From 31591d694c4540e0cf55476f998fd588f66b767a Mon Sep 17 00:00:00 2001
From: Jan-Lukas Else <mail@jlelse.de>
Date: Tue, 4 Aug 2020 19:42:09 +0200
Subject: [PATCH] Simplify configuration initialization

---
 cache.go    |  10 ++---
 config.go   | 113 +++++++++++++++++++---------------------------------
 database.go |   2 +-
 go.mod      |   4 +-
 go.sum      |   8 ++--
 http.go     |  14 +++----
 render.go   |   2 +-
 7 files changed, 60 insertions(+), 93 deletions(-)

diff --git a/cache.go b/cache.go
index 831a3f5..8ed6a1a 100644
--- a/cache.go
+++ b/cache.go
@@ -13,7 +13,7 @@ func cacheMiddleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		requestUrl, _ := url.ParseRequestURI(r.RequestURI)
 		path := slashTrimmedPath(r)
-		if appConfig.cache.enable &&
+		if appConfig.Cache.Enable &&
 			// check bypass query
 			!(requestUrl != nil && requestUrl.Query().Get("cache") == "0") {
 			cacheTime, header, body := getCache(r.Context(), path)
@@ -27,7 +27,7 @@ func cacheMiddleware(next http.Handler) http.Handler {
 					w.Header()[k] = v
 				}
 				now := time.Now()
-				setCacheHeaders(w, now.Format(time.RFC1123), time.Unix(now.Unix()+appConfig.cache.expiration, 0).Format(time.RFC1123))
+				setCacheHeaders(w, now.Format(time.RFC1123), time.Unix(now.Unix()+appConfig.Cache.Expiration, 0).Format(time.RFC1123))
 				w.Header().Set("GoBlog-Cache", "MISS")
 				w.WriteHeader(code)
 				_, _ = w.Write(recorder.Body.Bytes())
@@ -38,7 +38,7 @@ func cacheMiddleware(next http.Handler) http.Handler {
 				return
 			}
 			cacheTimeString := time.Unix(cacheTime, 0).Format(time.RFC1123)
-			expiresTimeString := time.Unix(cacheTime+appConfig.cache.expiration, 0).Format(time.RFC1123)
+			expiresTimeString := time.Unix(cacheTime+appConfig.Cache.Expiration, 0).Format(time.RFC1123)
 			// check conditional request
 			ifModifiedSinceHeader := r.Header.Get("If-Modified-Since")
 			if ifModifiedSinceHeader != "" && ifModifiedSinceHeader == cacheTimeString {
@@ -70,7 +70,7 @@ func setCacheHeaders(w http.ResponseWriter, cacheTimeString string, expiresTimeS
 
 func getCache(context context.Context, path string) (creationTime int64, header map[string][]string, body []byte) {
 	var headerBytes []byte
-	allowedTime := time.Now().Unix() - appConfig.cache.expiration
+	allowedTime := time.Now().Unix() - appConfig.Cache.Expiration
 	row := appDb.QueryRowContext(context, "select COALESCE(time, 0), header, body from cache where path=? and time>=?", path, allowedTime)
 	_ = row.Scan(&creationTime, &headerBytes, &body)
 	header = make(map[string][]string)
@@ -85,7 +85,7 @@ func saveCache(path string, now time.Time, header map[string][]string, body []by
 	if err != nil {
 		return
 	}
-	_, _ = tx.Exec("delete from cache where time<?;", now.Unix()-appConfig.cache.expiration)
+	_, _ = tx.Exec("delete from cache where time<?;", now.Unix()-appConfig.Cache.Expiration)
 	_, _ = tx.Exec("insert or replace into cache (path, time, header, body) values (?, ?, ?, ?);", path, now.Unix(), headerBytes, body)
 	_ = tx.Commit()
 	finishWritingToDb()
diff --git a/config.go b/config.go
index 8add2b5..c2d9e5f 100644
--- a/config.go
+++ b/config.go
@@ -5,52 +5,46 @@ import (
 )
 
