From 13939379042452fff0b2402e519add22d9383dac Mon Sep 17 00:00:00 2001
From: Dane Everitt <dane@daneeveritt.com>
Date: Mon, 1 Feb 2021 20:26:15 -0800
Subject: [PATCH] Fix race condition and flawed logic mis-querying panel for
 servers; closes pterodactyl/panel#3059

---
 remote/servers.go | 28 ++++++++++++++--------------
 server/manager.go |  8 ++++----
 2 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/remote/servers.go b/remote/servers.go
index 150ae52..21b004d 100644
--- a/remote/servers.go
+++ b/remote/servers.go
@@ -71,31 +71,31 @@ func (c *client) GetServersPaged(ctx context.Context, page, limit int) ([]api.Ra
 	return r.Data, r.Meta, nil
 }
 
-func (c *client) GetServers(ctx context.Context, perPage int) ([]api.RawServerData, error) {
-	servers, pageMeta, err := c.GetServersPaged(ctx, 0, perPage)
+// GetServers returns all of the servers that are present on the Panel making
+// parallel API calls to the endpoint if more than one page of servers is returned.
+func (c *client) GetServers(ctx context.Context, limit int) ([]api.RawServerData, error) {
+	servers, meta, err := c.GetServersPaged(ctx, 0, limit)
 	if err != nil {
 		return nil, err
 	}
 
-	// if the amount of servers exceeds the page limit, get the remaining pages in parallel
-	if pageMeta.LastPage > 1 {
-		eg, _ := errgroup.WithContext(ctx)
-		serversMu := sync.Mutex{}
-
-		for page := pageMeta.CurrentPage + 1; page <= pageMeta.LastPage; page++ {
-			eg.Go(func() error {
-				ps, _, err := c.GetServersPaged(ctx, perPage, int(page))
+	var mu sync.Mutex
+	if meta.LastPage > 1 {
+		g, ctx := errgroup.WithContext(ctx)
+		for page := meta.CurrentPage + 1; page <= meta.LastPage; page++ {
+			page := page
+			g.Go(func() error {
+				ps, _, err := c.GetServersPaged(ctx, int(page), limit)
 				if err != nil {
 					return err
 				}
-				serversMu.Lock()
+				mu.Lock()
 				servers = append(servers, ps...)
-				serversMu.Unlock()
+				mu.Unlock()
 				return nil
 			})
 		}
-
-		if err := eg.Wait(); err != nil {
+		if err := g.Wait(); err != nil {
 			return nil, err
 		}
 	}
diff --git a/server/manager.go b/server/manager.go
index 1798ec0..0816a18 100644
--- a/server/manager.go
+++ b/server/manager.go
@@ -28,11 +28,11 @@ type Manager struct {
 // 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 {
+	m := NewEmptyManager()
+	if err := m.init(ctx, client); err != nil {
 		return nil, err
 	}
-	return c, nil
+	return m, nil
 }
 
 // NewEmptyManager returns a new empty manager collection without actually
@@ -44,7 +44,7 @@ func NewEmptyManager() *Manager {
 
 // 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 {
+func (m *Manager) init(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 {