Make config handling simpler

3 files changed, 23 insertions, 26 deletions

diff --git a/cmd/mirror/main.go b/cmd/mirror/main.go
index 4d2e712..8276a10 100644
--- a/cmd/mirror/main.go
+++ b/cmd/mirror/main.go
@@ -32,11 +32,10 @@ func exitOnError(err error) {
 func main() {
 	flags := ParseFlags()
 
-	var cfg service.Config
-	err := service.ApplyFileConfig(&cfg, flags.Config)
+	cfg, err := service.ReadConfig(flags.Config)
 	exitOnError(err)
 
-	srv, err := service.NewService(&cfg)
+	srv, err := service.NewService(cfg)
 	exitOnError(err)
 
 	err = srv.Run()
diff --git a/internal/service/config.go b/internal/service/config.go
index 0c42755..27368b3 100644
--- a/internal/service/config.go
+++ b/internal/service/config.go
@@ -49,36 +49,33 @@ var DefaultConfig = Config{
 	},
 }
 
-func (c *Config) Apply(src Config) {
-	if c.MaxInterval.Duration == 0 && src.MaxInterval.Duration != 0 {
-		c.MaxInterval = src.MaxInterval
-	}
-	if c.MinInterval.Duration == 0 && src.MinInterval.Duration != 0 {
-		c.MinInterval = src.MinInterval
-	}
-	if len(c.Mirrors) == 0 {
-		c.Mirrors = src.Mirrors
-	}
-}
-
-// ApplyFileConfig loads the configuration described by the given yaml file.
-func ApplyFileConfig(cfg *Config, filePath string) error {
-	var ret Config
+func ReadConfig(fp string) (*Config, error) {
+	var config Config
 
-	f, err := os.Open(filePath)
+	f, err := os.Open(fp)
 	if os.IsNotExist(err) {
-		return nil
+		return nil, nil
 	} else if err != nil {
-		return err
+		return nil, err
 	}
 	defer f.Close()
 
-	_, err = toml.NewDecoder(f).Decode(&ret)
+	_, err = toml.NewDecoder(f).Decode(&config)
 	if err != nil {
-		return fmt.Errorf("loading configuration file: %w", err)
+		return nil, fmt.Errorf("loading configuration file: %w", err)
 	}
 
-	cfg.Apply(ret)
+	return &config, nil
+}
 
-	return nil
+func (c *Config) Merge(src *Config) {
+	if c.MaxInterval.Duration == 0 && src.MaxInterval.Duration != 0 {
+		c.MaxInterval = src.MaxInterval
+	}
+	if c.MinInterval.Duration == 0 && src.MinInterval.Duration != 0 {
+		c.MinInterval = src.MinInterval
+	}
+	if len(c.Mirrors) == 0 {
+		c.Mirrors = src.Mirrors
+	}
 }
diff --git a/internal/service/service.go b/internal/service/service.go
index 9fbacfb..637a1cf 100644
--- a/internal/service/service.go
+++ b/internal/service/service.go
@@ -31,7 +31,8 @@ type Service struct {
 }
 
 func NewService(cfg *Config) (*Service, error) {
-	cfg.Apply(DefaultConfig)
+	// Apply  defaults
+	cfg.Merge(&DefaultConfig)
 
 	for _, cmd := range requiredCommands {
 		if err := internal.RequireCommand(cmd); err != nil {