From f3a6ee7a454f43d71ff3e01a0ddab8e9554b70cf Mon Sep 17 00:00:00 2001
From: Dane Everitt <dane@daneeveritt.com>
Date: Mon, 25 Jan 2021 20:28:24 -0800
Subject: [PATCH] re-refactor code

---
 api/server_endpoints.go         |   2 +-
 cmd/root.go                     |  48 +++++---
 config/config.go                |   4 +-
 router/middleware.go            | 136 ++-------------------
 router/middleware/middleware.go |  27 ++++-
 router/router.go                |   5 +-
 router/router_download.go       |  14 +--
 router/router_server.go         |   8 +-
 router/router_server_files.go   |   6 +-
 router/router_server_ws.go      |   5 +-
 router/router_system.go         |   8 +-
 router/router_transfer.go       |  10 +-
 server/collection.go            |  77 ------------
 server/loader.go                | 128 -------------------
 server/manager.go               | 209 ++++++++++++++++++++++++++++----
 server/server.go                | 114 ++++++++++++++++-
 server/state.go                 | 137 ---------------------
 sftp/server.go                  |   8 +-
 18 files changed, 390 insertions(+), 556 deletions(-)
 delete mode 100644 server/collection.go
 delete mode 100644 server/loader.go
 delete mode 100644 server/state.go

diff --git a/api/server_endpoints.go b/api/server_endpoints.go
index acab7ff..946b949 100644
--- a/api/server_endpoints.go
+++ b/api/server_endpoints.go
@@ -55,7 +55,7 @@ type RawServerData struct {
 // be loaded. If so, those requests are spun-up in additional routines and the final resulting
 // slice of all servers will be returned.
 func (r *Request) GetServers() ([]RawServerData, error) {
-	resp, err := r.Get("/servers", Q{"per_page": strconv.Itoa(int(config.Get().RemoteQuery.BootServersPerPage))})
+	resp, err := r.Get("/servers", Q{"per_page": strconv.Itoa(config.Get().RemoteQuery.BootServersPerPage)})
 	if err != nil {
 		return nil, err
 	}
diff --git a/cmd/root.go b/cmd/root.go
index c2c5ec5..a0558d0 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -137,17 +137,15 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 		"gid":      config.Get().System.User.Gid,
 	}).Info("configured system user successfully")
 
-	panelClient := remote.CreateClient(
+	pclient := remote.CreateClient(
 		config.Get().PanelLocation,
 		config.Get().AuthenticationTokenId,
 		config.Get().AuthenticationToken,
 		remote.WithTimeout(time.Second*time.Duration(config.Get().RemoteQuery.Timeout)),
 	)
-	_ = panelClient
 
-	serverManager := server.NewManager(panelClient)
-
-	if err := serverManager.Initialize(int(c.RemoteQuery.BootServersPerPage)); err != nil {
+	manager, err := server.NewManager(cmd.Context(), pclient)
+	if err != nil {
 		log.WithField("error", err).Fatal("failed to load server configurations")
 	}
 
@@ -160,20 +158,38 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 	}
 
 	// Just for some nice log output.
-	for _, s := range serverManager.GetAll() {
-		log.WithField("server", s.Id()).Info("loaded configuration for server")
+	for _, s := range manager.All() {
+		log.WithField("server", s.Id()).Info("finished loading configuration for server")
 	}
 
-	states, err := server.CachedServerStates()
+	states, err := manager.ReadStates()
 	if err != nil {
 		log.WithField("error", err).Error("failed to retrieve locally cached server states from disk, assuming all servers in offline state")
 	}
 
+	ticker := time.NewTicker(time.Minute)
+	// Every minute, write the current server states to the disk to allow for a more
+	// seamless hard-reboot process in which wings will re-sync server states based
+	// on it's last tracked state.
+	go func() {
+		for {
+			select {
+			case <-ticker.C:
+				if err := manager.PersistStates(); err != nil {
+					log.WithField("error", err).Warn("failed to persist server states to disk")
+				}
+			case <-cmd.Context().Done():
+				ticker.Stop()
+				return
+			}
+		}
+	}()
+
 	// Create a new workerpool that limits us to 4 servers being bootstrapped at a time
 	// on Wings. This allows us to ensure the environment exists, write configurations,
 	// and reboot processes without causing a slow-down due to sequential booting.
 	pool := workerpool.New(4)
-	for _, serv := range serverManager.GetAll() {
+	for _, serv := range manager.All() {
 		s := serv
 
 		// For each server we encounter make sure the root data directory exists.
@@ -184,7 +200,6 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 
 		pool.Submit(func() {
 			s.Log().Info("configuring server environment and restoring to previous state")
-
 			var st string
 			if state, exists := states[s.Id()]; exists {
 				st = state
@@ -236,14 +251,14 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 	defer func() {
 		// Cancel the context on all of the running servers at this point, even though the
 		// program is just shutting down.
-		for _, s := range server.GetServers().All() {
+		for _, s := range manager.All() {
 			s.CtxCancel()
 		}
 	}()
 
 	go func() {
 		// Run the SFTP server.
-		if err := sftp.New().Run(); err != nil {
+		if err := sftp.New(manager).Run(); err != nil {
 			log.WithError(err).Fatal("failed to initialize the sftp server")
 			return
 		}
@@ -278,7 +293,7 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 	// and external clients.
 	s := &http.Server{
 		Addr:      api.Host + ":" + strconv.Itoa(api.Port),
-		Handler:   router.Configure(serverManager),
+		Handler:   router.Configure(manager),
 		TLSConfig: config.DefaultTLSConfig,
 	}
 
@@ -323,13 +338,6 @@ func rootCmdRun(cmd *cobra.Command, _ []string) {
 	}
 }
 
-	// Cancel the context on all of the running servers at this point, even though the
-	// program is just shutting down.
-	for _, s := range serverManager.GetAll() {
-		s.CtxCancel()
-	}
-}
-
 // Reads the configuration from the disk and then sets up the global singleton
 // with all of the configuration values.
 func initConfig() {
diff --git a/config/config.go b/config/config.go
index 0a7ec8a..d79dd83 100644
--- a/config/config.go
+++ b/config/config.go
@@ -99,7 +99,7 @@ type RemoteQueryConfiguration struct {
 	// are taking longer than 30 seconds to complete it is likely a performance issue that
 	// should be resolved on the Panel, and not something that should be resolved by upping this
 	// number.
-	Timeout uint `default:"30" yaml:"timeout"`
+	Timeout int `default:"30" yaml:"timeout"`
 
