Minor refactoring (#106)

- `s/Server/OutputRoomEvent/` in `consumers` to accurately reflect what is being consumed.
- `s/set/userIDSet/` in `notifier.go` for clarity.
- Removed lying comments.
This commit is contained in:
Kegsay 2017-05-17 17:29:26 +01:00 committed by GitHub
parent c8c5a40ebd
commit 917c433fd2
3 changed files with 22 additions and 23 deletions

View File

@ -81,12 +81,12 @@ func main() {
if err := n.Load(db); err != nil { if err := n.Load(db); err != nil {
log.Panicf("startup: failed to set up notifier: %s", err) log.Panicf("startup: failed to set up notifier: %s", err)
} }
server, err := consumers.NewServer(cfg, n, db) consumer, err := consumers.NewOutputRoomEvent(cfg, n, db)
if err != nil { if err != nil {
log.Panicf("startup: failed to create sync server: %s", err) log.Panicf("startup: failed to create room server consumer: %s", err)
} }
if err = server.Start(); err != nil { if err = consumer.Start(); err != nil {
log.Panicf("startup: failed to start sync server") log.Panicf("startup: failed to start room server consumer")
} }
log.Info("Starting sync server on ", *bindAddr) log.Info("Starting sync server on ", *bindAddr)

View File

@ -28,15 +28,15 @@ import (
sarama "gopkg.in/Shopify/sarama.v1" sarama "gopkg.in/Shopify/sarama.v1"
) )
// Server contains all the logic for running a sync server // OutputRoomEvent consumes events that originated in the room server.
type Server struct { type OutputRoomEvent struct {
roomServerConsumer *common.ContinualConsumer roomServerConsumer *common.ContinualConsumer
db *storage.SyncServerDatabase db *storage.SyncServerDatabase
notifier *sync.Notifier notifier *sync.Notifier
} }
// NewServer creates a new sync server. Call Start() to begin consuming from room servers. // NewOutputRoomEvent creates a new OutputRoomEvent consumer. Call Start() to begin consuming from room servers.
func NewServer(cfg *config.Sync, n *sync.Notifier, store *storage.SyncServerDatabase) (*Server, error) { func NewOutputRoomEvent(cfg *config.Sync, n *sync.Notifier, store *storage.SyncServerDatabase) (*OutputRoomEvent, error) {
kafkaConsumer, err := sarama.NewConsumer(cfg.KafkaConsumerURIs, nil) kafkaConsumer, err := sarama.NewConsumer(cfg.KafkaConsumerURIs, nil)
if err != nil { if err != nil {
return nil, err return nil, err
@ -47,7 +47,7 @@ func NewServer(cfg *config.Sync, n *sync.Notifier, store *storage.SyncServerData
Consumer: kafkaConsumer, Consumer: kafkaConsumer,
PartitionStore: store, PartitionStore: store,
} }
s := &Server{ s := &OutputRoomEvent{
roomServerConsumer: &consumer, roomServerConsumer: &consumer,
db: store, db: store,
notifier: n, notifier: n,
@ -58,14 +58,14 @@ func NewServer(cfg *config.Sync, n *sync.Notifier, store *storage.SyncServerData
} }
// Start consuming from room servers // Start consuming from room servers
func (s *Server) Start() error { func (s *OutputRoomEvent) Start() error {
return s.roomServerConsumer.Start() return s.roomServerConsumer.Start()
} }
// onMessage is called when the sync server receives a new event from the room server output log. // onMessage is called when the sync server receives a new event from the room server output log.
// It is not safe for this function to be called from multiple goroutines, or else the // It is not safe for this function to be called from multiple goroutines, or else the
// sync stream position may race and be incorrectly calculated. // sync stream position may race and be incorrectly calculated.
func (s *Server) onMessage(msg *sarama.ConsumerMessage) error { func (s *OutputRoomEvent) onMessage(msg *sarama.ConsumerMessage) error {
// Parse out the event JSON // Parse out the event JSON
var output api.OutputRoomEvent var output api.OutputRoomEvent
if err := json.Unmarshal(msg.Value, &output); err != nil { if err := json.Unmarshal(msg.Value, &output); err != nil {

