regenerate template cache on a timer

default:12hr

README.md

@@ -8,6 +8,7 @@ Code for the [burning.moe](https://burning.moe) homepage
   - [cleanenv](https://github.com/ilyakaznacheev/cleanenv)
   - [log](https://github.com/charmbracelet/log)
   - [mage](https://github.com/magefile/mage)
+  - [tasks](https://github.com/madflojo/tasks)
 - written using [helix](https://helix-editor.com/)
 - tested on [void linux](https://voidlinux.org/)
 - hosted on [debian linux](https://www.debian.org/)

cmd/web/main.go

@@ -5,10 +5,13 @@ package main
 import (
 	"fmt"
 	"net/http"
+	"time"
 
 	"git.burning.moe/celediel/burning.moe/internal/config"
 	"git.burning.moe/celediel/burning.moe/internal/handlers"
 	"git.burning.moe/celediel/burning.moe/internal/render"
+
+	"github.com/madflojo/tasks"
 )
 
 // App wide config data and such
@@ -22,6 +25,26 @@ func main() {
 	handlers.Initialise(&app)
 	render.Initialise(&app)
 
+	// Setup task to regenerate template cache
+	scheduler := tasks.New()
+	defer scheduler.Stop()
+	id, err := scheduler.Add(&tasks.Task{
+		Interval: time.Duration(app.CacheTimer),
+		TaskFunc: func() error {
+			err := render.RegenerateTemplateCache()
+			if err != nil {
+				return err
+			}
+			app.Logger.Infof("Regenerate cache job finished at %s", time.Now())
+			return nil
+		},
+		ErrFunc: func(err error) {
+			app.Logger.Error("Error in template regeneration cache job!", "err", err)
+		},
+	})
+
+	app.Logger.Info("Started cache regeneration task.", "interval", app.CacheTimer.String(), "id", id)
+
 	// Initialise the webserver
 	srv := &http.Server{
 		Addr:    fmt.Sprintf(":%d", app.ListenPort),
@@ -30,7 +53,7 @@ func main() {
 
 	// and finally, start the server
 	app.Logger.Printf("Starting HTTP Server on port %d", app.ListenPort)
-	err := srv.ListenAndServe()
+	err = srv.ListenAndServe()
 	if err != nil {
 		app.Logger.Fatal("Failed to start HTTP Server!", "err", err)
 	}

go.mod

@@ -6,6 +6,7 @@ require (
 	github.com/charmbracelet/log v0.3.1
 	github.com/go-chi/chi/v5 v5.0.11
 	github.com/ilyakaznacheev/cleanenv v1.5.0
+	github.com/madflojo/tasks v1.1.0
 	github.com/magefile/mage v1.15.0
 )
 
@@ -21,6 +22,7 @@ require (
 	github.com/muesli/reflow v0.3.0 // indirect
 	github.com/muesli/termenv v0.15.2 // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect
+	github.com/rs/xid v1.5.0 // indirect
 	golang.org/x/exp v0.0.0-20231006140011-7918f672742d // indirect
 	golang.org/x/sys v0.13.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -19,6 +19,8 @@ github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
 github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
 github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
+github.com/madflojo/tasks v1.1.0 h1:CHQhzdot1MdAlWLw/VOa69SRZ28VQ+gbSf9lI55aSsM=
+github.com/madflojo/tasks v1.1.0/go.mod h1:h0cJ1gYqIBzczyg0tyEqGAbIltbxxhUsMMKnaQa9IPc=
 github.com/magefile/mage v1.15.0 h1:BvGheCMAsG3bWUDbZ8AyXXpCNwU9u5CB6sM+HNb9HYg=
 github.com/magefile/mage v1.15.0/go.mod h1:z5UZb/iS3GoOSn0JgWuiw7dxlurVYTu+/jHXqQg881A=
 github.com/mattn/go-isatty v0.0.18 h1:DOKFKCQ7FNG2L1rbrmstDN4QVRdS89Nkh85u68Uwp98=
@@ -35,6 +37,8 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/rs/xid v1.5.0 h1:mKX4bl4iPYJtEIxp6CYiUuLQ/8DYMoz0PUdtGgMFRVc=
+github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 golang.org/x/exp v0.0.0-20231006140011-7918f672742d h1:jtJma62tbqLibJ5sFQz8bKtEM8rJBtfilJ2qTU199MI=

internal/config/config.go

@@ -12,25 +12,28 @@ import (
 
 // AppConfig contains data to be accessed across the app.
 type AppConfig struct {
+	CacheTimer    time.Duration
 	ListenPort    uint16
-	TemplateCache models.TemplateCache
-	UseCache      bool
 	Logger        *log.Logger
 	LogLevel      log.Level
+	TemplateCache models.TemplateCache
+	UseCache      bool
 }
 