 	// The number of servers to load in a single request to the Panel API when booting the
 	// Wings instance. A single request is initially made to the Panel to get this number
@@ -110,7 +110,7 @@ type RemoteQueryConfiguration struct {
 	// memory limits on your Panel instance. In the grand scheme of things 4 requests for
 	// 50 servers is likely just as quick as two for 100 or one for 400, and will certainly
 	// be less likely to cause performance issues on the Panel.
-	BootServersPerPage uint `default:"50" yaml:"boot_servers_per_page"`
+	BootServersPerPage int `default:"50" yaml:"boot_servers_per_page"`
 }
 
 // SystemConfiguration defines basic system configuration settings.
diff --git a/router/middleware.go b/router/middleware.go
index f2aff64..ee8f18e 100644
--- a/router/middleware.go
+++ b/router/middleware.go
@@ -1,138 +1,16 @@
 package router
 
 import (
-	"io"
-	"net/http"
-	"strings"
-
-	"emperror.dev/errors"
 	"github.com/gin-gonic/gin"
-	"github.com/google/uuid"
-	"github.com/pterodactyl/wings/config"
+	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/server"
 )
 
-type Middleware struct {
-	serverManager server.Manager
-}
-
-// A custom handler function allowing for errors bubbled up by c.Error() to be returned in a
-// standardized format with tracking UUIDs on them for easier log searching.
-func (m *Middleware) ErrorHandler() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		c.Next()
-		err := c.Errors.Last()
-		if err == nil || err.Err == nil {
-			return
-		}
-		tracked := NewTrackedError(err.Err)
-		// If there is a server in the context for this request pull it out so that we can
-		// track the error specifically for that server.
-		if s, ok := c.Get("server"); ok {
-			tracked = NewServerError(err.Err, s.(*server.Server))
-		}
-		// This error occurs if you submit invalid JSON data to an endpoint.
-		if err.Err.Error() == io.EOF.Error() {
-			c.JSON(c.Writer.Status(), gin.H{"error": "A JSON formatted body is required for this endpoint."})
-			return
-		}
-		tracked.Abort(c)
-		return
-	}
-}
-
-// Set the access request control headers on all of the requests.
-func (m *Middleware) SetAccessControlHeaders() gin.HandlerFunc {
-	origins := config.Get().AllowedOrigins
-	location := config.Get().PanelLocation
-	return func(c *gin.Context) {
-		c.Header("Access-Control-Allow-Credentials", "true")
-		c.Header("Access-Control-Allow-Methods", "GET, POST, PATCH, PUT, DELETE, OPTIONS")
-		c.Header("Access-Control-Allow-Headers", "Accept, Accept-Encoding, Authorization, Cache-Control, Content-Type, Content-Length, Origin, X-Real-IP, X-CSRF-Token")
-
-		o := c.GetHeader("Origin")
-		if o != location {
-			for _, origin := range origins {
-				if origin != "*" && o != origin {
-					continue
-				}
-				c.Header("Access-Control-Allow-Origin", origin)
-				c.Next()
-				return
-			}
-		}
-		c.Header("Access-Control-Allow-Origin", location)
-		c.Next()
-	}
-}
-
-// Authenticates the request token against the given permission string, ensuring that
-// if it is a server permission, the token has control over that server. If it is a global
-// token, this will ensure that the request is using a properly signed global token.
-func (m *Middleware) RequireAuthorization() gin.HandlerFunc {
-	token := config.Get().AuthenticationToken
-	return func(c *gin.Context) {
-		auth := strings.SplitN(c.GetHeader("Authorization"), " ", 2)
-		if len(auth) != 2 || auth[0] != "Bearer" {
-			c.Header("WWW-Authenticate", "Bearer")
-			c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{
-				"error": "The required authorization heads were not present in the request.",
-			})
-			return
-		}
-
-		// All requests to Wings must be authorized with the authentication token present in
-		// the Wings configuration file. Remeber, all requests to Wings come from the Panel
-		// backend, or using a signed JWT for temporary authentication.
-		if auth[1] == token {
-			c.Next()
-			return
-		}
-		c.AbortWithStatusJSON(http.StatusForbidden, gin.H{
-			"error": "You are not authorized to access this endpoint.",
-		})
-	}
-}
-
-func (m *Middleware) WithServerManager() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		c.Set("servermanager", m.serverManager)
-	}
-}
-
-func ExtractServerManager(c *gin.Context) server.Manager {
-	if s, ok := c.Get("servermanager"); ok {
-		if srvs, ok := s.(server.Manager); ok {
-			return srvs
-		}
-	}
-	return nil
-}
-
-// Ensure that the requested server exists in this setup. Returns a 404 if we cannot
-// locate it.
-func (m *Middleware) ServerExists() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		u, err := uuid.Parse(c.Param("server"))
-		if err == nil {
-			if s := m.serverManager.Get(u.String()); s != nil {
-				c.Set("server", s)
-				c.Next()
-				return
-			}
-		}
-		c.AbortWithStatusJSON(http.StatusNotFound, gin.H{
-			"error": "The resource you requested does not exist.",
-		})
-	}
-}
-
-// Returns the server instance from the gin context. If there is no server set in the
-// context (e.g. calling from a controller not protected by ServerExists) this function
-// will panic.
+// ExtractServer returns the server instance from the gin context. If there is
+// no server set in the context (e.g. calling from a controller not protected
+// by ServerExists) this function will panic.
+//
+// This function is deprecated. Use middleware.ExtractServer.
 func ExtractServer(c *gin.Context) *server.Server {
-	if s, ok := c.Get("server"); ok {
-		return s.(*server.Server)
-	}
-	panic(errors.New("cannot extract server, missing on gin context"))
+	return middleware.ExtractServer(c)
 }
diff --git a/router/middleware/middleware.go b/router/middleware/middleware.go
index ff61300..745f28e 100644
--- a/router/middleware/middleware.go
+++ b/router/middleware/middleware.go
@@ -159,6 +159,15 @@ func AttachRequestID() gin.HandlerFunc {
 	}
 }
 
