adds log level conf to proxyd (#3704)

.changeset/wet-cameras-cover.md

+---
+'@eth-optimism/proxyd': minor
+---
+
+adds server.log_level config

proxyd/cmd/proxyd/main.go

@@ -37,6 +37,21 @@ func main() {
 		log.Crit("error reading config file", "err", err)
 	}
 
+	// update log level from config
+	logLevel, err := log.LvlFromString(config.Server.LogLevel)
+	if err != nil {
+		logLevel = log.LvlInfo
+		if config.Server.LogLevel != "" {
+			log.Warn("invalid server.log_level set: " + config.Server.LogLevel)
+		}
+	}
+	log.Root().SetHandler(
+		log.LvlFilterHandler(
+			logLevel,
+			log.StreamHandler(os.Stdout, log.JSONFormat()),
+		),
+	)
+
 	shutdown, err := proxyd.Start(config)
 	if err != nil {
 		log.Crit("error starting proxyd", "err", err)

proxyd/config.go

@@ -14,6 +14,7 @@ type ServerConfig struct {
 	WSPort            int    `toml:"ws_port"`
 	MaxBodySizeBytes  int64  `toml:"max_body_size_bytes"`
 	MaxConcurrentRPCs int64  `toml:"max_concurrent_rpcs"`
+	LogLevel          string `toml:"log_level"`
 
 	// TimeoutSeconds specifies the maximum time spent serving an HTTP request. Note that isn't used for websocket connections
 	TimeoutSeconds int `toml:"timeout_seconds"`

proxyd/example.config.toml

@@ -19,6 +19,8 @@ ws_port = 8085
 # Maximum client body size, in bytes, that the server will accept.
 max_body_size_bytes = 10485760
 max_concurrent_rpcs = 1000
+# Server log level
+log_level = "info"
 
 [redis]
 # URL to a Redis instance.