View File

@ -32,11 +32,10 @@ import (
// in missed events. // in missed events.
type Notifier struct { type Notifier struct {
// A map of RoomID => Set<UserID> : Must only be accessed by the OnNewEvent goroutine // A map of RoomID => Set<UserID> : Must only be accessed by the OnNewEvent goroutine
roomIDToJoinedUsers map[string]set roomIDToJoinedUsers map[string]userIDSet
// Protects currPos and userStreams. // Protects currPos and userStreams.
streamLock *sync.Mutex streamLock *sync.Mutex
// The latest sync stream position: guarded by 'currPosMutex' which is RW to allow // The latest sync stream position
// for concurrent reads on /sync requests
currPos types.StreamPosition currPos types.StreamPosition
// A map of user_id => UserStream which can be used to wake a given user's /sync request. // A map of user_id => UserStream which can be used to wake a given user's /sync request.
userStreams map[string]*UserStream userStreams map[string]*UserStream
@ -44,11 +43,11 @@ type Notifier struct {
// NewNotifier creates a new notifier set to the given stream position. // NewNotifier creates a new notifier set to the given stream position.
// In order for this to be of any use, the Notifier needs to be told all rooms and // In order for this to be of any use, the Notifier needs to be told all rooms and
// the joined users within each of them by calling Notifier.LoadFromDatabase(). // the joined users within each of them by calling Notifier.Load(*storage.SyncServerDatabase).
func NewNotifier(pos types.StreamPosition) *Notifier { func NewNotifier(pos types.StreamPosition) *Notifier {
return &Notifier{ return &Notifier{
currPos: pos, currPos: pos,
roomIDToJoinedUsers: make(map[string]set), roomIDToJoinedUsers: make(map[string]userIDSet),
userStreams: make(map[string]*UserStream), userStreams: make(map[string]*UserStream),
streamLock: &sync.Mutex{}, streamLock: &sync.Mutex{},
} }
@ -142,7 +141,7 @@ func (n *Notifier) setUsersJoinedToRooms(roomIDToUserIDs map[string][]string) {
// This is just the bulk form of addJoinedUser // This is just the bulk form of addJoinedUser
for roomID, userIDs := range roomIDToUserIDs { for roomID, userIDs := range roomIDToUserIDs {
if _, ok := n.roomIDToJoinedUsers[roomID]; !ok { if _, ok := n.roomIDToJoinedUsers[roomID]; !ok {
n.roomIDToJoinedUsers[roomID] = make(set) n.roomIDToJoinedUsers[roomID] = make(userIDSet)
} }
for _, userID := range userIDs { for _, userID := range userIDs {
n.roomIDToJoinedUsers[roomID].add(userID) n.roomIDToJoinedUsers[roomID].add(userID)
@ -174,7 +173,7 @@ func (n *Notifier) fetchUserStream(userID string, makeIfNotExists bool) *UserStr
// Not thread-safe: must be called on the OnNewEvent goroutine only // Not thread-safe: must be called on the OnNewEvent goroutine only
func (n *Notifier) addJoinedUser(roomID, userID string) { func (n *Notifier) addJoinedUser(roomID, userID string) {
if _, ok := n.roomIDToJoinedUsers[roomID]; !ok { if _, ok := n.roomIDToJoinedUsers[roomID]; !ok {
n.roomIDToJoinedUsers[roomID] = make(set) n.roomIDToJoinedUsers[roomID] = make(userIDSet)
} }
n.roomIDToJoinedUsers[roomID].add(userID) n.roomIDToJoinedUsers[roomID].add(userID)
} }
@ -182,7 +181,7 @@ func (n *Notifier) addJoinedUser(roomID, userID string) {
// Not thread-safe: must be called on the OnNewEvent goroutine only // Not thread-safe: must be called on the OnNewEvent goroutine only
func (n *Notifier) removeJoinedUser(roomID, userID string) { func (n *Notifier) removeJoinedUser(roomID, userID string) {
if _, ok := n.roomIDToJoinedUsers[roomID]; !ok { if _, ok := n.roomIDToJoinedUsers[roomID]; !ok {
n.roomIDToJoinedUsers[roomID] = make(set) n.roomIDToJoinedUsers[roomID] = make(userIDSet)
} }
n.roomIDToJoinedUsers[roomID].remove(userID) n.roomIDToJoinedUsers[roomID].remove(userID)
} }
@ -196,17 +195,17 @@ func (n *Notifier) joinedUsers(roomID string) (userIDs []string) {
} }
// A string set, mainly existing for improving clarity of structs in this file. // A string set, mainly existing for improving clarity of structs in this file.
type set map[string]bool type userIDSet map[string]bool
func (s set) add(str string) { func (s userIDSet) add(str string) {
s[str] = true s[str] = true
} }
func (s set) remove(str string) { func (s userIDSet) remove(str string) {
delete(s, str) delete(s, str)
} }
func (s set) values() (vals []string) { func (s userIDSet) values() (vals []string) {
for str := range s { for str := range s {
vals = append(vals, str) vals = append(vals, str)
} }