+// AttachServerManager attaches the server manager to the request context which
+// allows routes to access the underlying server collection.
+func AttachServerManager(m *server.Manager) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.Set("manager", m)
+		c.Next()
+	}
+}
+
 // CaptureAndAbort aborts the request and attaches the provided error to the gin
 // context so it can be reported properly. If the error is missing a stacktrace
 // at the time it is called the stack will be attached.
@@ -239,9 +248,13 @@ func SetAccessControlHeaders() gin.HandlerFunc {
 // the server ID in the fields list.
 func ServerExists() gin.HandlerFunc {
 	return func(c *gin.Context) {
-		s := server.GetServers().Find(func(s *server.Server) bool {
-			return c.Param("server") == s.Id()
-		})
+		var s *server.Server
+		if c.Param("server") != "" {
+			manager := ExtractManager(c)
+			s = manager.Find(func(s *server.Server) bool {
+				return c.Param("server") == s.Id()
+			})
+		}
 		if s == nil {
 			c.AbortWithStatusJSON(http.StatusNotFound, gin.H{"error": "The requested resource does not exist on this instance."})
 			return
@@ -313,3 +326,11 @@ func ExtractServer(c *gin.Context) *server.Server {
 	}
 	return v.(*server.Server)
 }
+
+// ExtractManager returns the server manager instance set on the request context.
+func ExtractManager(c *gin.Context) *server.Manager {
+	if v, ok := c.Get("manager"); ok {
+		return v.(*server.Manager)
+	}
+	panic("middleware/middleware: cannot extract server manager: not present in context")
+}
diff --git a/router/router.go b/router/router.go
index 00eea02..27c5985 100644
--- a/router/router.go
+++ b/router/router.go
@@ -4,21 +4,22 @@ import (
 	"github.com/apex/log"
 	"github.com/gin-gonic/gin"
 	"github.com/pterodactyl/wings/router/middleware"
+	"github.com/pterodactyl/wings/server"
 )
 
 // Configure configures the routing infrastructure for this daemon instance.
-func Configure() *gin.Engine {
+func Configure(m *server.Manager) *gin.Engine {
 	gin.SetMode("release")
 
 	router := gin.New()
 	router.Use(gin.Recovery())
 	router.Use(middleware.AttachRequestID(), middleware.CaptureErrors(), middleware.SetAccessControlHeaders())
+	router.Use(middleware.AttachServerManager(m))
 	// @todo log this into a different file so you can setup IP blocking for abusive requests and such.
 	// This should still dump requests in debug mode since it does help with understanding the request
 	// lifecycle and quickly seeing what was called leading to the logs. However, it isn't feasible to mix
 	// this output in production and still get meaningful logs from it since they'll likely just be a huge
 	// spamfest.
-	router.Use()
 	router.Use(gin.LoggerWithFormatter(func(params gin.LogFormatterParams) string {
 		log.WithFields(log.Fields{
 			"client_ip":  params.ClientIP,
diff --git a/router/router_download.go b/router/router_download.go
index 325ce6e..d72cc48 100644
--- a/router/router_download.go
+++ b/router/router_download.go
@@ -8,13 +8,14 @@ import (
 	"strconv"
 
 	"github.com/gin-gonic/gin"
+	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/router/tokens"
 	"github.com/pterodactyl/wings/server/backup"
 )
 
 // Handle a download request for a server backup.
 func getDownloadBackup(c *gin.Context) {
-	serverManager := ExtractServerManager(c)
+	manager := middleware.ExtractManager(c)
 
 	token := tokens.BackupPayload{}
 	if err := tokens.ParseToken([]byte(c.Query("token")), &token); err != nil {
@@ -22,8 +23,8 @@ func getDownloadBackup(c *gin.Context) {
 		return
 	}
 
-	s := serverManager.Get(token.ServerUuid)
-	if s == nil || !token.IsUniqueRequest() {
+	s, ok := manager.Get(token.ServerUuid)
+	if !ok || !token.IsUniqueRequest() {
 		c.AbortWithStatusJSON(http.StatusNotFound, gin.H{
 			"error": "The requested resource was not found on this server.",
 		})
@@ -59,16 +60,15 @@ func getDownloadBackup(c *gin.Context) {
 
 // Handles downloading a specific file for a server.
 func getDownloadFile(c *gin.Context) {
-	serverManager := ExtractServerManager(c)
-
+	manager := middleware.ExtractManager(c)
 	token := tokens.FilePayload{}
 	if err := tokens.ParseToken([]byte(c.Query("token")), &token); err != nil {
 		NewTrackedError(err).Abort(c)
 		return
 	}
 
-	s := serverManager.Get(token.ServerUuid)
-	if s == nil || !token.IsUniqueRequest() {
+	s, ok := manager.Get(token.ServerUuid)
+	if !ok || !token.IsUniqueRequest() {
 		c.AbortWithStatusJSON(http.StatusNotFound, gin.H{
 			"error": "The requested resource was not found on this server.",
 		})
diff --git a/router/router_server.go b/router/router_server.go
index 8b5ff82..265d642 100644
--- a/router/router_server.go
+++ b/router/router_server.go
@@ -11,6 +11,7 @@ import (
 	"github.com/apex/log"
 	"github.com/gin-gonic/gin"
 	"github.com/pterodactyl/wings/router/downloader"
+	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/router/tokens"
 	"github.com/pterodactyl/wings/server"
 )
@@ -190,8 +191,7 @@ func postServerReinstall(c *gin.Context) {
 
 // Deletes a server from the wings daemon and dissociate it's objects.
 func deleteServer(c *gin.Context) {
-	s := ExtractServer(c)
-	sm := ExtractServerManager(c)
+	s := middleware.ExtractServer(c)
 
