civodul pushed a commit to branch devel
in repository shepherd.
commit 8c1c74419f4107d36acd41c03e2d0923d229c94b
Author: Ludovic Courtès <l...@gnu.org>
AuthorDate: Fri Aug 9 16:39:48 2024 +0200
system-log: Implement log rotation.
* modules/shepherd/service/system-log.scm (log-dispatcher): Implement
log rotation.
* tests/services/system-log.sh: Add ‘log-rotation’ service and test it.
* doc/shepherd.texi (System Log Service): Mention ‘log-rotation’.
(Log Rotation Service): Mention system log.
---
doc/shepherd.texi | 8 +++++--
modules/shepherd/service/system-log.scm | 21 ++++++++++++++----
tests/services/system-log.sh | 38 +++++++++++++++++++++++++++++----
3 files changed, 57 insertions(+), 10 deletions(-)
diff --git a/doc/shepherd.texi b/doc/shepherd.texi
index 29eb27e..b45bb93 100644
--- a/doc/shepherd.texi
+++ b/doc/shepherd.texi
@@ -1974,7 +1974,10 @@ configuration snippet below instantiates and registers
that service for
The configuration above starts the service under the names
@code{system-log} and @code{syslogd}. Messages are logged in files
under @file{/var/log}, on @file{/dev/tty12} (the twelfth console
-terminal on Linux), and on the console for emergency messages.
+terminal on Linux), and on the console for emergency messages. The
+@code{system-log} service is integrated with the log rotation service:
+log files it creates are subject to log rotation, in a ``race-free''
+fashion (@pxref{Log Rotation Service}).
The destination of syslog messages---the files, terminals, etc.@: where
they are written---can be configured by passing a procedure as the
@@ -2089,7 +2092,8 @@ wouldn't it be nice to archive them or even delete them
periodically?
The @dfn{log rotation} service does exactly that. Once you've enabled
it, it periodically @dfn{rotates} the log files of services---those
specified via the @code{#:log-file} argument of service constructors
-(@pxref{Service De- and Constructors})---but also, optionally,
+(@pxref{Service De- and Constructors})---those of the system log
+(@pxref{System Log Service}), and also, optionally,
``external'' log files produced by some other mechanism.
By ``rotating'' we mean this: if a service produces
diff --git a/modules/shepherd/service/system-log.scm
b/modules/shepherd/service/system-log.scm
index 097142c..51d4af7 100644
--- a/modules/shepherd/service/system-log.scm
+++ b/modules/shepherd/service/system-log.scm
@@ -22,7 +22,8 @@
#:use-module (shepherd service)
#:use-module (shepherd support)
#:autoload (shepherd config) (%localstatedir)
- #:autoload (shepherd logger) (open-log-file)
+ #:autoload (shepherd logger) (open-log-file
+ rotate-and-reopen-log-file)
#:autoload (shepherd comm) (system-log-file)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-9)
@@ -309,9 +310,21 @@ in message destination procedure: "))
'()
ports))
(loop ports))
- (('rotate requested-file rotated-file reply)
- (put-message reply #f) ;TODO: implement it
- (loop ports))
+ (('rotate file rotated-file reply)
+ (match (vhash-assoc file ports)
+ (#f
+ (local-output (l10n "Ignoring request to rotate unknown \
+system log file '~a'.")
+ file)
+ (put-message reply #f)
+ (loop ports))
+ ((_ . port)
+ (let ((port (rotate-and-reopen-log-file port file
+ rotated-file)))
+ (put-message reply (port? port))
+ (if (port? port)
+ (loop (vhash-cons file port (vhash-delete file ports)))
+ (loop ports))))))
('terminate
(local-output (l10n "Closing ~a system log ports.")
(vlist-length ports))
diff --git a/tests/services/system-log.sh b/tests/services/system-log.sh
index 78e3c15..742bcea 100644
--- a/tests/services/system-log.sh
+++ b/tests/services/system-log.sh
@@ -33,14 +33,17 @@ syslog_socket="$PWD/t-syslog-socket-$$"
herd="herd -s $socket"
-trap "cat $log || true;
- rm -f $socket $conf $log $logger $kmsg $syslog_socket;
- rm -f $syslog_file $syslog_auth_file $syslog_debug_file
$syslog_remote_file;
+trap "zcat $log* || true;
+ rm -f $socket $conf $log* $logger $kmsg $syslog_socket;
+ rm -f $syslog_file* $syslog_auth_file* $syslog_debug_file*
$syslog_remote_file*;
test -f $pid && kill \`cat $pid\` || true; rm -f $pid" EXIT
cat > "$conf" <<EOF
(use-modules (shepherd service system-log)
- (shepherd endpoints))
+ (shepherd service log-rotation)
+ (shepherd service timer)
+ (shepherd endpoints)
+ (srfi srfi-19))
(define (message-destination message)
(pk 'message-destination->
@@ -58,6 +61,14 @@ cat > "$conf" <<EOF
(else
(list "$syslog_file")))))
+(define today
+ (time-utc->date (current-time time-utc)))
+
+(define past-month
+ (if (= 1 (date-month today))
+ 12
+ (- (date-month today) 1)))
+
(define %endpoints
(list (endpoint (make-socket-address AF_UNIX "$syslog_socket")
#:style SOCK_DGRAM)
@@ -68,6 +79,10 @@ cat > "$conf" <<EOF
(list (system-log-service %endpoints
#:message-destination message-destination
#:kernel-log-file "$kmsg")
+ (log-rotation-service
+ ;; Arrange so that it does not trigger automatically.
+ (calendar-event #:months (list past-month))
+ #:rotation-size-threshold 0)
(service
'(logger)
#:requirement '(syslogd)
@@ -156,6 +171,21 @@ do
$herd status system-log | grep "Log files: .*$file"
done
+# Ensure logs can be rotated.
+$herd start log-rotation
+$herd trigger log-rotation
+for file in "$syslog_file" "$syslog_auth_file" "$syslog_debug_file" \
+ "$syslog_remote_file"
+do
+ $herd files log-rotation | grep "$file"
+
+ # Rotation happens asynchronously so wait for a while.
+ until test -f "$file.1.gz"; do sleep 0.2; done
+ gunzip < "$file.1.gz"
+ rm "$file.1.gz"
+ test -f "$file" # this one should have been recreated
+done
+
$herd stop system-log
$herd eval root '(gc)'
