(fix): Added a logrotate function to the crowdsec.go installer file

install/crowdsec.go

@@ -6,6 +6,7 @@ import (
 	"log"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
 
 	"gopkg.in/yaml.v3"
@@ -40,6 +41,8 @@ func installCrowdsec(config Config) error {
 		os.Exit(1)
 	}
 
+	setupTraefikLogRotate()
+
 	if err := copyDockerService("config/crowdsec/docker-compose.yml", "docker-compose.yml", "crowdsec"); err != nil {
 		fmt.Printf("Error copying docker service: %v\n", err)
 		os.Exit(1)
@@ -208,3 +211,80 @@ func CheckAndAddCrowdsecDependency(composePath string) error {
 	fmt.Println("Added dependency of crowdsec to traefik")
 	return nil
 }
+
+// setupTraefikLogRotate writes a logrotate config for the Traefik access log
+// that CrowdSec depends on. This is only needed when CrowdSec is installed
+// because the default Pangolin install does not enable Traefik access logs.
+//
+// copytruncate is used so Traefik does not need to be restarted or sent a
+// signal after rotation — it keeps writing to the same file descriptor while
+// the rotated copy is made and the original is truncated in place.
+func setupTraefikLogRotate() {
+	const logrotateDir = "/etc/logrotate.d"
+	const logrotateFile = "/etc/logrotate.d/pangolin-traefik"
+
+	// Resolve the absolute path to the install directory so the logrotate
+	// config references the correct log file regardless of where the user
+	// installed Pangolin.
+	installDir, err := filepath.Abs(".")
+	if err != nil {
+		fmt.Printf("[logrotate] Warning: could not resolve install directory: %v\n", err)
+		fmt.Println("[logrotate] Skipping logrotate setup. Set it up manually:")
+		printLogrotateConfig("<install_dir>/config/traefik/logs/access.log")
+		return
+	}
+
+	logPath := filepath.Join(installDir, "config/traefik/logs/access.log")
+
+	if os.Geteuid() != 0 {
+		fmt.Println("\n[logrotate] Skipping automatic logrotate setup: not running as root.")
+		fmt.Println("[logrotate] To prevent unbounded growth of the Traefik access log used by CrowdSec,")
+		fmt.Println("[logrotate] create the file /etc/logrotate.d/pangolin-traefik manually with:")
+		printLogrotateConfig(logPath)
+		return
+	}
+
+	config := fmt.Sprintf(`# Logrotate config for Traefik access logs used by CrowdSec.
+# Generated by the Pangolin installer. Safe to edit.
+%s {
+    daily
+    rotate 7
+    compress
+    delaycompress
+    missingok
+    notifempty
+    copytruncate
+}
+`, logPath)
+
+	if err := os.MkdirAll(logrotateDir, 0755); err != nil {
+		fmt.Printf("[logrotate] Warning: could not create %s: %v\n", logrotateDir, err)
+		return
+	}
+
+	if err := os.WriteFile(logrotateFile, []byte(config), 0644); err != nil {
+		fmt.Printf("[logrotate] Warning: could not write %s: %v\n", logrotateFile, err)
+		fmt.Println("[logrotate] Set it up manually:")
+		printLogrotateConfig(logPath)
+		return
+	}
+
+	fmt.Printf("[logrotate] Wrote logrotate config to %s\n", logrotateFile)
+	fmt.Println("[logrotate] Traefik access logs will be rotated daily, keeping 7 compressed copies.")
+}
+
+// printLogrotateConfig prints a logrotate config block to stdout so users can
+// set it up manually when the installer cannot write to /etc.
+func printLogrotateConfig(logPath string) {
+	fmt.Printf(`
+  %s {
+      daily
+      rotate 7
+      compress
+      delaycompress
+      missingok
+      notifempty
+      copytruncate
+  }
+`, logPath)
+}