 	// Immediately suspend the server to prevent a user from attempting
 	// to start it while this process is running.
@@ -235,7 +235,9 @@ func deleteServer(c *gin.Context) {
 		}
 	}(s.Filesystem().Path())
 
-	sm.Remove(s)
+	middleware.ExtractManager(c).Remove(func(server *server.Server) bool {
+		return server.Id() == s.Id()
+	})
 
 	// Deallocate the reference to this server.
 	s = nil
diff --git a/router/router_server_files.go b/router/router_server_files.go
index 8e372b0..cddcb96 100644
--- a/router/router_server_files.go
+++ b/router/router_server_files.go
@@ -487,7 +487,7 @@ func postServerChmodFile(c *gin.Context) {
 }
 
 func postServerUploadFiles(c *gin.Context) {
-	serverManager := ExtractServerManager(c)
+	manager := middleware.ExtractManager(c)
 
 	token := tokens.UploadPayload{}
 	if err := tokens.ParseToken([]byte(c.Query("token")), &token); err != nil {
@@ -495,8 +495,8 @@ func postServerUploadFiles(c *gin.Context) {
 		return
 	}
 
-	s := serverManager.Get(token.ServerUuid)
-	if s == nil || !token.IsUniqueRequest() {
+	s, ok := manager.Get(token.ServerUuid)
+	if !ok || !token.IsUniqueRequest() {
 		c.AbortWithStatusJSON(http.StatusNotFound, gin.H{
 			"error": "The requested resource was not found on this server.",
 		})
diff --git a/router/router_server_ws.go b/router/router_server_ws.go
index c65a366..eab309d 100644
--- a/router/router_server_ws.go
+++ b/router/router_server_ws.go
@@ -7,13 +7,14 @@ import (
 
 	"github.com/gin-gonic/gin"
 	ws "github.com/gorilla/websocket"
+	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/router/websocket"
 )
 
 // Upgrades a connection to a websocket and passes events along between.
 func getServerWebsocket(c *gin.Context) {
-	serverManager := ExtractServerManager(c)
-	s := serverManager.Get(c.Param("server"))
+	manager := middleware.ExtractManager(c)
+	s, _ := manager.Get(c.Param("server"))
 	handler, err := websocket.GetHandler(s, c.Writer, c.Request)
 	if err != nil {
 		NewServerError(err, s).Abort(c)
diff --git a/router/router_system.go b/router/router_system.go
index 279a3a8..166e8b6 100644
--- a/router/router_system.go
+++ b/router/router_system.go
@@ -9,6 +9,7 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/pterodactyl/wings/config"
 	"github.com/pterodactyl/wings/installer"
+	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/system"
 )
 
@@ -27,8 +28,7 @@ func getSystemInformation(c *gin.Context) {
 // Returns all of the servers that are registered and configured correctly on
 // this wings instance.
 func getAllServers(c *gin.Context) {
-	serverManager := ExtractServerManager(c)
-	c.JSON(http.StatusOK, serverManager.GetAll())
+	c.JSON(http.StatusOK, middleware.ExtractManager(c).All())
 }
 
 // Creates a new server on the wings daemon and begins the installation process
@@ -52,8 +52,8 @@ func postCreateServer(c *gin.Context) {
 
 	// Plop that server instance onto the request so that it can be referenced in
 	// requests from here-on out.
-	serverManager := ExtractServerManager(c)
-	serverManager.Add(install.Server())
+	manager := middleware.ExtractManager(c)
+	manager.Add(install.Server())
 
 	// Begin the installation process in the background to not block the request
 	// cycle. If there are any errors they will be logged and communicated back
diff --git a/router/router_transfer.go b/router/router_transfer.go
index e413de6..1a4d987 100644
--- a/router/router_transfer.go
+++ b/router/router_transfer.go
@@ -25,6 +25,7 @@ import (
 	"github.com/pterodactyl/wings/api"
 	"github.com/pterodactyl/wings/config"
 	"github.com/pterodactyl/wings/installer"
+	"github.com/pterodactyl/wings/router/middleware"
 	"github.com/pterodactyl/wings/router/tokens"
 	"github.com/pterodactyl/wings/server"
 	"github.com/pterodactyl/wings/system"
@@ -323,19 +324,20 @@ func postTransfer(c *gin.Context) {
 			i.Server().Events().Publish(server.TransferLogsEvent, output)
 		}
 
-		serverManager := ExtractServerManager(c)
-
+		manager := middleware.ExtractManager(c)
 		// Mark the server as transferring to prevent problems later on during the process and
 		// then push the server into the global server collection for this instance.
 		i.Server().SetTransferring(true)
-		serverManager.Add(i.Server())
+		manager.Add(i.Server())
 		defer func(s *server.Server) {
 			// In the event that this transfer call fails, remove the server from the global
 			// server tracking so that we don't have a dangling instance.
 			if err := data.sendTransferStatus(!hasError); hasError || err != nil {
 				sendTransferLog("Server transfer failed, check Wings logs for additional information.")
 				s.Events().Publish(server.TransferStatusEvent, "failure")
-				serverManager.Remove(s)
+				manager.Remove(func(match *server.Server) bool {
+					return match.Id() == s.Id()
+				})
 
