From e09cc3d2dd18753562c808136bf9aeca9428914d Mon Sep 17 00:00:00 2001
From: Dane Everitt <dane@daneeveritt.com>
Date: Thu, 3 Sep 2020 20:13:51 -0700
Subject: [PATCH] Automatically write a logrotate file to the disk when wings
 boots if directory exists; closes pterodactyl/panel#2312

---
 cmd/root.go             |  8 +++++--
 config/config_system.go | 46 +++++++++++++++++++++++++++++++++++++++++
 go.mod                  |  2 +-
 templates/logrotate.tpl | 13 ++++++++++++
 4 files changed, 66 insertions(+), 3 deletions(-)
 create mode 100644 templates/logrotate.tpl

diff --git a/cmd/root.go b/cmd/root.go
index 68404a1..d8f37a1 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -133,8 +133,12 @@ func rootCmdRun(*cobra.Command, []string) {
 	config.SetDebugViaFlag(debug)
 
 	if err := c.System.ConfigureDirectories(); err != nil {
-		log.WithError(err).Fatal("failed to configure system directories for pterodactyl")
-		os.Exit(1)
+		log.WithField("error", err).Fatal("failed to configure system directories for pterodactyl")
+		return
+	}
+
+	if err := c.System.EnableLogRotation(); err != nil {
+		log.WithField("error", err).Fatal("failed to configure log rotation on the system")
 		return
 	}
 
diff --git a/config/config_system.go b/config/config_system.go
index b865cd9..fab3479 100644
--- a/config/config_system.go
+++ b/config/config_system.go
@@ -3,6 +3,7 @@ package config
 import (
 	"github.com/apex/log"
 	"github.com/pkg/errors"
+	"html/template"
 	"os"
 	"path"
 	"path/filepath"
@@ -46,6 +47,10 @@ type SystemConfiguration struct {
 	// frequently modifying a servers' files.
 	CheckPermissionsOnBoot bool `default:"true" yaml:"check_permissions_on_boot"`
 
+	// If set to false Wings will not attempt to write a log rotate configuration to the disk
+	// when it boots and one is not detected.
+	EnableLogRotate bool `default:"true" yaml:"enable_log_rotate"`
+
 	Sftp SftpConfiguration `yaml:"sftp"`
 }
 
@@ -91,6 +96,47 @@ func (sc *SystemConfiguration) ConfigureDirectories() error {
 	return nil
 }
 
+// Writes a logrotate file for wings to the system logrotate configuration directory if one
+// exists and a logrotate file is not found. This allows us to basically automate away the log
+// rotatation for most installs, but also enable users to make modifications on their own.
+func (sc *SystemConfiguration) EnableLogRotation() error {
+	// Do nothing if not enabled.
+	if sc.EnableLogRotate == false {
+		log.Info("skipping log rotate configuration, disabled in wings config file")
+
+		return nil
+	}
+
+	if st, err := os.Stat("/etc/logrotate.d"); err != nil && !os.IsNotExist(err) {
+		return errors.WithStack(err)
+	} else if (err != nil && os.IsNotExist(err)) || !st.IsDir() {
+		return nil
+	}
+
+	if _, err := os.Stat("/etc/logrotate.d/wings"); err != nil && !os.IsNotExist(err) {
+		return errors.WithStack(err)
+	} else if err == nil {
+		return nil
+	}
+
+	log.Info("no log rotation configuration found, system is configured to support it, adding file now")
+	// If we've gotten to this point it means the logrotate directory exists on the system
+	// but there is not a file for wings already. In that case, let us write a new file to
+	// it so files can be rotated easily.
+	f, err := os.Create("/etc/logrotate.d/wings")
+	if err != nil {
+		return errors.WithStack(err)
+	}
+	defer f.Close()
+
+	t, err := template.ParseFiles("templates/logrotate.tpl")
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	return errors.Wrap(t.Execute(f, sc), "failed to write logrotate file to disk")
+}
+
 // Returns the location of the JSON file that tracks server states.
 func (sc *SystemConfiguration) GetStatesPath() string {
 	return path.Join(sc.RootDirectory, "states.json")
diff --git a/go.mod b/go.mod
index e46bd66..d2d9e57 100644
--- a/go.mod
+++ b/go.mod
@@ -70,7 +70,7 @@ require (
 	golang.org/x/lint v0.0.0-20200302205851-738671d3881b // indirect
 	golang.org/x/net v0.0.0-20200707034311-ab3426394381 // indirect
 	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208
-	golang.org/x/text v0.3.3 // indirect
+	golang.org/x/text v0.3.3
 	golang.org/x/time v0.0.0-20200630173020-3af7569d3a1e // indirect
 	golang.org/x/tools v0.0.0-20200509030707-2212a7e161a5 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
diff --git a/templates/logrotate.tpl b/templates/logrotate.tpl
new file mode 100644
index 0000000..d848699
--- /dev/null
+++ b/templates/logrotate.tpl
@@ -0,0 +1,13 @@
+{{.LogDirectory}}/wings.log {
+    size 10M
+    compress
+    delaycompress
+    dateext
+    maxage 7
+    missingok
+    notifempty
+    create 0640 {{.User.Uid}} {{.User.Gid}}
+    postrotate
+        killall -SIGHUP wings
+    endscript
+}
\ No newline at end of file