Merge pull request #27 from kaleido-io/debug

add debug endpoint

Author: peterbroadhurst

config.md

@@ -73,6 +73,12 @@ nav_order: 2
 |methods| CORS setting to control the allowed methods|`string`|`[GET POST PUT PATCH DELETE]`
 |origins|CORS setting to control the allowed origins|`string`|`[*]`
 
+## debug
+
+|Key|Description|Type|Default Value|
+|---|-----------|----|-------------|
+|port|An HTTP port on which to enable the go debugger|`int`|`-1`
+
 ## eventstreams
 
 |Key|Description|Type|Default Value|

internal/tmconfig/tmconfig.go

@@ -56,6 +56,7 @@ var (
 	PersistenceLevelDBSyncWrites                  = ffc("persistence.leveldb.syncWrites")
 	APIDefaultRequestTimeout                      = ffc("api.defaultRequestTimeout")
 	APIMaxRequestTimeout                          = ffc("api.maxRequestTimeout")
+	DebugPort                                     = ffc("debug.port")
 )
 
 var APIConfig config.Section
@@ -100,6 +101,7 @@ func setDefaults() {
 	viper.SetDefault(string(EventStreamsRetryInitDelay), "250ms")
 	viper.SetDefault(string(EventStreamsRetryMaxDelay), "30s")
 	viper.SetDefault(string(EventStreamsRetryFactor), 2.0)
+	viper.SetDefault(string(DebugPort), -1)
 }
 
 func Reset() {

internal/tmmsgs/en_config_descriptions.go

@@ -36,6 +36,8 @@ var (
 	ConfigAPIWriteTimeout          = ffc("config.api.writeTimeout", "The maximum time to wait when writing to a HTTP connection", i18n.TimeDurationType)
 	ConfigAPIShutdownTimeout       = ffc("config.api.shutdownTimeout", "The maximum amount of time to wait for any open HTTP requests to finish before shutting down the HTTP server", i18n.TimeDurationType)
 
+	ConfigDebugPort = ffc("config.debug.port", "An HTTP port on which to enable the go debugger", i18n.IntType)
+
 	ConfigConfirmationsBlockCacheSize           = ffc("config.confirmations.blockCacheSize", "The maximum number of block headers to keep in the cache", i18n.IntType)
 	ConfigConfirmationsBlockQueueLength         = ffc("config.confirmations.blockQueueLength", "Internal queue length for notifying the confirmations manager of new blocks", i18n.IntType)
 	ConfigConfirmationsNotificationsQueueLength = ffc("config.confirmations.notificationQueueLength", "Internal queue length for notifying the confirmations manager of new transactions/events", i18n.IntType)

pkg/fftm/api.go

@@ -18,13 +18,17 @@ package fftm
 
 import (
 	"encoding/json"
+	"fmt"
 	"net/http"
+	"net/http/pprof"
+	"time"
 
 	"github.com/ghodss/yaml"
 	"github.com/gorilla/mux"
 	"github.com/hyperledger/firefly-common/pkg/config"
 	"github.com/hyperledger/firefly-common/pkg/ffapi"
 	"github.com/hyperledger/firefly-common/pkg/i18n"
+	"github.com/hyperledger/firefly-common/pkg/log"
 	"github.com/hyperledger/firefly-transaction-manager/internal/tmconfig"
 )
 
@@ -77,3 +81,27 @@ func (m *manager) router() *mux.Router {
 func (m *manager) runAPIServer() {
 	m.apiServer.ServeHTTP(m.ctx)
 }
+
+func (m *manager) runDebugServer() {
+	var debugServer *http.Server
+	debugPort := config.GetInt(tmconfig.DebugPort)
+
+	defer func() {
+		if debugServer != nil {
+			_ = debugServer.Close()
+		}
+		close(m.debugServerDone)
+	}()
+
+	if debugPort >= 0 {
+		r := mux.NewRouter()
+		r.PathPrefix("/debug/pprof/cmdline").HandlerFunc(pprof.Cmdline)
+		r.PathPrefix("/debug/pprof/profile").HandlerFunc(pprof.Profile)
+		r.PathPrefix("/debug/pprof/symbol").HandlerFunc(pprof.Symbol)
+		r.PathPrefix("/debug/pprof/trace").HandlerFunc(pprof.Trace)
+		r.PathPrefix("/debug/pprof/").HandlerFunc(pprof.Index)
+		debugServer = &http.Server{Addr: fmt.Sprintf("localhost:%d", debugPort), Handler: r, ReadHeaderTimeout: 30 * time.Second}
+		log.L(m.ctx).Debugf("Debug HTTP endpoint listening on localhost:%d", debugPort)
+		_ = debugServer.ListenAndServe()
+	}
+}

pkg/fftm/manager.go

@@ -87,6 +87,7 @@ type manager struct {
 	blockListenerDone       chan struct{}
 	started                 bool
 	apiServerDone           chan error
+	debugServerDone         chan struct{}
 
 	policyLoopInterval time.Duration
 	nonceStateTimeout  time.Duration
@@ -182,6 +183,8 @@ func (m *manager) Start() error {
 		return err
 	}
 
+	m.debugServerDone = make(chan struct{})
+	go m.runDebugServer()
 	go m.runAPIServer()
 	m.policyLoopDone = make(chan struct{})
 	m.markInflightStale()
@@ -199,6 +202,7 @@ func (m *manager) Close() {
 		<-m.apiServerDone
 		<-m.policyLoopDone
 		<-m.blockListenerDone
+		<-m.debugServerDone
 
 		streams := []events.Stream{}
 		m.mux.Lock()