Add pprof Debug routes for Sherpa server profiling.

cmd/server/command.go

@@ -27,6 +27,7 @@ func RegisterCommand(rootCmd *cobra.Command) error {
 	serverCfg.RegisterTelemetryConfig(cmd)
 	serverCfg.RegisterClusterConfig(cmd)
 	serverCfg.RegisterMetricProviderConfig(cmd)
+	serverCfg.RegisterDebugConfig(cmd)
 	logCfg.RegisterConfig(cmd)
 	rootCmd.AddCommand(cmd)
 
@@ -53,6 +54,7 @@ func runServer(_ *cobra.Command, _ []string) {
 	}
 
 	cfg := &server.Config{
+		Debug:          serverCfg.GetDebugEnabled(),
 		Cluster:        &clusterConfig,
 		MetricProvider: metricProviderConfig,
 		Server:         &serverConfig,

docs/configuration/README.md

@@ -11,6 +11,7 @@ The Sherpa server can be configured by supplying either CLI flags or using envir
 * `--bind-port` (uint16: 8000) - The HTTP server port to bind to.
 * `--cluster-advertise-addr` (string: "http://127.0.0.1:8000") - The Sherpa server advertise address used for NAT traversal on HTTP redirects.
 * `--cluster-name` (string: "") - Specifies the identifier for the Sherpa cluster.
+* `--debug-enabled` (bool: false) - Specifies if the debugging HTTP endpoints should be enabled.
 * `--log-format` (string: "auto") - Specify the log format ("auto", "zerolog" or "human").
 * `--log-level` (string: "info") - Change the level used for logging.
 * `--log-use-color` (bool: true) - Use ANSI colors in logging output.

pkg/config/server/debug.go

@@ -0,0 +1,30 @@
+package server
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+const configKeyDebugEnable = "debug-enabled"
+
+// GetDebugEnabled is used to identify whether the operator has enabled the server debug API
+// endpoints.
+func GetDebugEnabled() bool { return viper.GetBool(configKeyDebugEnable) }
+
+// RegisterDebugConfig registers the CLI flags used to alter the server debug API endpoints.
+func RegisterDebugConfig(cmd *cobra.Command) {
+	flags := cmd.PersistentFlags()
+
+	{
+		const (
+			key          = configKeyDebugEnable
+			longOpt      = "debug-enabled"
+			defaultValue = false
+			description  = "Specifies if the debugging HTTP endpoints should be enabled"
+		)
+
+		flags.Bool(longOpt, defaultValue, description)
+		_ = viper.BindPFlag(key, flags.Lookup(longOpt))
+		viper.SetDefault(key, defaultValue)
+	}
+}

pkg/config/server/debug_test.go

@@ -0,0 +1,15 @@
+package server
+
+import (
+	"testing"
+
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_DebugConfig(t *testing.T) {
+	fakeCMD := &cobra.Command{}
+	RegisterDebugConfig(fakeCMD)
+	cfg := GetClusterConfig()
+	assert.False(t, GetDebugEnabled(), cfg.Addr)
+}

pkg/server/config.go

@@ -5,6 +5,7 @@ import (
 )
 
 type Config struct {
+	Debug          bool
 	Cluster        *serverCfg.ClusterConfig
 	MetricProvider *serverCfg.MetricProviderConfig
 	Server         *serverCfg.Config
@@ -59,3 +60,17 @@ const (
 	routeSystemInfoName         = "GetSystemInfo"
 	routeSystemInfoPattern      = "/v1/system/info"
 )
+
+// Debug server routes.
+const (
+	routeGetDebugPPROFName           = "GetDebugPPROF"
+	routeGetDebugPPROFPattern        = "/debug/pprof/"
+	routeGetDebugPPROFCMDLineName    = "GetDebugPPROFCMDLine"
+	routeGetDebugPPROFCMDLinePattern = "/debug/pprof/cmdline"
+	routeGetDebugPPROFProfileName    = "GetDebugPPROFProfile"
+	routeGetDebugPPROFProfilePattern = "/debug/pprof/profile"
+	routeGetDebugPPROFSymbolName     = "GetDebugPPROFSymbol"
+	routeGetDebugPPROFSymbolPattern  = "/debug/pprof/symbol"
+	routeGetDebugPPROFTraceName      = "GetDebugPPROFTrace"
+	routeGetDebugPPROFTracePattern   = "/debug/pprof/trace"
+)

pkg/server/routes.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"net/http"
+	"net/http/pprof"
 
 	policyV1 "github.com/jrasell/sherpa/pkg/policy/v1"
 	scaleV1 "github.com/jrasell/sherpa/pkg/scale/v1"
@@ -33,6 +34,12 @@ func (h *HTTPServer) setupRoutes() *router.RouteTable {
 	policyRoutes := h.setupPolicyRoutes()
 	r = append(r, policyRoutes)
 
+	// Setup the server debug routes if enabled.
+	if h.cfg.Debug {
+		debugRoutes := h.setupDebugRoutes()
+		r = append(r, debugRoutes)
+	}
+
 	// Setup the UI routes if it is enabled.
 	if h.cfg.Server.UI {
 		uiRoutes := h.setupUIRoutes()
@@ -213,3 +220,40 @@ func (h *HTTPServer) setupAPIPolicyRoutes() []router.Route {
 		},
 	}
 }
+
+func (h *HTTPServer) setupDebugRoutes() []router.Route {
+	h.logger.Debug().Msg("setting up server Debug routes")
+
+	return router.Routes{
+		router.Route{
+			Name:        routeGetDebugPPROFName,
+			Method:      http.MethodGet,
+			Pattern:     routeGetDebugPPROFPattern,
+			HandlerFunc: pprof.Index,
+		},
+		router.Route{
+			Name:        routeGetDebugPPROFCMDLineName,
+			Method:      http.MethodGet,
+			Pattern:     routeGetDebugPPROFCMDLinePattern,
+			HandlerFunc: pprof.Cmdline,
+		},
+		router.Route{
+			Name:        routeGetDebugPPROFProfileName,
+			Method:      http.MethodGet,
+			Pattern:     routeGetDebugPPROFProfilePattern,
+			HandlerFunc: pprof.Profile,
+		},
+		router.Route{
+			Name:        routeGetDebugPPROFSymbolName,
+			Method:      http.MethodGet,
+			Pattern:     routeGetDebugPPROFSymbolPattern,
+			HandlerFunc: pprof.Symbol,
+		},
+		router.Route{
+			Name:        routeGetDebugPPROFTraceName,
+			Method:      http.MethodGet,
+			Pattern:     routeGetDebugPPROFTracePattern,
+			HandlerFunc: pprof.Trace,
+		},
+	}
+}