From ba77de12acb7b3979f437097ad218d33a8c84152 Mon Sep 17 00:00:00 2001
From: Danny Allen <52468448+daall@users.noreply.github.com>
Date: Fri, 13 Sep 2019 10:50:31 -0700
Subject: [PATCH] [cron.d] Add cron job to periodically clean-up core files
 (#3449)

* [cron.d] Create cron job to periodically clean-up core files
* Create script to scan /var/core and clean-up older core files
* Create cron job to run clean-up script

Signed-off-by: Danny Allen <daall@microsoft.com>

* Update interval for running cron job

* Respond to feedback

* Change syslog id
---
 build_debian.sh                        |  3 ++
 files/image_config/cron.d/core_cleanup |  3 ++
 files/scripts/core_cleanup.py          | 51 ++++++++++++++++++++++++++
 3 files changed, 57 insertions(+)
 create mode 100644 files/image_config/cron.d/core_cleanup
 create mode 100755 files/scripts/core_cleanup.py

diff --git a/build_debian.sh b/build_debian.sh
index 061efb8d747b..c589d4acf14f 100755
--- a/build_debian.sh
+++ b/build_debian.sh
@@ -399,6 +399,9 @@ build_number: ${BUILD_NUMBER:-0}
 built_by: $USER@$BUILD_HOSTNAME
 EOF
 
+## Copy over clean-up script
+sudo cp ./files/scripts/core_cleanup.py $FILESYSTEM_ROOT/usr/bin/core_cleanup.py
+
 ## Copy ASIC config checksum
 python files/build_scripts/generate_asic_config_checksum.py
 if [[ ! -f './asic_config_checksum' ]]; then
diff --git a/files/image_config/cron.d/core_cleanup b/files/image_config/cron.d/core_cleanup
new file mode 100644
index 000000000000..b1c379da9ebb
--- /dev/null
+++ b/files/image_config/cron.d/core_cleanup
@@ -0,0 +1,3 @@
+# Attempts to clean up core files every 2 hours
+* */2 * * * root /usr/bin/core_cleanup.py > /dev/null 2>&1
+
diff --git a/files/scripts/core_cleanup.py b/files/scripts/core_cleanup.py
new file mode 100755
index 000000000000..67620b2397de
--- /dev/null
+++ b/files/scripts/core_cleanup.py
@@ -0,0 +1,51 @@
+#!/usr/bin/env python
+
+import syslog
+import os
+
+from collections import defaultdict
+from datetime import datetime
+
+SYSLOG_IDENTIFIER = 'core_cleanup.py'
+CORE_FILE_DIR = os.path.basename(__file__)
+MAX_CORE_FILES = 4
+
+def log_info(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_INFO, msg)
+    syslog.closelog()
+
+def log_error(msg):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_ERR, msg)
+    syslog.closelog()
+
+def main():
+    if os.getuid() != 0:
+        log_error('Root required to clean up core files')
+        return
+
+    log_info('Cleaning up core files')
+    core_files = [f for f in os.listdir(CORE_FILE_DIR) if os.path.isfile(os.path.join(CORE_FILE_DIR, f))]
+
+    core_files_by_process = defaultdict(list)
+    for f in core_files:
+        process = f.split('.')[0]
+        curr_files = core_files_by_process[process]
+        curr_files.append(f)
+
+        if len(curr_files) > MAX_CORE_FILES:
+            curr_files.sort(reverse = True, key = lambda x: datetime.utcfromtimestamp(int(x.split('.')[1])))
+            oldest_core = curr_files[MAX_CORE_FILES]
+            log_info('Deleting {}'.format(oldest_core))
+            try:
+                os.remove(os.path.join(CORE_FILE_DIR, oldest_core))
+            except:
+                log_error('Unexpected error occured trying to delete {}'.format(oldest_core))
+            core_files_by_process[process] = curr_files[0:MAX_CORE_FILES]
+
+    log_info('Finished cleaning up core files')
+
+if __name__ == '__main__':
+    main()
+