fix: add proper error when missing rules file

cmd/clean.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"log"
+	"os"
 
 	"github.com/spf13/cobra"
 
@@ -23,6 +24,10 @@ var cleanCmd = &cobra.Command{
 
 		_, err := rules.LoadRulesConfig(rulesFilePath)
 		if err != nil {
+			if _, rulesMissing := err.(*rules.MissingRulesFile); rulesMissing {
+				log.Println("Couldn't find rules file. Please run `antidot update`.")
+				os.Exit(2)
+			}
 			log.Fatalln("Failed to read rules file: ", err)
 		}
 

internal/rules/config.go

@@ -3,11 +3,18 @@ package rules
 import (
 	"io/ioutil"
 	"log"
+	"os"
 
 	"github.com/mitchellh/mapstructure"
 	"gopkg.in/yaml.v2"
 )
 
+type MissingRulesFile struct{}
+
+func (e *MissingRulesFile) Error() string {
+	return "Rules file is missing"
+}
+
 type RulesConfig struct {
 	Version int
 	Rules   []Rule
@@ -19,6 +26,9 @@ func LoadRulesConfig(filepath string) (RulesConfig, error) {
 	log.Printf("Loading rules config file %s", filepath)
 	rulesBytes, err := ioutil.ReadFile(filepath)
 	if err != nil {
+		if os.IsNotExist(err) {
+			return RulesConfig{}, &MissingRulesFile{}
+		}
 		return RulesConfig{}, err
 	}