internal/debug: add JSON log format and rename logging flags (#22341)

This change adds support for logging JSON records when the --log.json flag is
given. The --debug and --backtrace flags are deprecated and replaced by
--log.debug and --log.backtrace.

While changing this, it was noticed that the --memprofilerate and
--blockprofilerate were ineffective (they were always overridden even if
--pprof.memprofilerate was not set). This is also fixed.

Co-authored-by: Felix Lange <fjl@twurst.com>

internal/debug/flags.go

@@ -41,22 +41,22 @@ var (
 		Usage: "Logging verbosity: 0=silent, 1=error, 2=warn, 3=info, 4=debug, 5=detail",
 		Value: 3,
 	}
-	logjsonFlag = cli.BoolFlag{
-		Name:  "log.json",
-		Usage: "Format logs with JSON",
-	}
 	vmoduleFlag = cli.StringFlag{
 		Name:  "vmodule",
 		Usage: "Per-module verbosity: comma-separated list of <pattern>=<level> (e.g. eth/*=5,p2p=4)",
 		Value: "",
 	}
+	logjsonFlag = cli.BoolFlag{
+		Name:  "log.json",
+		Usage: "Format logs with JSON",
+	}
 	backtraceAtFlag = cli.StringFlag{
-		Name:  "backtrace",
+		Name:  "log.backtrace",
 		Usage: "Request a stack trace at a specific logging statement (e.g. \"block.go:271\")",
 		Value: "",
 	}
 	debugFlag = cli.BoolFlag{
-		Name:  "debug",
+		Name:  "log.debug",
 		Usage: "Prepends log messages with call-site location (file and line number)",
 	}
 	pprofFlag = cli.BoolFlag{
@@ -90,18 +90,69 @@ var (
 		Name:  "trace",
 		Usage: "Write execution trace to the given file",
 	}
+	// (Deprecated April 2020)
+	legacyPprofPortFlag = cli.IntFlag{
+		Name:  "pprofport",
+		Usage: "pprof HTTP server listening port (deprecated, use --pprof.port)",
+		Value: 6060,
+	}
+	legacyPprofAddrFlag = cli.StringFlag{
+		Name:  "pprofaddr",
+		Usage: "pprof HTTP server listening interface (deprecated, use --pprof.addr)",
+		Value: "127.0.0.1",
+	}
+	legacyMemprofilerateFlag = cli.IntFlag{
+		Name:  "memprofilerate",
+		Usage: "Turn on memory profiling with the given rate (deprecated, use --pprof.memprofilerate)",
+		Value: runtime.MemProfileRate,
+	}
+	legacyBlockprofilerateFlag = cli.IntFlag{
+		Name:  "blockprofilerate",
+		Usage: "Turn on block profiling with the given rate (deprecated, use --pprof.blockprofilerate)",
+	}
+	legacyCpuprofileFlag = cli.StringFlag{
+		Name:  "cpuprofile",
+		Usage: "Write CPU profile to the given file (deprecated, use --pprof.cpuprofile)",
+	}
+	legacyBacktraceAtFlag = cli.StringFlag{
+		Name:  "backtrace",
+		Usage: "Request a stack trace at a specific logging statement (e.g. \"block.go:271\") (deprecated, use --log.backtrace)",
+		Value: "",
+	}
+	legacyDebugFlag = cli.BoolFlag{
+		Name:  "debug",
+		Usage: "Prepends log messages with call-site location (file and line number) (deprecated, use --log.debug)",
+	}
 )
 
 // Flags holds all command-line flags required for debugging.
 var Flags = []cli.Flag{
-	verbosityFlag, logjsonFlag, vmoduleFlag, backtraceAtFlag, debugFlag,
+	verbosityFlag,
-	pprofFlag, pprofAddrFlag, pprofPortFlag, memprofilerateFlag,
+	vmoduleFlag,
-	blockprofilerateFlag, cpuprofileFlag, traceFlag,
+	logjsonFlag,
+	backtraceAtFlag,
+	debugFlag,
+	pprofFlag,
+	pprofAddrFlag,
+	pprofPortFlag,
+	memprofilerateFlag,
+	blockprofilerateFlag,
+	cpuprofileFlag,
+	traceFlag,
 }
 