 				// If the transfer status was successful but the request failed, act like the transfer failed.
 				if !hasError && err != nil {
diff --git a/server/collection.go b/server/collection.go
deleted file mode 100644
index 5b7e46d..0000000
--- a/server/collection.go
+++ /dev/null
@@ -1,77 +0,0 @@
-package server
-
-import "sync"
-
-type Collection struct {
-	items []*Server
-	sync.RWMutex
-}
-
-// Create a new collection from a slice of servers.
-func NewCollection(servers []*Server) *Collection {
-	return &Collection{
-		items: servers,
-	}
-}
-
-// Return all of the items in the collection.
-func (c *Collection) All() []*Server {
-	c.RLock()
-	defer c.RUnlock()
-
-	return c.items
-}
-
-// Adds an item to the collection store.
-func (c *Collection) Add(s *Server) {
-	c.Lock()
-	c.items = append(c.items, s)
-	c.Unlock()
-}
-
-// Returns only those items matching the filter criteria.
-func (c *Collection) Filter(filter func(*Server) bool) []*Server {
-	c.RLock()
-	defer c.RUnlock()
-
-	r := make([]*Server, 0)
-	for _, v := range c.items {
-		if filter(v) {
-			r = append(r, v)
-		}
-	}
-
-	return r
-}
-
-// Returns a single element from the collection matching the filter. If nothing is
-// found a nil result is returned.
-func (c *Collection) Find(filter func(*Server) bool) *Server {
-	c.RLock()
-	defer c.RUnlock()
-
-	for _, v := range c.items {
-		if filter(v) {
-			return v
-		}
-	}
-
-	return nil
-}
-
-// Removes all items from the collection that match the filter function.
-//
-// TODO: cancel the context?
-func (c *Collection) Remove(filter func(*Server) bool) {
-	c.Lock()
-	defer c.Unlock()
-
-	r := make([]*Server, 0)
-	for _, v := range c.items {
-		if !filter(v) {
-			r = append(r, v)
-		}
-	}
-
-	c.items = r
-}
diff --git a/server/loader.go b/server/loader.go
deleted file mode 100644
index 1a74e39..0000000
--- a/server/loader.go
+++ /dev/null
@@ -1,128 +0,0 @@
-package server
-
-import (
-	"context"
-	"encoding/json"
-	"fmt"
-	"os"
-	"path/filepath"
-	"runtime"
-	"time"
-
-	"emperror.dev/errors"
-	"github.com/apex/log"
-	"github.com/gammazero/workerpool"
-	"github.com/pterodactyl/wings/api"
-	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/environment"
-	"github.com/pterodactyl/wings/environment/docker"
-	"github.com/pterodactyl/wings/remote"
-	"github.com/pterodactyl/wings/server/filesystem"
-)
-
-// Iterates over a given directory and loads all of the servers listed before returning
-// them to the calling function.
-func (m *manager) Initialize(serversPerPage int) error {
-	if len(m.servers.items) != 0 {
-		return errors.New("cannot call LoadDirectory with a non-nil collection")
-	}
-
-	log.Info("fetching list of servers from API")
-	assignedServers, err := m.panelClient.GetServers(context.TODO(), serversPerPage)
-	if err != nil {
-		if !remote.IsRequestError(err) {
-			return err
-		}
-
-		return errors.New(err.Error())
-	}
-
-	start := time.Now()
-	log.WithField("total_configs", len(assignedServers)).Info("processing servers returned by the API")
-
-	pool := workerpool.New(runtime.NumCPU())
-	log.Debugf("using %d workerpools to instantiate server instances", runtime.NumCPU())
-	for _, data := range assignedServers {
-		pool.Submit(func() {
-			// Parse the json.RawMessage into an expected struct value. We do this here so that a single broken
-			// server does not cause the entire boot process to hang, and allows us to show more useful error
-			// messaging in the output.
-			d := api.ServerConfigurationResponse{
-				Settings: data.Settings,
-			}
-
-			log.WithField("server", data.Uuid).Info("creating new server object from API response")
-			if err := json.Unmarshal(data.ProcessConfiguration, &d.ProcessConfiguration); err != nil {
-				log.WithField("server", data.Uuid).WithField("error", err).Error("failed to parse server configuration from API response, skipping...")
-				return
-			}
-
-			s, err := FromConfiguration(d)
-			if err != nil {
-				log.WithField("server", data.Uuid).WithField("error", err).Error("failed to load server, skipping...")
-				return
-			}
-
-			m.Add(s)
-		})
-	}
-
-	// Wait until we've processed all of the configuration files in the directory
-	// before continuing.
-	pool.StopWait()
-
-	diff := time.Now().Sub(start)
-	log.WithField("duration", fmt.Sprintf("%s", diff)).Info("finished processing server configurations")
-
-	return nil
-}
-
-// Initializes a server using a data byte array. This will be marshaled into the
-// given struct using a YAML marshaler. This will also configure the given environment
-// for a server.
-func FromConfiguration(data api.ServerConfigurationResponse) (*Server, error) {
-	s, err := New()
-	if err != nil {
-		return nil, errors.WithMessage(err, "loader: failed to instantiate empty server struct")
-	}
-	if err := s.UpdateDataStructure(data.Settings); err != nil {
-		return nil, err
-	}
-
-	s.Archiver = Archiver{Server: s}
-	s.fs = filesystem.New(filepath.Join(config.Get().System.Data, s.Id()), s.DiskSpace(), s.Config().Egg.FileDenylist)
-
-	// Right now we only support a Docker based environment, so I'm going to hard code
-	// this logic in. When we're ready to support other environment we'll need to make
-	// some modifications here obviously.
-	settings := environment.Settings{
-		Mounts:      s.Mounts(),
-		Allocations: s.cfg.Allocations,
-		Limits:      s.cfg.Build,
-	}
-
-	envCfg := environment.NewConfiguration(settings, s.GetEnvironmentVariables())
-	meta := docker.Metadata{
-		Image: s.Config().Container.Image,
-	}
-
-	if env, err := docker.New(s.Id(), &meta, envCfg); err != nil {
-		return nil, err
-	} else {
-		s.Environment = env
-		s.StartEventListeners()
-		s.Throttler().StartTimer(s.Context())
-	}
-
-	// Forces the configuration to be synced with the panel.
-	if err := s.SyncWithConfiguration(data); err != nil {
-		return nil, err
-	}
-
-	// If the server's data directory exists, force disk usage calculation.
-	if _, err := os.Stat(s.Filesystem().Path()); err == nil {
-		s.Filesystem().HasSpaceAvailable(true)
-	}
-
-	return s, nil
-}
diff --git a/server/manager.go b/server/manager.go
index 2ab36cb..4f92762 100644
--- a/server/manager.go
+++ b/server/manager.go
@@ -1,46 +1,203 @@
 package server
 
 import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"runtime"
+	"sync"
+	"time"
+
+	"emperror.dev/errors"
+	"github.com/apex/log"
+	"github.com/gammazero/workerpool"
+	"github.com/pterodactyl/wings/api"
+	"github.com/pterodactyl/wings/config"
 	"github.com/pterodactyl/wings/remote"
 )
 
