[bug#55739] [PATCH 0/2] Add a verbose option for the D-Bus service.

[bug#55739] [PATCH 0/2] Add a verbose option for the D-Bus service.

[Maxim Cournoyer]

Hi Guix,

This was made some time ago to make debugging D-Bus issues easier on Guix
System.  I think it may still useful, so I'm sending it for inclusion.

Thanks,

Maxim Cournoyer (2):
  gnu: Add dbus-verbose.
  services: dbus: Add a VERBOSE? configuration option.

 doc/guix.texi         |  9 +++++++--
 gnu/packages/glib.scm | 15 +++++++++++++++
 gnu/services/dbus.scm | 22 +++++++++++++++++-----
 3 files changed, 39 insertions(+), 7 deletions(-)

-- 
2.36.0

[bug#55739] [PATCH 1/2] gnu: Add dbus-verbose.

[Maxim Cournoyer]

* gnu/packages/glib.scm (dbus-verbose): New variable.
---
 gnu/packages/glib.scm | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/gnu/packages/glib.scm b/gnu/packages/glib.scm
index 30e5433776..25bd5871b0 100644
--- a/gnu/packages/glib.scm
+++ b/gnu/packages/glib.scm
@@ -176,6 +176,21 @@ (define dbus
 shared NFS home directories.")
     (license license:gpl2+)))                     ; or Academic Free License 2.1
 
+;;; The reason this is not enabled in the regular dbus package is because it
+;;; impacts the performance of D-Bus (including its library) as a whole, even
+;;; when the DBUS_VERBOSE environment variable is not set.
+(define-public dbus-verbose
+  (package/inherit dbus
+    (name "dbus-verbose")
+    (arguments (substitute-keyword-arguments (package-arguments dbus)
+                 ((#:configure-flags flags '())
+                  `(cons "--enable-verbose-mode" ,flags))))
+    (synopsis "D-Bus with verbose mode enabled for debugging")
+    (description "This variant D-Bus package is built with verbose mode, which
+eases debugging of D-Bus services by printing various debug information when
+the @code{DBUS_VERBOSE} environment variable is set to @samp{1}.  For more
+information, refer to the @samp{dbus-daemon(1)} man page.")))
+
 (define glib
   (package
     (name "glib")
-- 
2.36.0

[bug#55739] [PATCH 2/2] services: dbus: Add a VERBOSE? configuration option.

[Maxim Cournoyer]

* gnu/services/dbus.scm (<dbus-configuration>)[verbose?]: New field.
(dbus-shepherd-service): Use it.
(dbus-service)[verbose?]: Add argument and update doc.
* doc/guix.texi (Desktop Services): Document it.
---
 doc/guix.texi         |  9 +++++++--
 gnu/services/dbus.scm | 22 +++++++++++++++++-----
 2 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 88e009fe7c..3e12af2067 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -21761,9 +21761,14 @@ The actual service definitions included in @code{%desktop-services} and
 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
 are described below.
 
-@deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
+@deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()] @
+                                       [#:verbose?]
 Return a service that runs the ``system bus'', using @var{dbus}, with
-support for @var{services}.
+support for @var{services}.  When @var{verbose?} is true, it causes the
+@samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
+verbose-enabled D-Bus package such as @code{dbus-verbose} should be
+provided as @var{dbus} in this scenario.  The verbose output is logged
+to @file{/var/log/dbus-daemon.log}.
 
 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
 facility.  Its system bus is used to allow system services to communicate
diff --git a/gnu/services/dbus.scm b/gnu/services/dbus.scm
index ef6b82c572..52cb1e3a51 100644
--- a/gnu/services/dbus.scm
+++ b/gnu/services/dbus.scm
@@ -53,7 +53,9 @@ (define-record-type* <dbus-configuration>
   (dbus      dbus-configuration-dbus              ;file-like
              (default dbus))
   (services  dbus-configuration-services          ;list of <package>
-             (default '())))
+             (default '()))
+  (verbose?  dbus-configuration-verbose?          ;boolean
+             (default #f)))
 
 (define (system-service-directory services)
   "Return the system service directory, containing @code{.service} files for
@@ -191,7 +193,7 @@ (define (dbus-activation config)
 
 (define dbus-shepherd-service
   (match-lambda
-    (($ <dbus-configuration> dbus)
+    (($ <dbus-configuration> dbus _ verbose?)
      (list (shepherd-service
             (documentation "Run the D-Bus system daemon.")
             (provision '(dbus-system))
@@ -199,6 +201,12 @@ (define dbus-shepherd-service
             (start #~(make-forkexec-constructor
                       (list (string-append #$dbus "/bin/dbus-daemon")
                             "--nofork" "--system" "--syslog-only")
+                      #$@(if verbose?
+                             ;; Since the verbose output goes to the console,
+                             ;; not syslog, add a log file to capture it.
+                             '(#:environment-variables '("DBUS_VERBOSE=1")
+                               #:log-file "/var/log/dbus-daemon.log")
+                             '())
                       #:pid-file "/var/run/dbus/pid"))
             (stop #~(make-kill-destructor)))))))
 
@@ -234,9 +242,12 @@ (define dbus-root-service-type
 bus.  It allows programs and daemons to communicate and is also responsible
 for spawning (@dfn{activating}) D-Bus services on demand.")))
 
-(define* (dbus-service #:key (dbus dbus) (services '()))
+(define* (dbus-service #:key (dbus dbus) (services '()) verbose?)
   "Return a service that runs the \"system bus\", using @var{dbus}, with
-support for @var{services}.
+support for @var{services}.  When @var{verbose?} is true, it causes the
+@samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
+verbose-enabled D-Bus package such as @code{dbus-verbose} should be provided
+as @var{dbus} in this scenario.
 
 @uref{http://dbus.freedesktop.org/, D-Bus} is an inter-process communication
 facility.  Its system bus is used to allow system services to communicate and
@@ -248,7 +259,8 @@ (define* (dbus-service #:key (dbus dbus) (services '()))
 @var{services} must be equal to @code{(list avahi)}."
   (service dbus-root-service-type
            (dbus-configuration (dbus dbus)
-                               (services services))))
+                               (services services)
+                               (verbose? verbose?))))
 
 (define (wrapped-dbus-service service program variables)
   "Return a wrapper for @var{service}, a package containing a D-Bus service,
-- 
2.36.0