feat(preferences): ✨ add support for setting MQTT preferences via the…

… command-line

internal/cli/configCmd.go

@@ -0,0 +1,57 @@
+// Copyright (c) 2024 Joshua Rich <joshua.rich@gmail.com>
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+package cli
+
+import (
+	"errors"
+	"fmt"
+	"path/filepath"
+
+	"github.com/adrg/xdg"
+
+	"github.com/joshuar/go-hass-agent/internal/preferences"
+)
+
+var ErrMQTTServerRequired = errors.New("mqtt-server not specified")
+
+type ConfigCmd struct {
+	Path       string `kong:"hidden"`
+	MQTTConfig `kong:"help='Set MQTT options.'"`
+}
+
+type MQTTConfig preferences.MQTT
+
+func (r *ConfigCmd) Run(ctx *Context) error {
+	r.Path = filepath.Join(xdg.ConfigHome, ctx.AppID)
+
+	prefs, err := preferences.Load(r.Path)
+	if err != nil {
+		return fmt.Errorf("config: load preferences: %w", err)
+	}
+
+	r.MQTTEnabled = true
+	prefs.MQTT = (*preferences.MQTT)(&r.MQTTConfig)
+
+	err = prefs.Save()
+	if err != nil {
+		return fmt.Errorf("config: save preferences: %w", err)
+	}
+
+	return nil
+}
+
+func (r *MQTTConfig) Validate() error {
+	err := validate.Struct(r)
+	if err != nil {
+		return fmt.Errorf("%w: %s", ErrValidationFailed, parseValidationErrors(err))
+	}
+
+	if r.MQTTServer == "" {
+		return ErrMQTTServerRequired
+	}
+
+	return nil
+}

internal/cli/validate.go

@@ -0,0 +1,45 @@
+// Copyright (c) 2024 Joshua Rich <joshua.rich@gmail.com>
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+package cli
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/go-playground/validator/v10"
+)
+
+var validate *validator.Validate
+
+var ErrValidationFailed = errors.New("validation failed")
+
+func init() {
+	validate = validator.New(validator.WithRequiredStructEnabled())
+}
+
+//nolint:errorlint
+//revive:disable:unhandled-error
+func parseValidationErrors(validation error) string {
+	validationErrs, ok := validation.(validator.ValidationErrors)
+	if !ok {
+		return "internal validation error"
+	}
+
+	var message strings.Builder
+
+	for _, err := range validationErrs {
+		switch err.Tag() {
+		case "required":
+			message.WriteString(err.Field() + " is required")
+		default:
+			message.WriteString(err.Field() + " should match " + err.Tag())
+		}
+
+		message.WriteRune(' ')
+	}
+
+	return message.String()
+}

internal/preferences/prefs.go

@@ -59,11 +59,11 @@ type Preferences struct {
 }
 
 type MQTT struct {
-	MQTTServer      string `toml:"server,omitempty" validate:"omitempty,uri"`
-	MQTTUser        string `toml:"user,omitempty" validate:"omitempty"`
-	MQTTPassword    string `toml:"password,omitempty" validate:"omitempty"`
-	MQTTTopicPrefix string `toml:"topic_prefix,omitempty" validate:"omitempty,ascii"`
-	MQTTEnabled     bool   `toml:"enabled" validate:"boolean"`
+	MQTTServer      string `toml:"server,omitempty" validate:"omitempty,uri" kong:"required,help='MQTT server URI. Required.',placeholder='scheme://some.host:port'"` //nolint:lll
+	MQTTUser        string `toml:"user,omitempty" validate:"omitempty" kong:"optional,help='MQTT username.'"`
+	MQTTPassword    string `toml:"password,omitempty" validate:"omitempty" kong:"optional,help='MQTT password.'"`
+	MQTTTopicPrefix string `toml:"topic_prefix,omitempty" validate:"omitempty,ascii" kong:"optional,help='MQTT topic prefix.'"`
+	MQTTEnabled     bool   `toml:"enabled" validate:"boolean" kong:"-"`
 }
 
 func (p *Preferences) Validate() error {

main.go

@@ -27,6 +27,7 @@ var CLI struct {
 	Profile   cli.ProfileFlags `help:"Enable profiling."`
 	AppID     string           `name:"appid" default:"${defaultAppID}" help:"Specify a custom app id (for debugging)."`
 	LogLevel  string           `name:"log-level" enum:"info,debug,trace" default:"info" help:"Set logging level."`
+	Config    cli.ConfigCmd    `cmd:"" help:"Configure Go Hass Agent."`
 	Register  cli.RegisterCmd  `cmd:"" help:"Register with Home Assistant."`
 	NoLogFile bool             `help:"Don't write to a log file."`
 	Headless  bool             `name:"terminal" help:"Run without a GUI."`