 type config struct {
-	server *configServer
-	db     *configDb
-	cache  *configCache
-	blog   *configBlog
-	user   *configUser
+	Server *configServer `mapstructure:"server"`
+	Db     *configDb     `mapstructure:"database"`
+	Cache  *configCache  `mapstructure:"cache"`
+	Blog   *configBlog   `mapstructure:"blog"`
+	User   *configUser   `mapstructure:"user"`
 }
 
 type configServer struct {
-	logging         bool
-	port            int
-	domain          string
-	publicHttps     bool
-	letsEncryptMail string
-	localHttps      bool
+	Logging         bool   `mapstructure:"logging"`
+	Port            int    `mapstructure:"port"`
+	Domain          string `mapstructure:"domain"`
+	PublicHttps     bool   `mapstructure:"publicHttps"`
+	LetsEncryptMail string `mapstructure:"letsEncryptMail"`
+	LocalHttps      bool   `mapstructure:"localHttps"`
 }
 
 type configDb struct {
-	file string
+	File string `mapstructure:"file"`
 }
 
 type configCache struct {
-	enable     bool
-	expiration int64
+	Enable     bool  `mapstructure:"enable"`
+	Expiration int64 `mapstructure:"expiration"`
 }
 
 // exposed to templates via function "blog"
 type configBlog struct {
 	// Language of the blog, e.g. "en" or "de"
-	Lang string
+	Lang string `mapstructure:"lang"`
 	// Title of the blog, e.g. "My blog"
-	Title string
+	Title string `mapstructure:"title"`
 }
 
 type configUser struct {
-	nick     string
-	name     string
-	password string
+	Nick     string `mapstructure:"nick"`
+	Name     string `mapstructure:"name"`
+	Password string `mapstructure:"password"`
 }
 
-var appConfig = &config{
-	server: &configServer{},
-	db:     &configDb{},
-	cache:  &configCache{},
-	blog:   &configBlog{},
-	user:   &configUser{},
-}
+var appConfig = &config{}
 
