Pull out the function to read and parse config files and add some more error handling.

config.go

@@ -3,13 +3,40 @@ package main
 import (
 	"errors"
 	"fmt"
-	_ "strconv"
+	"os"
 	"strings"
+
+	"github.com/hjson/hjson-go/v4"
 )
 
-// Configuration errors
+// Errors
 var ErrUndefined = errors.New("value not defined")
+var ErrFileNotFound = errors.New("file not found")
+var ErrParse = errors.New("file could not be parsed")
 
+// File and parsing errors
+type ParseError struct{
+	File	string
+	Err	error
+}
+
+func (e *ParseError) Error() string {
+	return fmt.Sprintf("Error parsing configuration file %s: %s",
+		e.File, e.Err.Error())
+}
+
+func (e *ParseError) Unwrap() error { return e.Err }
+
+func fileNotFoundError(file string) *ParseError {
+	return &ParseError{file, ErrFileNotFound}
+}
+
+func parsingError(file string) *ParseError {
+	return &ParseError{file, ErrParse}
+}
+
+
+// Config struct errors
 type ConfigError struct {
 	Key	string
 	Value	interface{}
@@ -27,6 +54,25 @@ func undefinedError(key string) *ConfigError {
 	return &ConfigError{key, nil, ErrUndefined}
 }
 
+
+func ParseConfig(file string) (Config, error) {
+	var err error
+	var c Config
+
+	fp, err := os.ReadFile(file)
+	if err != nil {
+		return Config{}, fileNotFoundError(file)
+	}
+
+	err = hjson.Unmarshal(fp, &c)
+	if err != nil {
+		fmt.Println(err)
+		return Config{}, parsingError(file)
+	}
+
+	return c, nil
+}
+
 // Get the first host port from a service
 func (s ServiceConfig) GetHostPort() (string, error) {
 	if s.Ports == nil {

main.go

@@ -44,41 +44,21 @@ type ServiceConfig struct {
 }
 
 func main() {
-	var err error
-	var config Config
-
 	// Initialize structs for scripted configurations
 	ScriptedInit()
 
 	// Read user config file
-	{
-		file, err := os.ReadFile("goolinux.json")
-		if err != nil {
-			fmt.Println("Cannot read user config file")
-			fmt.Println(err)
-			return
-		}
-
-		err = hjson.Unmarshal(file, &config)
-		if err != nil {
-			fmt.Println(err)
-			return
-		}
+	config, err := ParseConfig("goolinux.json")
+	if err != nil {
+		fmt.Println(err)
+		return
 	}
 
 	// Read system "base" config file if it exists
 	if config.System.Base != "" {
-		var systemConfig Config
 		fp := "services/" + config.System.Base + ".json"
 
-		file, err := os.ReadFile(fp)
-		if err != nil {
-			fmt.Println("Cannot read system base config file")
-			fmt.Println(err)
-			return
-		}
-
-		err = hjson.Unmarshal(file, &systemConfig)
+		systemConfig, err := ParseConfig(fp)
 		if err != nil {
 			fmt.Println(err)
 			return