make only specific keys configurable by validating them (#18)

cmd/commands/config/config.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 
 	"github.com/craftamap/bb/cmd/options"
+	"github.com/craftamap/bb/config"
 	bbgit "github.com/craftamap/bb/git"
 	"github.com/craftamap/bb/util/logging"
 	"github.com/kirsle/configdir"
@@ -37,6 +38,16 @@ func Add(rootCmd *cobra.Command, _ *options.GlobalOptions) {
 			if Get {
 				// TODO: code here
 			} else {
+				key := args[0]
+				inputValue := args[1]
+
+				newValue, err := config.BbConfigurationValidation.ValidateEntry(key, inputValue)
+
+				if err != nil {
+					logging.Error(fmt.Sprintf("failed to validate %s: %s", inputValue, err))
+					return
+				}
+
 				var configDirectory string
 				var filename string
 				if Local {
@@ -75,9 +86,6 @@ func Add(rootCmd *cobra.Command, _ *options.GlobalOptions) {
 				tmpVp.SetConfigFile(path)
 				tmpVp.ReadInConfig()
 
-				key := args[0]
-				newValue := args[1]
-
 				isSetAlready := tmpVp.IsSet(key)
 				oldValue := tmpVp.Get(key)
 
@@ -122,7 +130,6 @@ func Add(rootCmd *cobra.Command, _ *options.GlobalOptions) {
 					return
 				}
 
-
 				logging.SuccessExclamation(fmt.Sprintf("Successfully updated configuration %s", path))
 			}
 		},
@@ -137,7 +144,7 @@ func Add(rootCmd *cobra.Command, _ *options.GlobalOptions) {
 func copyFileContent(src string, dst string) error {
 	sourceFileStat, err := os.Stat(src)
 	if err != nil {
-		return  err
+		return err
 	}
 
 	if !sourceFileStat.Mode().IsRegular() {

config/config.go

@@ -0,0 +1,79 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+)
+
+type Validator func(interface{}) (interface{}, error)
+
+// Enum is just a string of a list
+func EnumValidator(validValues ...string) Validator {
+	return func(inputValue interface{}) (interface{}, error) {
+		_, ok := inputValue.(string)
+		if !ok {
+			return "", fmt.Errorf("value \"%s\" is not a string, but of type %T", inputValue, inputValue)
+		}
+		isInList := false
+		for _, validValue := range validValues {
+			if inputValue == validValue {
+				isInList = true
+				break
+			}
+		}
+		if !isInList {
+			return "", fmt.Errorf("value \"%s\" is not a valid value. Valid Values are %s", inputValue, validValues)
+		}
+
+		return inputValue, nil
+	}
+}
+
+// SimpleStringValidator validates if a input is a "simple" string - only single-line strings are supported
+func SimpleStringValidator() Validator {
+	return func(inputValue interface{}) (interface{}, error) {
+		_, ok := inputValue.(string)
+		if !ok {
+			return "", fmt.Errorf("value \"%s\" is not a string, but of type %T", inputValue, inputValue)
+		}
+
+		if strings.ContainsAny(inputValue.(string), "\r\n") {
+			return "", fmt.Errorf("value \"%s\" contains illegal line break", inputValue)
+		}
+
+		return inputValue, nil
+	}
+}
+
+// Entry contains all the data required for Validation and Convertion
+type Entry struct {
+	Validator Validator
+}
+
+type Configuration map[string]Entry
+
+func (c Configuration) ValidateEntry(key string, value interface{}) (interface{}, error) {
+	e, ok := c[key]
+	if !ok {
+		return "", fmt.Errorf("key \"%s\" is not a valid key", key)
+	}
+	return e.Validator(value)
+}
+
+var BbConfigurationValidation Configuration = map[string]Entry{
+	"username": {
+		Validator: SimpleStringValidator(),
+	},
+	"password": {
+		Validator: SimpleStringValidator(),
+	},
+	"remote": {
+		Validator: SimpleStringValidator(),
+	},
+	"git_protocol": {
+		Validator: EnumValidator("ssh", "https"),
+	},
+	"sync-method": {
+		Validator: EnumValidator("merge", "rebase"),
+	},
+}