From eca8fb90ba6bf96065cfcf9edc52131878ed1910 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Rudowicz?= <michal.rudowicz@fl9.eu>
Date: Sat, 6 Apr 2024 12:08:41 +0200
Subject: [PATCH] Option to store a memory profile once a day

References https://todo.sr.ht/~michalr/hswro-alarm-bot/10
---
 config.go      |  6 ++++++
 debug_utils.go | 36 ++++++++++++++++++++++++++++++++++++
 main.go        |  3 +++
 3 files changed, 45 insertions(+)
 create mode 100644 debug_utils.go

diff --git a/config.go b/config.go
index b14f93a..fbb2f3f 100644
--- a/config.go
+++ b/config.go
@@ -34,6 +34,7 @@ type AppConfig struct {
 	ArmCallbackUrls    []string          `yaml:"arm-callback-urls"`
 	DisarmCallbackUrls []string          `yaml:"disarm-callback-urls"`
 	AlarmCallbackUrls  []string          `yaml:"alarm-callback-urls"`
+	WriteMemoryProfile bool              `yaml:"write-memory-profile"`
 }
 
 func (m *SatelChangeType) UnmarshalYAML(unmarshal func(interface{}) error) error {
@@ -93,6 +94,7 @@ func getCmdLineParams(config *AppConfig, logger *log.Logger) {
 	allowedTypesRaw := flag.String("allowed-types", "", "Satel change types that are allowed. All other types will be discarded. By default all are allowed. Use \",\" to specify multiple types.")
 	allowedIndexesRaw := flag.String("allowed-indexes", "", "Satel indexes (zones?) that are allowed. All other indexes will be discarded. By default all are allowed. Use \",\" to specify multiple indexes.")
 	satelPoolInterval := flag.Duration("pool-interval", 5*time.Second, "How often should the SATEL device be pooled for changes? Default: 5 seconds.")
+	writeMemoryProfile := flag.Bool("write-memory-profile", false, "Whether application should dump its memory profile every 24 hours. Default: false")
 	flag.Parse()
 
 	if len(*satelApiAddr) == 0 || len(*satelApiPort) == 0 || len(*chatIdRaw) == 0 {
@@ -131,6 +133,9 @@ func getCmdLineParams(config *AppConfig, logger *log.Logger) {
 		}
 		allowedIndexes = append(allowedIndexes, int(allowedIndex))
 	}
+	if writeMemoryProfile != nil {
+		config.WriteMemoryProfile = *writeMemoryProfile
+	}
 
 	satelAddr := fmt.Sprintf("%s:%s", *satelApiAddr, *satelApiPort)
 
@@ -146,6 +151,7 @@ func MakeConfig(logger *log.Logger) AppConfig {
 	config.ArmCallbackUrls = []string{}
 	config.DisarmCallbackUrls = []string{}
 	config.AlarmCallbackUrls = []string{}
+	config.WriteMemoryProfile = false
 
 	if len(os.Getenv("NOTIFY_URL_ARM")) != 0 {
 		config.ArmCallbackUrls = append(config.ArmCallbackUrls, os.Getenv("NOTIFY_URL_ARM"))
diff --git a/debug_utils.go b/debug_utils.go
new file mode 100644
index 0000000..45034f8
--- /dev/null
+++ b/debug_utils.go
@@ -0,0 +1,36 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"runtime/pprof"
+	"sync"
+	"time"
+)
+
+func dumpMemoryProfile(log *log.Logger) {
+	path := fmt.Sprintf("%s/hswro_alarm_bot_%s.mprof", os.Getenv("RUNTIME_DIRECTORY"), time.Now().Format(time.RFC3339))
+	f, err := os.Create(path)
+	if err != nil {
+		log.Print("Error dumping memory profile to file: ", err)
+	}
+	pprof.WriteHeapProfile(f)
+	f.Close()
+	log.Print("Dumped memory profile to: ", path)
+}
+
+func WriteMemoryProfilePeriodically(wg *sync.WaitGroup, log *log.Logger, close <-chan interface{}) {
+	go func() {
+		wg.Add(1)
+		defer wg.Done()
+		memoryProfileTicker := time.NewTicker(24 * time.Hour)
+		defer memoryProfileTicker.Stop()
+		select {
+		case <-memoryProfileTicker.C:
+			dumpMemoryProfile(log)
+		case <-close:
+			return
+		}
+	}()
+}
diff --git a/main.go b/main.go
index 07724d4..90dff75 100644
--- a/main.go
+++ b/main.go
@@ -88,7 +88,10 @@ func main() {
 		tgEvents <- GenericMessage{e.BasicEvents}
 	}
 
+	closeDebugTools := make(chan interface{})
+	WriteMemoryProfilePeriodically(&wg, log.New(os.Stderr, "DebugTools", log.Lmicroseconds), closeDebugTools)
 	logger.Print("Closing...")
+	close(closeDebugTools)
 	close(tgEvents)
 	wg.Wait()
 	if cleanShutdown.Load() {