Add http_debugging_endpoint flag to allow disabeling http debug endpo…

…int (fixes google#305)

cmd/mtail/main.go

@@ -73,6 +73,7 @@ var (
 	// Debugging flags.
 	blockProfileRate     = flag.Int("block_profile_rate", 0, "Nanoseconds of block time before goroutine blocking events reported. 0 turns off.  See https://golang.org/pkg/runtime/#SetBlockProfileRate")
 	mutexProfileFraction = flag.Int("mutex_profile_fraction", 0, "Fraction of mutex contention events reported.  0 turns off.  See http://golang.org/pkg/runtime/#SetMutexProfileFraction")
+	httpDebugEndpoints   = flag.Bool("http_debugging_endpoint", true, "Enable debugging endpoints.")
 
 	// Tracing.
 	jaegerEndpoint    = flag.String("jaeger_endpoint", "", "If set, collector endpoint URL of jaeger thrift service")
@@ -207,6 +208,9 @@ func main() {
 	if *dumpBytecode {
 		opts = append(opts, mtail.DumpBytecode)
 	}
+	if *httpDebugEndpoints {
+		opts = append(opts, mtail.HttpDebugEndpoints)
+	}
 	if *syslogUseCurrentYear {
 		opts = append(opts, mtail.SyslogUseCurrentYear)
 	}

internal/mtail/mtail.go

@@ -47,9 +47,10 @@ type Server struct {
 
 	buildInfo BuildInfo // go build information
 
-	programPath string // path to programs to load
-	oneShot     bool   // if set, mtail reads log files from the beginning, once, then exits
-	compileOnly bool   // if set, mtail compiles programs then exits
+	programPath        string // path to programs to load
+	oneShot            bool   // if set, mtail reads log files from the beginning, once, then exits
+	compileOnly        bool   // if set, mtail compiles programs then exit
+	httpDebugEndpoints bool   // if set, mtail will enable debug endpoints
 }
 
 // initRuntime constructs a new runtime and performs the initial load of program files in the program directory.
@@ -96,19 +97,21 @@ func (m *Server) initHTTPServer() error {
 	}
 
 	mux := http.NewServeMux()
-	mux.HandleFunc("/favicon.ico", FaviconHandler)
-	mux.Handle("/", m)
-	mux.Handle("/progz", http.HandlerFunc(m.r.ProgzHandler))
-	mux.HandleFunc("/json", http.HandlerFunc(m.e.HandleJSON))
+	if m.httpDebugEndpoints {
+		mux.HandleFunc("/favicon.ico", FaviconHandler)
+		mux.Handle("/", m)
+		mux.Handle("/progz", http.HandlerFunc(m.r.ProgzHandler))
+		mux.Handle("/debug/vars", expvar.Handler())
+		mux.HandleFunc("/debug/pprof/", pprof.Index)
+		mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+		mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+		mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+		mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+	}
 	mux.Handle("/metrics", promhttp.HandlerFor(m.reg, promhttp.HandlerOpts{}))
+	mux.HandleFunc("/json", http.HandlerFunc(m.e.HandleJSON))
 	mux.HandleFunc("/graphite", http.HandlerFunc(m.e.HandleGraphite))
 	mux.HandleFunc("/varz", http.HandlerFunc(m.e.HandleVarz))
-	mux.Handle("/debug/vars", expvar.Handler())
-	mux.HandleFunc("/debug/pprof/", pprof.Index)
-	mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
-	mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
-	mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
-	mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
 	zpages.Handle(mux, "/")
 
 	srv := &http.Server{

internal/mtail/options.go

@@ -202,6 +202,14 @@ var DumpBytecode = &niladicOption{
 	},
 }
 
+// Debug enables debug http endpoints
+var HttpDebugEndpoints = &niladicOption{
+	func(m *Server) error {
+		m.httpDebugEndpoints = true
+		return nil
+	},
+}
+
 // SyslogUseCurrentYear instructs the Server to use the current year for year-less log timestamp during parsing.
 var SyslogUseCurrentYear = &niladicOption{
 	func(m *Server) error {