-type Manager interface {
-	// Initialize fetches all servers assigned to this node from the API.
-	Initialize(serversPerPage int) error
-	GetAll() []*Server
-	Get(uuid string) *Server
-	Add(s *Server)
-	Remove(s *Server)
+type Manager struct {
+	mu      sync.RWMutex
+	servers []*Server
 }
 
-type manager struct {
-	servers Collection
-
-	panelClient remote.Client
+// NewManager returns a new server manager instance. This will boot up all of
+// the servers that are currently present on the filesystem and set them into
+// the manager.
+func NewManager(ctx context.Context, client remote.Client) (*Manager, error) {
+	c := NewEmptyManager()
+	if err := c.initializeFromRemoteSource(ctx, client); err != nil {
+		return nil, err
+	}
+	return c, nil
 }
 
-// NewManager creates a new server manager.
-func NewManager(panelClient remote.Client) Manager {
-	return &manager{panelClient: panelClient}
+// NewEmptyManager returns a new empty manager collection without actually
+// loading any of the servers from the disk. This allows the caller to set their
+// own servers into the collection as needed.
+func NewEmptyManager() *Manager {
+	return &Manager{}
 }
 
-func (m *manager) GetAll() []*Server {
-	return m.servers.items
+// initializeFromRemoteSource iterates over a given directory and loads all of
+// the servers listed before returning them to the calling function.
+func (m *Manager) initializeFromRemoteSource(ctx context.Context, client remote.Client) error {
+	log.Info("fetching list of servers from API")
+	servers, err := client.GetServers(ctx, config.Get().RemoteQuery.BootServersPerPage)
+	if err != nil {
+		if !remote.IsRequestError(err) {
+			return errors.WithStackIf(err)
+		}
+		return errors.New(err.Error())
+	}
+
+	start := time.Now()
+	log.WithField("total_configs", len(servers)).Info("processing servers returned by the API")
+
+	pool := workerpool.New(runtime.NumCPU())
+	log.Debugf("using %d workerpools to instantiate server instances", runtime.NumCPU())
+	for _, data := range servers {
+		pool.Submit(func() {
+			// Parse the json.RawMessage into an expected struct value. We do this here so that a single broken
+			// server does not cause the entire boot process to hang, and allows us to show more useful error
+			// messaging in the output.
+			d := api.ServerConfigurationResponse{
+				Settings: data.Settings,
+			}
+			log.WithField("server", data.Uuid).Info("creating new server object from API response")
+			if err := json.Unmarshal(data.ProcessConfiguration, &d.ProcessConfiguration); err != nil {
+				log.WithField("server", data.Uuid).WithField("error", err).Error("failed to parse server configuration from API response, skipping...")
+				return
+			}
+			s, err := FromConfiguration(d)
+			if err != nil {
+				log.WithField("server", data.Uuid).WithField("error", err).Error("failed to load server, skipping...")
+				return
+			}
+			m.Add(s)
+		})
+	}
+
+	// Wait until we've processed all of the configuration files in the directory
+	// before continuing.
+	pool.StopWait()
+
+	diff := time.Now().Sub(start)
+	log.WithField("duration", fmt.Sprintf("%s", diff)).Info("finished processing server configurations")
+
+	return nil
 }
 
-func (m *manager) Get(uuid string) *Server {
-	return m.servers.Find(func(s *Server) bool {
-		return s.Id() == uuid
+// Put replaces all of the current values in the collection with the value that
+// is passed through.
+func (m *Manager) Put(s []*Server) {
+	m.mu.Lock()
+	m.servers = s
+	m.mu.Unlock()
+}
+
+// All returns all of the items in the collection.
+func (m *Manager) All() []*Server {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+	return m.servers
+}
+
+// Add adds an item to the collection store.
+func (m *Manager) Add(s *Server) {
+	m.mu.Lock()
+	m.servers = append(m.servers, s)
+	m.mu.Unlock()
+}
+
+// Get returns a single server instance and a boolean value indicating if it was
+// found in the global collection or not.
+func (m *Manager) Get(uuid string) (*Server, bool) {
+	match := m.Find(func(server *Server) bool {
+		return server.Id() == uuid
 	})
+	return match, match != nil
 }
 
-func (m *manager) Add(s *Server) {
-	s.manager = m
-	m.servers.Add(s)
+// Filter returns only those items matching the filter criteria.
+func (m *Manager) Filter(filter func(match *Server) bool) []*Server {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+	r := make([]*Server, 0)
+	for _, v := range m.servers {
+		if filter(v) {
+			r = append(r, v)
+		}
+	}
+	return r
 }
 
-func (m *manager) Remove(s *Server) {
-	m.servers.Remove(func(sf *Server) bool {
-		return sf.Id() == s.Id()
-	})
+// Find returns a single element from the collection matching the filter. If
+// nothing is found a nil result is returned.
+func (m *Manager) Find(filter func(match *Server) bool) *Server {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+	for _, v := range m.servers {
+		if filter(v) {
+			return v
+		}
+	}
+	return nil
 }
+
+// Remove removes all items from the collection that match the filter function.
+func (m *Manager) Remove(filter func(match *Server) bool) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	r := make([]*Server, 0)
+	for _, v := range m.servers {
+		if !filter(v) {
+			r = append(r, v)
+		}
+	}
+	m.servers = r
+}
+
+// PersistStates writes the current environment states to the disk for each
+// server. This is generally called at a specific interval defined in the root
+// runner command to avoid hammering disk I/O when tons of server switch states
+// at once. It is fine if this file falls slightly out of sync, it is just here
+// to make recovering from an unexpected system reboot a little easier.
+func (m *Manager) PersistStates() error {
+	states := map[string]string{}
+	for _, s := range m.All() {
+		states[s.Id()] = s.Environment.State()
+	}
+	data, err := json.Marshal(states)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+	if err := ioutil.WriteFile(config.Get().System.GetStatesPath(), data, 0644); err != nil {
+		return errors.WithStack(err)
+	}
+	return nil
+}
+
+// ReadStates returns the state of the servers.
+func (m *Manager) ReadStates() (map[string]string, error) {
+	f, err := os.OpenFile(config.Get().System.GetStatesPath(), os.O_RDONLY|os.O_CREATE, 0644)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+	defer f.Close()
+	var states map[string]string
+	if err := json.NewDecoder(f).Decode(&states); err != nil && err != io.EOF {
+		return nil, errors.WithStack(err)
+	}
+	out := make(map[string]string, 0)
+	// Only return states for servers that we're currently tracking in the system.
+	for id, state := range states {
+		if _, ok := m.Get(id); ok {
+			out[id] = state
+		}
+	}
+	return out, nil
+}
\ No newline at end of file
diff --git a/server/server.go b/server/server.go
index 96773e3..6f2a607 100644
--- a/server/server.go
+++ b/server/server.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"path/filepath"
 	"strings"
 	"sync"
 
