Clean up code and update docs

config.go

@@ -7,12 +7,42 @@ import (
 	"os"
 )
 
+// Config type is contains all provided user configuration
 type Config struct {
 	CheckInterval int64 `yaml:"check_interval"`
 	Monitors      []*Monitor
 	Alerts        map[string]*Alert
 }
 
+// IsValid checks config validity and returns true if valid
+func (config Config) IsValid() (isValid bool) {
+	isValid = true
+	for _, monitor := range config.Monitors {
+		if !monitor.IsValid() {
+			log.Printf("ERROR: Invalid monitor configuration: %s", monitor.Name)
+			isValid = false
+		}
+	}
+
+	for _, alert := range config.Alerts {
+		if !alert.IsValid() {
+			log.Printf("ERROR: Invalid alert configuration: %s", alert.Name)
+			isValid = false
+		}
+	}
+
+	return
+}
+
+// Init performs extra initialization on top of loading the config from file
+func (config *Config) Init() {
+	for name, alert := range config.Alerts {
+		alert.Name = name
+		alert.BuildTemplates()
+	}
+}
+
+// LoadConfig will read config from the given path and parse it
 func LoadConfig(filePath string) (config Config) {
 	data, err := ioutil.ReadFile(filePath)
 	if err != nil {
@@ -20,9 +50,8 @@ func LoadConfig(filePath string) (config Config) {
 	}
 
 	// TODO: Decide if this is better expanded here, or only when executing
-	env_expanded := os.ExpandEnv(string(data))
-
-	err = yaml.Unmarshal([]byte(env_expanded), &config)
+	envExpanded := os.ExpandEnv(string(data))
+	err = yaml.Unmarshal([]byte(envExpanded), &config)
 	if err != nil {
 		log.Fatalf("ERROR: %v", err)
 		panic(err)
@@ -30,5 +59,12 @@ func LoadConfig(filePath string) (config Config) {
 
 	log.Printf("config:\n%v\n", config)
 
+	if !config.IsValid() {
+		panic("Cannot continue with invalid configuration")
+	}
+
+	// Finish initializing configuration
+	config.Init()
+
 	return config
 }