Add persistent store and module IDs

Signed-off-by: Knut Ahlers <knut@ahlers.me>

config.go

@@ -13,13 +13,15 @@ import (
 
 type (
 	configFile struct {
-		BotToken string `yaml:"bot_token"`
-		GuildID  string `yaml:"guild_id"`
+		BotToken      string `yaml:"bot_token"`
+		GuildID       string `yaml:"guild_id"`
+		StoreLocation string `yaml:"store_location"`
 
 		ModuleConfigs []moduleConfig `yaml:"module_configs"`
 	}
 
 	moduleConfig struct {
+		ID         string               `yaml:"id"`
 		Type       string               `yaml:"type"`
 		Attributes moduleAttributeStore `yaml:"attributes"`
 	}

main.go

@@ -23,6 +23,7 @@ var (
 	}{}
 
 	config *configFile
+	store  *metaStore
 
 	version = "dev"
 )
@@ -57,6 +58,14 @@ func main() {
 		log.WithError(err).Fatal("Unable to load config file")
 	}
 
+	if config.StoreLocation == "" {
+		log.Fatal("Config contains no store location")
+	}
+
+	if store, err = newMetaStoreFromDisk(config.StoreLocation); err != nil {
+		log.WithError(err).Fatal("Unable to load store")
+	}
+
 	// Connect to Discord
 	if discord, err = discordgo.New(strings.Join([]string{"Bot", config.BotToken}, " ")); err != nil {
 		log.WithError(err).Fatal("Unable to create discord client")
@@ -66,15 +75,22 @@ func main() {
 
 	for i, mc := range config.ModuleConfigs {
 		logger := log.WithFields(log.Fields{
+			"id":     mc.ID,
 			"idx":    i,
 			"module": mc.Type,
 		})
+
+		if mc.ID == "" {
+			logger.Error("Module contains no ID and will be disabled")
+			continue
+		}
+
 		mod := GetModuleByName(mc.Type)
 		if mod == nil {
 			logger.Fatal("Found configuration for unsupported module")
 		}
 
-		if err = mod.Initialize(crontab, discord, mc.Attributes); err != nil {
+		if err = mod.Initialize(mc.ID, crontab, discord, mc.Attributes); err != nil {
 			logger.WithError(err).Fatal("Unable to initialize module")
 		}
 

metastore.go

@@ -0,0 +1,86 @@
+package main
+
+import (
+	"encoding/json"
+	"os"
+	"sync"
+
+	"github.com/pkg/errors"
+)
+
+type metaStore struct {
+	ModuleAttributes map[string]moduleAttributeStore `json:"module_attributes"`
+
+	filename string
+	lock     sync.RWMutex
+}
+
+func newMetaStoreFromDisk(filename string) (*metaStore, error) {
+	out := &metaStore{
+		ModuleAttributes: map[string]moduleAttributeStore{},
+		filename:         filename,
+	}
+
+	f, err := os.Open(filename)
+	switch {
+	case err == nil:
+		// This is fine
+
+	case os.IsNotExist(err):
+		// No store yet, return empty store
+		return out, nil
+
+	default:
+		return nil, errors.Wrap(err, "opening store")
+	}
+	defer f.Close()
+
+	return out, errors.Wrap(
+		json.NewDecoder(f).Decode(out),
+		"decoding store",
+	)
+}
+
+func (m *metaStore) Save() error {
+	m.lock.RLock()
+	defer m.lock.RUnlock()
+
+	return m.save()
+}
+
+func (m *metaStore) save() error {
+	f, err := os.Create(m.filename)
+	if err != nil {
+		return errors.Wrap(err, "creating storage file")
+	}
+	defer f.Close()
+
+	return errors.Wrap(
+		json.NewEncoder(f).Encode(m),
+		"encoding storage file",
+	)
+}
+
+func (m *metaStore) Set(moduleID, key string, value interface{}) error {
+	m.lock.Lock()
+	defer m.lock.Unlock()
+
+	if m.ModuleAttributes[moduleID] == nil {
+		m.ModuleAttributes[moduleID] = make(moduleAttributeStore)
+	}
+
+	m.ModuleAttributes[moduleID][key] = value
+
+	return errors.Wrap(m.save(), "saving store")
+}
+
+func (m *metaStore) ReadWithLock(moduleID string, fn func(m moduleAttributeStore) error) error {
+	m.lock.RLock()
+	defer m.lock.RUnlock()
+
+	if m.ModuleAttributes[moduleID] == nil {
+		return fn(moduleAttributeStore{})
+	}
+
+	return fn(m.ModuleAttributes[moduleID])
+}

mod_clearChannel.go

@@ -28,11 +28,15 @@ func init() {
 type modClearChannel struct {
 	attrs   moduleAttributeStore
 	discord *discordgo.Session
+	id      string
 }
 
-func (m *modClearChannel) Initialize(crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
+func (m modClearChannel) ID() string { return m.id }
+
+func (m *modClearChannel) Initialize(id string, crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
 	m.attrs = attrs
 	m.discord = discord
+	m.id = id
 
 	if err := attrs.Expect(
 		"discord_channel_id",

mod_livePosting.go

@@ -36,11 +36,15 @@ func init() {
 type modLivePosting struct {
 	attrs   moduleAttributeStore
 	discord *discordgo.Session
+	id      string
 }
 
-func (m *modLivePosting) Initialize(crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
+func (m modLivePosting) ID() string { return m.id }
+
+func (m *modLivePosting) Initialize(id string, crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
 	m.attrs = attrs
 	m.discord = discord
+	m.id = id
 
 	if err := attrs.Expect(
 		"discord_channel_id",

mod_liveRole.go

@@ -24,11 +24,15 @@ func init() {
 type modLiveRole struct {
 	attrs   moduleAttributeStore
 	discord *discordgo.Session
+	id      string
 }
 
-func (m *modLiveRole) Initialize(crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
+func (m modLiveRole) ID() string { return m.id }
+
+func (m *modLiveRole) Initialize(id string, crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
 	m.attrs = attrs
 	m.discord = discord
+	m.id = id
 
 	if err := attrs.Expect(
 		"role_streamers_live",

mod_presence.go

@@ -28,11 +28,15 @@ func init() {
 type modPresence struct {
 	attrs   moduleAttributeStore
 	discord *discordgo.Session
+	id      string
 }
 
-func (m *modPresence) Initialize(crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
+func (m modPresence) ID() string { return m.id }
+
+func (m *modPresence) Initialize(id string, crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
 	m.attrs = attrs
 	m.discord = discord
+	m.id = id
 
 	if err := attrs.Expect(
 		"fallback_text",

mod_streamSchedule.go

@@ -34,11 +34,15 @@ func init() {
 type modStreamSchedule struct {
 	attrs   moduleAttributeStore
 	discord *discordgo.Session
+	id      string
 }
 
-func (m *modStreamSchedule) Initialize(crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
+func (m modStreamSchedule) ID() string { return m.id }
+
+func (m *modStreamSchedule) Initialize(id string, crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error {
 	m.attrs = attrs
 	m.discord = discord
+	m.id = id
 
 	if err := attrs.Expect(
 		"discord_channel_id",

modules.go

@@ -15,7 +15,8 @@ var (
 
 type (
 	module interface {
-		Initialize(crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error
+		ID() string
+		Initialize(id string, crontab *cron.Cron, discord *discordgo.Session, attrs moduleAttributeStore) error
 		Setup() error
 	}