Add SQLite option to config process

Ref T529

config/config.go

@@ -60,16 +60,11 @@ type (
 )
 
 func New() *Config {
-	return &Config{
+	c := &Config{
 		Server: ServerCfg{
 			Port: 8080,
 			Bind: "localhost", /* IPV6 support when not using localhost? */
 		},
-		Database: DatabaseCfg{
-			Type: "mysql",
-			Host: "localhost",
-			Port: 3306,
-		},
 		App: AppCfg{
 			Host:           "http://localhost:8080",
 			Theme:          "write",
@@ -81,6 +76,25 @@ func New() *Config {
 			PublicStats:    true,
 		},
 	}
+	c.UseMySQL(true)
+	return c
+}
+
+// UseMySQL resets the Config's Database to use default values for a MySQL setup.
+func (cfg *Config) UseMySQL(fresh bool) {
+	cfg.Database.Type = "mysql"
+	if fresh {
+		cfg.Database.Host = "localhost"
+		cfg.Database.Port = 3306
+	}
+}
+
+// UseSQLite resets the Config's Database to use default values for a SQLite setup.
+func (cfg *Config) UseSQLite(fresh bool) {
+	cfg.Database.Type = "sqlite3"
+	if fresh {
+		cfg.Database.FileName = "writefreely.db"
+	}
 }
 
 func (cfg *Config) IsSecureStandalone() bool {

config/setup.go

@@ -20,10 +20,12 @@ func Configure() (*SetupData, error) {
 
 	data.Config, err = Load()
 	var action string
+	isNewCfg := false
 	if err != nil {
 		fmt.Println("No configuration yet. Creating new.")
 		data.Config = New()
 		action = "generate"
+		isNewCfg = true
 	} else {
 		fmt.Println("Configuration loaded.")
 		action = "update"
@@ -126,6 +128,20 @@ func Configure() (*SetupData, error) {
 	title(" Database setup ")
 	fmt.Println()
 
+	selPrompt = promptui.Select{
+		Templates: selTmpls,
+		Label:     "Database driver",
+		Items:     []string{"MySQL", "SQLite"},
+	}
+	sel, _, err := selPrompt.Run()
+	if err != nil {
+		return data, err
+	}
+
+	if sel == 0 {
+		// Configure for MySQL
+		data.Config.UseMySQL(isNewCfg)
+
 		prompt = promptui.Prompt{
 			Templates: tmpls,
 			Label:     "Username",
@@ -182,6 +198,21 @@ func Configure() (*SetupData, error) {
 			return data, err
 		}
 		data.Config.Database.Port, _ = strconv.Atoi(dbPort) // Ignore error, as we've already validated number
+	} else if sel == 1 {
+		// Configure for SQLite
+		data.Config.UseSQLite(isNewCfg)
+
+		prompt = promptui.Prompt{
+			Templates: tmpls,
+			Label:     "Filename",
+			Validate:  validateNonEmpty,
+			Default:   data.Config.Database.FileName,
+		}
+		data.Config.Database.FileName, err = prompt.Run()
+		if err != nil {
+			return data, err
+		}
+	}
 
 	fmt.Println()
 	title(" App setup ")