 func initConfig() error {
 	viper.SetConfigName("config")
@@ -59,52 +53,25 @@ func initConfig() error {
 	if err != nil {
 		return err
 	}
-	// Server
-	serverLogging := "server.logging"
-	viper.SetDefault(serverLogging, false)
-	appConfig.server.logging = viper.GetBool(serverLogging)
-	serverPort := "server.port"
-	viper.SetDefault(serverPort, 8080)
-	appConfig.server.port = viper.GetInt(serverPort)
-	serverDomain := "server.domain"
-	viper.SetDefault(serverDomain, "example.com")
-	appConfig.server.domain = viper.GetString(serverDomain)
-	serverPublicHttps := "server.publicHttps"
-	viper.SetDefault(serverPublicHttps, false)
-	appConfig.server.publicHttps = viper.GetBool(serverPublicHttps)
-	serverLetsEncryptMail := "server.letsEncryptMail"
-	viper.SetDefault(serverLetsEncryptMail, "mail@example.com")
-	appConfig.server.letsEncryptMail = viper.GetString(serverLetsEncryptMail)
-	serverLocalHttps := "server.localHttps"
-	viper.SetDefault(serverLocalHttps, false)
-	appConfig.server.localHttps = viper.GetBool(serverLocalHttps)
-	// Database
-	databaseFile := "database.file"
-	viper.SetDefault(databaseFile, "data/db.sqlite")
-	appConfig.db.file = viper.GetString(databaseFile)
-	// Caching
-	cacheEnable := "cache.enable"
-	viper.SetDefault(cacheEnable, true)
-	appConfig.cache.enable = viper.GetBool(cacheEnable)
-	cacheExpiration := "cache.expiration"
-	viper.SetDefault(cacheExpiration, 600)
-	appConfig.cache.expiration = viper.GetInt64(cacheExpiration)
-	// Blog meta
-	blogLang := "blog.lang"
-	viper.SetDefault(blogLang, "en")
-	appConfig.blog.Lang = viper.GetString(blogLang)
-	blogTitle := "blog.title"
-	viper.SetDefault(blogTitle, "My blog")
-	appConfig.blog.Title = viper.GetString(blogTitle)
-	// User
-	userNick := "user.nick"
-	viper.SetDefault(userNick, "admin")
-	appConfig.user.nick = viper.GetString(userNick)
-	userName := "user.name"
-	viper.SetDefault(userName, "Admin")
-	appConfig.user.name = viper.GetString(userName)
-	userPassword := "user.password"
-	viper.SetDefault(userPassword, "secret")
-	appConfig.user.password = viper.GetString(userPassword)
+	// Defaults
+	viper.SetDefault("server.logging", false)
+	viper.SetDefault("server.port", 8080)
+	viper.SetDefault("server.domain", "example.com")
+	viper.SetDefault("server.publicHttps", false)
+	viper.SetDefault("server.letsEncryptMail", "mail@example.com")
+	viper.SetDefault("server.localHttps", false)
+	viper.SetDefault("database.file", "data/db.sqlite")
+	viper.SetDefault("cache.enable", true)
+	viper.SetDefault("cache.expiration", 600)
+	viper.SetDefault("blog.lang", "en")
+	viper.SetDefault("blog.title", "My blog")
+	viper.SetDefault("user.nick", "admin")
+	viper.SetDefault("user.name", "Admin")
+	viper.SetDefault("user.password", "secret")
+	// Unmarshal config
+	err = viper.Unmarshal(appConfig)
+	if err != nil {
+		return err
+	}
 	return nil
 }
diff --git a/database.go b/database.go
index 012493d..a81b9c2 100644
--- a/database.go
+++ b/database.go
@@ -10,7 +10,7 @@ var appDb *sql.DB
 var appDbWriteMutex = &sync.Mutex{}
 