@@ -20,7 +21,8 @@ import (
 	"golang.org/x/sync/semaphore"
 )
 
-// High level definition for a server instance being controlled by Wings.
+// Server is the high level definition for a server instance being controlled
+// by Wings.
 type Server struct {
 	// Internal mutex used to block actions that need to occur sequentially, such as
 	// writing the configuration to the disk.
@@ -28,9 +30,6 @@ type Server struct {
 	ctx       context.Context
 	ctxCancel *context.CancelFunc
 
-	// manager holds a reference to the manager responsible for the server
-	manager *manager
-
 	emitterLock  sync.Mutex
 	powerLock    *semaphore.Weighted
 	throttleOnce sync.Once
@@ -248,4 +247,109 @@ func (s *Server) EnsureDataDirectoryExists() error {
 		}
 	}
 	return nil
-}
\ No newline at end of file
+}
+
+// Sets the state of the server internally. This function handles crash detection as
+// well as reporting to event listeners for the server.
+func (s *Server) OnStateChange() {
+	prevState := s.resources.State.Load()
+
+	st := s.Environment.State()
+	// Update the currently tracked state for the server.
+	s.resources.State.Store(st)
+
+	// Emit the event to any listeners that are currently registered.
+	if prevState != s.Environment.State() {
+		s.Log().WithField("status", st).Debug("saw server status change event")
+		s.Events().Publish(StatusEvent, st)
+	}
+
+	// Reset the resource usage to 0 when the process fully stops so that all of the UI
+	// views in the Panel correctly display 0.
+	if st == environment.ProcessOfflineState {
+		s.resources.Reset()
+		s.emitProcUsage()
+	}
+
+	// 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
+	// counter.
+	//
+	// In the event that we have passed the thresholds, don't do anything, otherwise
+	// automatically attempt to start the process back up for the user. This is done in a
+	// separate thread as to not block any actions currently taking place in the flow
+	// that called this function.
+	if (prevState == environment.ProcessStartingState || prevState == environment.ProcessRunningState) && s.Environment.State() == environment.ProcessOfflineState {
+		s.Log().Info("detected server as entering a crashed state; running crash handler")
+
+		go func(server *Server) {
+			if err := server.handleServerCrash(); err != nil {
+				if IsTooFrequentCrashError(err) {
+					server.Log().Info("did not restart server after crash; occurred too soon after the last")
+				} else {
+					s.PublishConsoleOutputFromDaemon("Server crash was detected but an error occurred while handling it.")
+					server.Log().WithField("error", err).Error("failed to handle server crash")
+				}
+			}
+		}(s)
+	}
+}
+
+// Determines if the server state is running or not. This is different than the
+// environment state, it is simply the tracked state from this daemon instance, and
+// not the response from Docker.
+func (s *Server) IsRunning() bool {
+	st := s.Environment.State()
+
+	return st == environment.ProcessRunningState || st == environment.ProcessStartingState
+}
+
+// FromConfiguration initializes a server using a data byte array. This will be
+// marshaled into the given struct using a YAML marshaler. This will also
+// configure the given environment for a server.
+func FromConfiguration(data api.ServerConfigurationResponse) (*Server, error) {
+	s, err := New()
+	if err != nil {
+		return nil, errors.WithMessage(err, "loader: failed to instantiate empty server struct")
+	}
+	if err := s.UpdateDataStructure(data.Settings); err != nil {
+		return nil, err
+	}
+
+	s.Archiver = Archiver{Server: s}
+	s.fs = filesystem.New(filepath.Join(config.Get().System.Data, s.Id()), s.DiskSpace(), s.Config().Egg.FileDenylist)
+
+	// Right now we only support a Docker based environment, so I'm going to hard code
+	// this logic in. When we're ready to support other environment we'll need to make
+	// some modifications here obviously.
+	settings := environment.Settings{
+		Mounts:      s.Mounts(),
+		Allocations: s.cfg.Allocations,
+		Limits:      s.cfg.Build,
+	}
+
+	envCfg := environment.NewConfiguration(settings, s.GetEnvironmentVariables())
+	meta := docker.Metadata{
+		Image: s.Config().Container.Image,
+	}
+
+	if env, err := docker.New(s.Id(), &meta, envCfg); err != nil {
+		return nil, err
+	} else {
+		s.Environment = env
+		s.StartEventListeners()
+		s.Throttler().StartTimer(s.Context())
+	}
+
+	// Forces the configuration to be synced with the panel.
+	if err := s.SyncWithConfiguration(data); err != nil {
+		return nil, err
+	}
+
+	// If the server's data directory exists, force disk usage calculation.
+	if _, err := os.Stat(s.Filesystem().Path()); err == nil {
+		s.Filesystem().HasSpaceAvailable(true)
+	}
+
+	return s, nil
+}
diff --git a/server/state.go b/server/state.go
deleted file mode 100644
index 3e4378a..0000000
--- a/server/state.go
+++ /dev/null
@@ -1,137 +0,0 @@
-package server
-
-import (
-	"encoding/json"
-	"io"
-	"io/ioutil"
-	"os"
-	"sync"
-
-	"github.com/pterodactyl/wings/config"
-	"github.com/pterodactyl/wings/environment"
-)
-
-var stateMutex sync.Mutex
-
-// Returns the state of the servers.
-func CachedServerStates() (map[string]string, error) {
-	// Request a lock after we check if the file exists.
-	stateMutex.Lock()
-	defer stateMutex.Unlock()
-
-	// Open the states file.
-	f, err := os.OpenFile(config.Get().System.GetStatesPath(), os.O_RDONLY|os.O_CREATE, 0644)
-	if err != nil {
-		return nil, err
-	}
-	defer f.Close()
-
-	// Convert the json object to a map.
-	states := map[string]string{}
-	if err := json.NewDecoder(f).Decode(&states); err != nil && err != io.EOF {
-		return nil, err
-	}
-
-	return states, nil
-}
-
-// saveServerStates .
-func (m *manager) saveServerStates() error {
-	// Get the states of all servers on the daemon.
-	states := map[string]string{}
-	for _, s := range m.GetAll() {
-		states[s.Id()] = s.Environment.State()
-	}
-
-	// Convert the map to a json object.
-	data, err := json.Marshal(states)
-	if err != nil {
-		return err
-	}
-
-	stateMutex.Lock()
-	defer stateMutex.Unlock()
-
-	// Write the data to the file
-	if err := ioutil.WriteFile(config.Get().System.GetStatesPath(), data, 0644); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// Sets the state of the server internally. This function handles crash detection as
-// well as reporting to event listeners for the server.
-func (s *Server) OnStateChange() {
-	prevState := s.resources.State.Load()
-
-	st := s.Environment.State()
-	// Update the currently tracked state for the server.
-	s.resources.State.Store(st)
-
-	// Emit the event to any listeners that are currently registered.
-	if prevState != s.Environment.State() {
-		s.Log().WithField("status", st).Debug("saw server status change event")
-		s.Events().Publish(StatusEvent, st)
-	}
-
-	// Persist this change to the disk immediately so that should the Daemon be stopped or
-	// crash we can immediately restore the server state.
-	//
-	// This really only makes a difference if all of the Docker containers are also stopped,
-	// but this was a highly requested feature and isn't hard to work with, so lets do it.
-	//
-	// We also get the benefit of server status changes always propagating corrected configurations
-	// to the disk should we forget to do it elsewhere.
-	go func() {
-		if err := s.manager.saveServerStates(); err != nil {
-			s.Log().WithField("error", err).Warn("failed to write server states to disk")
-		}
-	}()
-
-	// Reset the resource usage to 0 when the process fully stops so that all of the UI
-	// views in the Panel correctly display 0.
-	if st == environment.ProcessOfflineState {
-		s.resources.Reset()
-		s.emitProcUsage()
-	}
-
-	// 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
-	// counter.
-	//
-	// In the event that we have passed the thresholds, don't do anything, otherwise
-	// automatically attempt to start the process back up for the user. This is done in a
-	// separate thread as to not block any actions currently taking place in the flow
-	// that called this function.
-	if (prevState == environment.ProcessStartingState || prevState == environment.ProcessRunningState) && s.Environment.State() == environment.ProcessOfflineState {
-		s.Log().Info("detected server as entering a crashed state; running crash handler")
-
-		go func(server *Server) {
-			if err := server.handleServerCrash(); err != nil {
-				if IsTooFrequentCrashError(err) {
-					server.Log().Info("did not restart server after crash; occurred too soon after the last")
-				} else {
-					s.PublishConsoleOutputFromDaemon("Server crash was detected but an error occurred while handling it.")
-					server.Log().WithField("error", err).Error("failed to handle server crash")
-				}
-			}
-		}(s)
-	}
-}
-
-// Returns the current state of the server in a race-safe manner.
-// Deprecated
-// use Environment.State()
-func (s *Server) GetState() string {
-	return s.Environment.State()
-}
-
-// Determines if the server state is running or not. This is different than the
-// environment state, it is simply the tracked state from this daemon instance, and
-// not the response from Docker.
-func (s *Server) IsRunning() bool {
-	st := s.Environment.State()
-
-	return st == environment.ProcessRunningState || st == environment.ProcessStartingState
-}
diff --git a/sftp/server.go b/sftp/server.go
index b50650d..d2260f1 100644
--- a/sftp/server.go
+++ b/sftp/server.go
@@ -24,14 +24,16 @@ import (
 
