config.CheckpointFrequency,
 					LedgerHashStore:     ledgerbackend.NewHorizonDBLedgerHashStore(config.HistorySession),
-					Log:                 log.WithField("subservice", "stellar-core"),
+					Log:                 logger,
 					Context:             ctx,
 				},
 			)

services/horizon/internal/init.go

@@ -72,6 +72,7 @@ func initIngester(app *App) {
 		CaptiveCoreBinaryPath:       app.config.CaptiveCoreBinaryPath,
 		CaptiveCoreConfigAppendPath: app.config.CaptiveCoreConfigAppendPath,
 		CaptiveCoreHTTPPort:         app.config.CaptiveCoreHTTPPort,
+		CaptiveCoreLogPath:          app.config.CaptiveCoreLogPath,
 		RemoteCaptiveCoreURL:        app.config.RemoteCaptiveCoreURL,
 		EnableCaptiveCore:           app.config.EnableCaptiveCoreIngestion,
 		DisableStateVerification:    app.config.IngestDisableStateVerification,