 // defaluts contains default settings that are used if no environmental variables are set
 var defaults = &AppConfig{
+	CacheTimer: time.Hour * 12,
 	ListenPort: 9001,
-	UseCache:   true,
 	LogLevel:   log.InfoLevel,
+	UseCache:   true,
 }
 
 // ConfigDatabase contains data to be loaded from environmental variables
 type ConfigDatabase struct {
-	Port     uint16 `env:"PORT" env-default:"9001" env-description:"server port"`
+	CacheTimer time.Duration `env:"CACHETIMER" env-description:"How often to automatically regenerate template cache."`
-	LogLevel string `env:"LOGLEVEL" env-default:"warn" env-description:"Logging level. Default: warn, Possible values: debug info warn error fatal none"`
+	LogLevel   string        `env:"LOGLEVEL" env-description:"Logging level. Default: warn, Possible values: debug info warn error fatal none"`
-	UseCache bool   `env:"CACHE" env-default:"true" env-description:"Use template cache"`
+	Port       uint16        `env:"PORT" env-description:"server port"`
+	UseCache   bool          `env:"CACHE" env-description:"Use template cache"`
 }
 
 // Initialises the app wide AppConfig, loads values from environment, and set up the Logger
@@ -47,6 +50,7 @@ func Initialise() AppConfig {
 	if cfg, err := loadConfig(); err == nil {
 		app.ListenPort = cfg.Port
 		app.UseCache = cfg.UseCache
+		app.CacheTimer = cfg.CacheTimer
 		app.LogLevel, err = log.ParseLevel(cfg.LogLevel)
 		if err != nil {
 			app.LogLevel = defaults.LogLevel
@@ -56,7 +60,10 @@ func Initialise() AppConfig {
 	}
 
 	app.Logger.SetLevel(app.LogLevel)
-	app.Logger.Debug("Loaded config from environment:", "port", app.ListenPort, "useCache", app.UseCache, "log_level", app.LogLevel)
+	app.Logger.Debug("Loaded config from environment:",
+		"port", app.ListenPort, "useCache", app.UseCache,
+		"log_level", app.LogLevel, "cacheTimer", app.CacheTimer,
+	)
 
 	return app
 }

internal/render/render.go

@@ -37,7 +37,10 @@ func Initialise(a *config.AppConfig) {
 func RenderTemplate(w http.ResponseWriter, filename string) {
 	// TODO: implement this better
 	if !app.UseCache {
-		regenerateTemplateCache()
+		err := RegenerateTemplateCache()
+		if err != nil {
+			app.Logger.Fatal("Regenerating template cache failed!", err, "err")
+		}
 	}
 
 	template, err := GetTemplateFromCache(filename)
@@ -59,7 +62,10 @@ func RenderTemplate(w http.ResponseWriter, filename string) {
 
 func RenderTemplateWithData(w http.ResponseWriter, filename string, data *models.TemplateData) {
 	if !app.UseCache {
-		regenerateTemplateCache()
+		err := RegenerateTemplateCache()
+		if err != nil {
+			app.Logger.Fatal("Regenerating template cache failed!", err, "err")
+		}
 	}
 
 	template, err := GetTemplateFromCache(filename)
@@ -104,13 +110,15 @@ func GetOrGenerateTemplateData(filename string) (*models.TemplateData, error) {
 	return &data, nil
 }
 
-// regenerateTemplateCache regenerates the template cache
+// RegenerateTemplateCache regenerates the template cache
-func regenerateTemplateCache() {
+func RegenerateTemplateCache() error {
 	c, err := generateNewTemplateCache()
 	if err != nil {
-		app.Logger.Fatal("Error generating template cache, bailing out!", "err", err)
+		// app.Logger.Fatal("Error generating template cache, bailing out!", "err", err)
+		return err
 	}
 	app.TemplateCache = c
+	return nil
 
 }