Improve event emitter/subscription abilities

This commit is contained in:
Dane Everitt 2020-01-18 14:04:26 -08:00
parent c6fcd8cabb
commit 99a11f81c3
No known key found for this signature in database
GPG Key ID: EEA66103B3D71F53
8 changed files with 131 additions and 103 deletions

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@ -1,6 +1,10 @@
package server
import "io"
import (
"fmt"
"github.com/mitchellh/colorstring"
"io"
)
type Console struct {
Server *Server
@ -19,3 +23,12 @@ func (c Console) Write(b []byte) (int, error) {
return len(b), nil
}
// Sends output to the server console formatted to appear correctly as being sent
// from Wings.
func (s *Server) PublishConsoleOutputFromDaemon(data string) {
s.Events().Publish(
ConsoleOutputEvent,
colorstring.Color(fmt.Sprintf("[yellow][bold][Pterodactyl Daemon]:[default] %s", data)),
)
}

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@ -37,7 +37,7 @@ func (s *Server) handleServerCrash() error {
if !s.CrashDetection.Enabled {
zap.S().Debugw("server triggered crash detection but handler is disabled for server process", zap.String("server", s.Uuid))
s.SendConsoleOutputFromDaemon("Server detected as crashed; crash detection is disabled for this instance.")
s.PublishConsoleOutputFromDaemon("Server detected as crashed; crash detection is disabled for this instance.")
}
return nil
@ -56,15 +56,15 @@ func (s *Server) handleServerCrash() error {
return nil
}
s.SendConsoleOutputFromDaemon("---------- Detected server process in a crashed state! ----------")
s.SendConsoleOutputFromDaemon(fmt.Sprintf("Exit code: %d", exitCode))
s.SendConsoleOutputFromDaemon(fmt.Sprintf("Out of memory: %t", oomKilled))
s.PublishConsoleOutputFromDaemon("---------- Detected server process in a crashed state! ----------")
s.PublishConsoleOutputFromDaemon(fmt.Sprintf("Exit code: %d", exitCode))
s.PublishConsoleOutputFromDaemon(fmt.Sprintf("Out of memory: %t", oomKilled))
c := s.CrashDetection.lastCrash
// If the last crash time was within the last 60 seconds we do not want to perform
// an automatic reboot of the process. Return an error that can be handled.
if !c.IsZero() && c.Add(time.Second * 60).After(time.Now()) {
s.SendConsoleOutputFromDaemon("Aborting automatic reboot: last crash occurred less than 60 seconds ago.")
s.PublishConsoleOutputFromDaemon("Aborting automatic reboot: last crash occurred less than 60 seconds ago.")
return &crashTooFrequent{}
}

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@ -388,7 +388,7 @@ func (d *DockerEnvironment) FollowConsoleOutput() error {
s := bufio.NewScanner(r)
for s.Scan() {
d.Server.Emit(ConsoleOutputEvent, s.Text())
d.Server.Events().Publish(ConsoleOutputEvent, s.Text())
}
if err := s.Err(); err != nil {
@ -450,7 +450,7 @@ func (d *DockerEnvironment) EnableResourcePolling() error {
}
b, _ := json.Marshal(s.Resources)
s.Emit(StatsEvent, string(b))
s.Events().Publish(StatsEvent, string(b))
}
}(d.Server)

