Add a generate-registration command

config/appservice.go

@@ -5,6 +5,10 @@ type appservice struct {
 	Hostname string `yaml:"hostname"`
 	Port     uint16 `yaml:"port"`
 
+	ID string `yaml:"id"`
+
+	Bot bot `yaml:"bot"`
+
 	ASToken string `yaml:"as_token"`
 	HSToken string `yaml:"hs_token"`
 }

config/bot.go

@@ -0,0 +1,7 @@
+package config
+
+type bot struct {
+	Username    string `yaml:"username"`
+	Displayname string `yaml:"displayname"`
+	Avatar      string `yaml:"avatar"`
+}

config/bridge.go

@@ -0,0 +1,40 @@
+package config
+
+import (
+	"bytes"
+	"text/template"
+)
+
+type bridge struct {
+	UsernameTemplate string `yaml:"username_template"`
+
+	usernameTemplate *template.Template `yaml:"-"`
+}
+
+func (b *bridge) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	type rawBridge bridge
+
+	raw := rawBridge{}
+
+	err := unmarshal(&raw)
+	if err != nil {
+		return err
+	}
+
+	raw.usernameTemplate, err = template.New("username").Parse(raw.UsernameTemplate)
+	if err != nil {
+		return err
+	}
+
+	*b = bridge(raw)
+
+	return nil
+}
+
+func (b bridge) FormatUsername(userid string) string {
+	var buffer bytes.Buffer
+
+	b.usernameTemplate.Execute(&buffer, userid)
+
+	return buffer.String()
+}

config/config.go

@@ -9,6 +9,7 @@ import (
 type Config struct {
 	Homeserver homeserver `yaml:"homeserver"`
 	Appservice appservice `yaml:"appservice"`
+	Bridge     bridge     `yaml:"bridge"`
 }
 
 func FromBytes(data []byte) (*Config, error) {
@@ -33,3 +34,12 @@ func FromFile(filename string) (*Config, error) {
 
 	return FromBytes(data)
 }
+
+func (cfg *Config) Save(filename string) error {
+	data, err := yaml.Marshal(cfg)
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(filename, data, 0600)
+}

config/registration.go

@@ -0,0 +1,33 @@
+package config
+
+import (
+	"fmt"
+	"regexp"
+
+	as "maunium.net/go/mautrix/appservice"
+)
+
+func (cfg *Config) CopyToRegistration(registration *as.Registration) error {
+	registration.ID = cfg.Appservice.ID
+	registration.URL = cfg.Appservice.Address
+
+	falseVal := false
+	registration.RateLimited = &falseVal
+
+	registration.SenderLocalpart = cfg.Appservice.Bot.Username
+
+	pattern := fmt.Sprintf(
+		"^@%s:%s$",
+		cfg.Bridge.FormatUsername("[0-9]+"),
+		cfg.Homeserver.Domain,
+	)
+
+	userIDRegex, err := regexp.Compile(pattern)
+	if err != nil {
+		return err
+	}
+
+	registration.Namespaces.RegisterUserIDs(userIDRegex, true)
+
+	return nil
+}