-var (
+// This is the list of deprecated debugging flags.
-	glogger *log.GlogHandler
+var DeprecatedFlags = []cli.Flag{
-)
+	legacyPprofPortFlag,
+	legacyPprofAddrFlag,
+	legacyMemprofilerateFlag,
+	legacyBlockprofilerateFlag,
+	legacyCpuprofileFlag,
+	legacyBacktraceAtFlag,
+	legacyDebugFlag,
+}
+
+var glogger *log.GlogHandler
 
 func init() {
 	glogger = log.NewGlogHandler(log.StreamHandler(os.Stderr, log.TerminalFormat(false)))
@@ -124,17 +175,54 @@ func Setup(ctx *cli.Context) error {
 		ostream = log.StreamHandler(output, log.TerminalFormat(usecolor))
 	}
 	glogger.SetHandler(ostream)
+
 	// logging
-	log.PrintOrigins(ctx.GlobalBool(debugFlag.Name))
+	verbosity := ctx.GlobalInt(verbosityFlag.Name)
-	glogger.Verbosity(log.Lvl(ctx.GlobalInt(verbosityFlag.Name)))
+	glogger.Verbosity(log.Lvl(verbosity))
-	glogger.Vmodule(ctx.GlobalString(vmoduleFlag.Name))
+	vmodule := ctx.GlobalString(vmoduleFlag.Name)
-	glogger.BacktraceAt(ctx.GlobalString(backtraceAtFlag.Name))
+	glogger.Vmodule(vmodule)
+
+	debug := ctx.GlobalBool(debugFlag.Name)
+	if ctx.GlobalIsSet(legacyDebugFlag.Name) {
+		debug = ctx.GlobalBool(legacyDebugFlag.Name)
+		log.Warn("The flag --debug is deprecated and will be removed in the future, please use --log.debug")
+	}
+	if ctx.GlobalIsSet(debugFlag.Name) {
+		debug = ctx.GlobalBool(debugFlag.Name)
+	}
+	log.PrintOrigins(debug)
+
+	backtrace := ctx.GlobalString(backtraceAtFlag.Name)
+	if b := ctx.GlobalString(legacyBacktraceAtFlag.Name); b != "" {
+		backtrace = b
+		log.Warn("The flag --backtrace is deprecated and will be removed in the future, please use --log.backtrace")
+	}
+	if b := ctx.GlobalString(backtraceAtFlag.Name); b != "" {
+		backtrace = b
+	}
+	glogger.BacktraceAt(backtrace)
+
 	log.Root().SetHandler(glogger)
 
 	// profiling, tracing
+	runtime.MemProfileRate = memprofilerateFlag.Value
+	if ctx.GlobalIsSet(legacyMemprofilerateFlag.Name) {
+		runtime.MemProfileRate = ctx.GlobalInt(legacyMemprofilerateFlag.Name)
+		log.Warn("The flag --memprofilerate is deprecated and will be removed in the future, please use --pprof.memprofilerate")
+	}
+	if ctx.GlobalIsSet(memprofilerateFlag.Name) {
 		runtime.MemProfileRate = ctx.GlobalInt(memprofilerateFlag.Name)
+	}
 
-	Handler.SetBlockProfileRate(ctx.GlobalInt(blockprofilerateFlag.Name))
+	blockProfileRate := blockprofilerateFlag.Value
+	if ctx.GlobalIsSet(legacyBlockprofilerateFlag.Name) {
+		blockProfileRate = ctx.GlobalInt(legacyBlockprofilerateFlag.Name)
+		log.Warn("The flag --blockprofilerate is deprecated and will be removed in the future, please use --pprof.blockprofilerate")
+	}
+	if ctx.GlobalIsSet(blockprofilerateFlag.Name) {
+		blockProfileRate = ctx.GlobalInt(blockprofilerateFlag.Name)
+	}
+	Handler.SetBlockProfileRate(blockProfileRate)
 
 	if traceFile := ctx.GlobalString(traceFlag.Name); traceFile != "" {
 		if err := Handler.StartGoTrace(traceFile); err != nil {