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@ -1,14 +1,9 @@
package server
import (
"fmt"
"github.com/mitchellh/colorstring"
"sync"
)
type EventListeners map[string][]EventListenerFunction
type EventListenerFunction *func(string)
// Defines all of the possible output events for a server.
// noinspection GoNameStartsWithPackageName
const (
@ -19,47 +14,63 @@ const (
StatsEvent = "stats"
)
// Adds an event listener for the server instance.
func (s *Server) AddListener(event string, f EventListenerFunction) {
if s.listeners == nil {
s.listeners = make(map[string][]EventListenerFunction)
type Event struct {
Data string
Topic string
}
type EventBus struct {
subscribers map[string][]chan Event
mu sync.Mutex
}
// Returns the server's emitter instance.
func (s *Server) Events() *EventBus {
if s.emitter == nil {
s.emitter = &EventBus{
subscribers: map[string][]chan Event{},
}
}
if _, ok := s.listeners[event]; ok {
s.listeners[event] = append(s.listeners[event], f)
return s.emitter
}
// Publish data to a given topic.
func (e *EventBus) Publish(topic string, data string) {
e.mu.Lock()
defer e.mu.Unlock()
if ch, ok := e.subscribers[topic]; ok {
go func(data Event, cs []chan Event) {
for _, channel := range cs {
channel <- data
}
}(Event{Data: data, Topic: topic}, ch)
}
}
// Subscribe to an emitter topic using a channel.
func (e *EventBus) Subscribe(topic string, ch chan Event) {
e.mu.Lock()
defer e.mu.Unlock()
if p, ok := e.subscribers[topic]; ok {
e.subscribers[topic] = append(p, ch)
} else {
s.listeners[event] = []EventListenerFunction{f}
e.subscribers[topic] = append([]chan Event{}, ch)
}
}
// Removes the event listener for the server instance.
func (s *Server) RemoveListener(event string, f EventListenerFunction) {
if _, ok := s.listeners[event]; ok {
for i := range s.listeners[event] {
if s.listeners[event][i] == f {
s.listeners[event] = append(s.listeners[event][:i], s.listeners[event][i+1:]...)
break
}
}
}
}
// Unsubscribe a channel from a topic.
func (e *EventBus) Unsubscribe(topic string, ch chan Event) {
e.mu.Lock()
defer e.mu.Unlock()
// Emits an event to all of the active listeners for a server.
func (s *Server) Emit(event string, data string) {
if _, ok := s.listeners[event]; ok {
for _, handler := range s.listeners[event] {
go func(f EventListenerFunction, d string) {
(*f)(d)
}(handler, data)
if _, ok := e.subscribers[topic]; ok {
for i := range e.subscribers[topic] {
if ch == e.subscribers[topic][i] {
e.subscribers[topic] = append(e.subscribers[topic][:i], e.subscribers[topic][i+1:]...)
}
}
}
}
// Sends output to the server console formatted to appear correctly as being sent
// from Wings.
func (s *Server) SendConsoleOutputFromDaemon(data string) {
s.Emit(
ConsoleOutputEvent,
colorstring.Color(fmt.Sprintf("[yellow][bold][Pterodactyl Daemon]:[default] %s", data)),
)
}

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@ -268,7 +268,7 @@ func (ip *InstallationProcess) Execute(installPath string) (string, error) {
}
go func(id string) {
ip.Server.Emit(DaemonMessageEvent, "Starting installation process, this could take a few minutes...")
ip.Server.Events().Publish(DaemonMessageEvent, "Starting installation process, this could take a few minutes...")
if err := ip.StreamOutput(id); err != nil {
zap.S().Errorw(
"error handling streaming output for server install process",
@ -276,7 +276,7 @@ func (ip *InstallationProcess) Execute(installPath string) (string, error) {
zap.Error(err),
)
}
ip.Server.Emit(DaemonMessageEvent, "Installation process completed.")
ip.Server.Events().Publish(DaemonMessageEvent, "Installation process completed.")
}(r.ID)
sChann, eChann := ip.client.ContainerWait(ctx, r.ID, container.WaitConditionNotRunning)
@ -309,7 +309,7 @@ func (ip *InstallationProcess) StreamOutput(id string) error {
s := bufio.NewScanner(reader)
for s.Scan() {
ip.Server.Emit(InstallOutputEvent, s.Text())
ip.Server.Events().Publish(InstallOutputEvent, s.Text())
}
if err := s.Err(); err != nil {