 //goland:noinspection GoNameStartsWithPackageName
 type SFTPServer struct {
+	manager  *server.Manager
 	BasePath string
 	ReadOnly bool
 	Listen   string
 }
 
-func New() *SFTPServer {
+func New(m *server.Manager) *SFTPServer {
 	cfg := config.Get().System
 	return &SFTPServer{
+		manager:  m,
 		BasePath: cfg.Data,
 		ReadOnly: cfg.Sftp.ReadOnly,
 		Listen:   cfg.Sftp.Address + ":" + strconv.Itoa(cfg.Sftp.Port),
@@ -81,7 +83,7 @@ func (c *SFTPServer) Run() error {
 
 // Handles an inbound connection to the instance and determines if we should serve the
 // request or not.
-func (c SFTPServer) AcceptInbound(conn net.Conn, config *ssh.ServerConfig) {
+func (c *SFTPServer) AcceptInbound(conn net.Conn, config *ssh.ServerConfig) {
 	// Before beginning a handshake must be performed on the incoming net.Conn
 	sconn, chans, reqs, err := ssh.NewServerConn(conn, config)
 	if err != nil {
@@ -119,7 +121,7 @@ func (c SFTPServer) AcceptInbound(conn net.Conn, config *ssh.ServerConfig) {
 		// This will also attempt to match a specific server out of the global server
 		// store and return nil if there is no match.
 		uuid := sconn.Permissions.Extensions["uuid"]
-		srv := server.GetServers().Find(func(s *server.Server) bool {
+		srv := c.manager.Find(func(s *server.Server) bool {
 			if uuid == "" {
 				return false
 			}