 func initDatabase() (err error) {
-	appDb, err = sql.Open("sqlite3", appConfig.db.file+"?cache=shared&mode=rwc&_journal_mode=WAL")
+	appDb, err = sql.Open("sqlite3", appConfig.Db.File+"?cache=shared&mode=rwc&_journal_mode=WAL")
 	if err != nil {
 		return err
 	}
diff --git a/go.mod b/go.mod
index 0b604a1..38cef4c 100644
--- a/go.mod
+++ b/go.mod
@@ -20,7 +20,7 @@ require (
 	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
 	github.com/pelletier/go-toml v1.8.0 // indirect
 	github.com/smartystreets/assertions v1.1.1 // indirect
-	github.com/spf13/afero v1.3.2 // indirect
+	github.com/spf13/afero v1.3.3 // indirect
 	github.com/spf13/cast v1.3.1 // indirect
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/viper v1.7.1
@@ -30,7 +30,7 @@ require (
 	golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de // indirect
 	golang.org/x/net v0.0.0-20200707034311-ab3426394381 // indirect
 	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208 // indirect
-	golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1 // indirect
+	golang.org/x/sys v0.0.0-20200803210538-64077c9b5642 // indirect
 	golang.org/x/text v0.3.3 // indirect
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/ini.v1 v1.57.0 // indirect
diff --git a/go.sum b/go.sum
index ac5df2d..9831fc6 100644
--- a/go.sum
+++ b/go.sum
@@ -357,8 +357,8 @@ github.com/soheilhy/cmux v0.1.4/go.mod h1:IM3LyeVVIOuxMH7sFAkER9+bJ4dT7Ms6E4xg4k
 github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
 github.com/spf13/afero v1.1.2 h1:m8/z1t7/fwjysjQRYbP0RD+bUIF/8tJwPdEZsI83ACI=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
-github.com/spf13/afero v1.3.2 h1:GDarE4TJQI52kYSbSAmLiId1Elfj+xgSDqrUZxFhxlU=
-github.com/spf13/afero v1.3.2/go.mod h1:5KUK8ByomD5Ti5Artl0RtHeI5pTF7MIDuXL3yY520V4=
+github.com/spf13/afero v1.3.3 h1:p5gZEKLYoL7wh8VrJesMaYeNxdEd1v3cb4irOk9zB54=
+github.com/spf13/afero v1.3.3/go.mod h1:5KUK8ByomD5Ti5Artl0RtHeI5pTF7MIDuXL3yY520V4=
 github.com/spf13/cast v1.3.0 h1:oget//CVOEoFewqQxwr0Ej5yjygnqGkvggSE/gB35Q8=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
 github.com/spf13/cast v1.3.1 h1:nFm6S0SMdyzrzcmThSipiEubIDy8WEXKNZ0UOgiRpng=
@@ -540,8 +540,8 @@ golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200724161237-0e2f3a69832c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1 h1:sIky/MyNRSHTrdxfsiUSS4WIAMvInbeXljJz+jDjeYE=
-golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200803210538-64077c9b5642 h1:B6caxRw+hozq68X2MY7jEpZh/cr4/aHLv9xU8Kkadrw=
+golang.org/x/sys v0.0.0-20200803210538-64077c9b5642/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/http.go b/http.go
index ab91c91..49fc382 100644
--- a/http.go
+++ b/http.go
@@ -21,11 +21,11 @@ func startServer() (err error) {
 		return
 	}
 	d.swapHandler(h)
-	localAddress := ":" + strconv.Itoa(appConfig.server.port)
-	if appConfig.server.publicHttps {
+	localAddress := ":" + strconv.Itoa(appConfig.Server.Port)
+	if appConfig.Server.PublicHttps {
 		initPublicHTTPS()
-		err = certmagic.HTTPS([]string{appConfig.server.domain}, d)
-	} else if appConfig.server.localHttps {
+		err = certmagic.HTTPS([]string{appConfig.Server.Domain}, d)
+	} else if appConfig.Server.LocalHttps {
 		err = http.ListenAndServeTLS(localAddress, "https/server.crt", "https/server.key", d)
 	} else {
 		err = http.ListenAndServe(localAddress, d)
@@ -36,7 +36,7 @@ func startServer() (err error) {
 func initPublicHTTPS() {
 	certmagic.Default.Storage = &certmagic.FileStorage{Path: "certmagic"}
 	certmagic.DefaultACME.Agreed = true
-	certmagic.DefaultACME.Email = appConfig.server.letsEncryptMail
+	certmagic.DefaultACME.Email = appConfig.Server.LetsEncryptMail
 	certmagic.DefaultACME.CA = certmagic.LetsEncryptProductionCA
 }
 
@@ -52,7 +52,7 @@ func reloadRouter() error {
 func buildHandler() (http.Handler, error) {
 	r := chi.NewRouter()
 
-	if appConfig.server.logging {
+	if appConfig.Server.Logging {
 		r.Use(middleware.RealIP)
 		r.Use(middleware.Logger)
 	}
@@ -62,7 +62,7 @@ func buildHandler() (http.Handler, error) {
 
 	r.Route("/api", func(apiRouter chi.Router) {
 		apiRouter.Use(middleware.BasicAuth("API", map[string]string{
-			appConfig.user.nick: appConfig.user.password,
+			appConfig.User.Nick: appConfig.User.Password,
 		}))
 		apiRouter.Post("/post", apiPostCreate)
 		apiRouter.Delete("/post", apiPostDelete)
diff --git a/render.go b/render.go
index ddce80d..9c63e59 100644
--- a/render.go
+++ b/render.go
@@ -18,7 +18,7 @@ var templateFunctions template.FuncMap
 func initRendering() {
 	templateFunctions = template.FuncMap{
 		"blog": func() *configBlog {
-			return appConfig.blog
+			return appConfig.Blog
 		},
 		"md": func(content string) template.HTML {
 			htmlContent, err := renderMarkdown(content)