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@ -6,19 +6,24 @@ import (
"strings"
)
// Adds all of the internal event listeners we want to use for a server.
func (s *Server) AddEventListeners() {
s.AddListener(ConsoleOutputEvent, s.onConsoleOutput())
}
consoleChannel := make(chan Event)
s.Events().Subscribe(ConsoleOutputEvent, consoleChannel)
var onConsoleOutputListener func(string)
go func() {
for {
select {
case data := <-consoleChannel:
s.onConsoleOutput(data.Data)
}
}
}()
}
// Custom listener for console output events that will check if the given line
// of output matches one that should mark the server as started or not.
func (s *Server) onConsoleOutput() *func(string) {
if onConsoleOutputListener == nil {
onConsoleOutputListener = func (data string) {
func (s *Server) onConsoleOutput(data string) {
// If the specific line of output is one that would mark the server as started,
// set the server to that state. Only do this if the server is not currently stopped
// or stopping.
@ -38,8 +43,4 @@ func (s *Server) onConsoleOutput() *func(string) {
s.SetState(ProcessStoppingState)
}
}
}
}
return &onConsoleOutputListener
}

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@ -64,8 +64,8 @@ type Server struct {
// certain long operations return faster. For example, FS disk space usage.
Cache *cache.Cache `json:"-" yaml:"-"`
// All of the registered event listeners for this server instance.
listeners EventListeners
// Events emitted by the server instance.
emitter *EventBus
// Defines the process configuration for the server instance. This is dynamically
// fetched from the Pterodactyl Server instance each time the server process is
@ -199,7 +199,6 @@ func LoadDirectory(dir string, cfg *config.SystemConfiguration) error {
// Initializes the default required internal struct components for a Server.
func (s *Server) Init() {
s.listeners = make(map[string][]EventListenerFunction)
s.mutex = &sync.Mutex{}
}
@ -357,7 +356,7 @@ func (s *Server) SetState(state string) error {
zap.S().Debugw("saw server status change event", zap.String("server", s.Uuid), zap.String("status", s.State))
// Emit the event to any listeners that are currently registered.
s.Emit(StatusEvent, s.State)
s.Events().Publish(StatusEvent, s.State)
// If server was in an online state, and is now in an offline state we should handle
// that as a crash event. In that scenario, check the last crash time, and the crash

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@ -164,7 +164,6 @@ func (rt *Router) routeWebsocket(w http.ResponseWriter, r *http.Request, ps http
JWT: nil,
}
// Register all of the event handlers.
events := []string{
server.StatsEvent,
server.StatusEvent,
@ -173,24 +172,29 @@ func (rt *Router) routeWebsocket(w http.ResponseWriter, r *http.Request, ps http
server.DaemonMessageEvent,
}
var eventFuncs = make(map[string]*func(string))
eventChannel := make(chan server.Event)
for _, event := range events {
var e = event
var fn = func(data string) {
s.Events().Subscribe(event, eventChannel)
}
defer func() {
for _, event := range events {
s.Events().Unsubscribe(event, eventChannel)
}
close(eventChannel)
}()
// Listen for different events emitted by the server and respond to them appropriately.
go func() {
for {
select {
case d := <-eventChannel:
handler.SendJson(&WebsocketMessage{
Event: e,
Args: []string{data},
Event: d.Topic,
Args: []string{d.Data},
})
}
eventFuncs[event] = &fn
s.AddListener(event, &fn)
}
// When done with the socket, remove all of the event handlers we had registered.
defer func() {
for event, action := range eventFuncs {
s.RemoveListener(event, action)
}
}()
@ -354,7 +358,7 @@ func (wsh *WebsocketHandler) HandleInbound(m WebsocketMessage) error {
// On every authentication event, send the current server status back
// to the client. :)
wsh.Server.Emit(server.StatusEvent, wsh.Server.State)
wsh.Server.Events().Publish(server.StatusEvent, wsh.Server.State)
wsh.unsafeSendJson(WebsocketMessage{
Event: AuthenticationSuccessEvent,