Rename the config structs setDefaults to validate

This allows us to check for some required values and give an easy to respond
to error at startup rather than a lot of validation during run time.

config/appservice.go

@@ -13,12 +13,12 @@ type appservice struct {
 	HSToken string `yaml:"hs_token"`
 }
 
-func (a *appservice) setDefaults() error {
+func (a *appservice) validate() error {
 	if a.ID == "" {
 		a.ID = "discord"
 	}
 
-	if err := a.Bot.setDefaults(); err != nil {
+	if err := a.Bot.validate(); err != nil {
 		return err
 	}
 
@@ -35,5 +35,5 @@ func (a *appservice) UnmarshalYAML(unmarshal func(interface{}) error) error {
 
 	*a = appservice(raw)
 
-	return a.setDefaults()
+	return a.validate()
 }

config/bot.go

@@ -6,7 +6,7 @@ type bot struct {
 	Avatar      string `yaml:"avatar"`
 }
 
-func (b *bot) setDefaults() error {
+func (b *bot) validate() error {
 	if b.Username == "" {
 		b.Username = "discordbot"
 	}
@@ -29,5 +29,5 @@ func (b *bot) UnmarshalYAML(unmarshal func(interface{}) error) error {
 
 	*b = bot(raw)
 
-	return b.setDefaults()
+	return b.validate()
 }

config/bridge.go

@@ -1,8 +1,6 @@
 package config
 
 import (
-	"fmt"
-
 	"bytes"
 	"text/template"
 )
@@ -13,7 +11,7 @@ type bridge struct {
 	usernameTemplate *template.Template `yaml:"-"`
 }
 
-func (b *bridge) setDefaults() error {
+func (b *bridge) validate() error {
 	var err error
 
 	if b.UsernameTemplate == "" {
@@ -40,14 +38,12 @@ func (b *bridge) UnmarshalYAML(unmarshal func(interface{}) error) error {
 
 	*b = bridge(raw)
 
-	return b.setDefaults()
+	return b.validate()
 }
 
 func (b bridge) FormatUsername(userid string) string {
 	var buffer bytes.Buffer
 
-	fmt.Printf("bridge: %#v\n", b)
-
 	b.usernameTemplate.Execute(&buffer, userid)
 
 	return buffer.String()

config/config.go

@@ -12,12 +12,16 @@ type Config struct {
 	Bridge     bridge     `yaml:"bridge"`
 }
 
-func (cfg *Config) setDefaults() error {
-	if err := cfg.Appservice.setDefaults(); err != nil {
+func (cfg *Config) validate() error {
+	if err := cfg.Homeserver.validate(); err != nil {
 		return err
 	}
 
-	if err := cfg.Bridge.setDefaults(); err != nil {
+	if err := cfg.Appservice.validate(); err != nil {
+		return err
+	}
+
+	if err := cfg.Bridge.validate(); err != nil {
 		return err
 	}
 
@@ -32,7 +36,7 @@ func (cfg *Config) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		return err
 	}
 
-	return cfg.setDefaults()
+	return cfg.validate()
 }
 
 func FromBytes(data []byte) (*Config, error) {
@@ -42,7 +46,9 @@ func FromBytes(data []byte) (*Config, error) {
 		return nil, err
 	}
 
-	cfg.setDefaults()
+	if err := cfg.validate(); err != nil {
+		return nil, err
+	}
 
 	return &cfg, nil
 }

config/homeserver.go

@@ -1,7 +1,41 @@
 package config
 
+import (
+	"errors"
+)
+
+var (
+	ErrHomeserverNoAddress = errors.New("no homeserver address specified")
+	ErrHomeserverNoDomain  = errors.New("no homeserver domain specified")
+)
+
 type homeserver struct {
 	Address        string `yaml:"address"`
 	Domain         string `yaml:"domain"`
 	StatusEndpoint string `yaml:"status_endpoint"`
 }
+
+func (h *homeserver) validate() error {
+	if h.Address == "" {
+		return ErrHomeserverNoAddress
+	}
+
+	if h.Domain == "" {
+		return ErrHomeserverNoDomain
+	}
+
+	return nil
+}
+
+func (h *homeserver) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type rawHomeserver homeserver
+
+	raw := rawHomeserver{}
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	*h = homeserver(raw)
+
+	return h.validate()
+}