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The following commit(s) were added to refs/heads/master by this push:
new db6b9d2 services: Add transmission-daemon service.
db6b9d2 is described below
commit db6b9d2f4bc59511904e8c1412d0257675c46095
Author: Simon South <si...@simonsouth.net>
AuthorDate: Sat Dec 5 10:27:55 2020 -0500
services: Add transmission-daemon service.
* gnu/services/file-sharing.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* po/packages/POTFILES.in: Add it.
* tests/services/file-sharing.scm: New file.
* Makefile.am (SCM_TESTS): Add it.
* doc/guix.texi (File-Sharing Services): New section.
Signed-off-by: 宋文武 <iyzs...@member.fsf.org>
---
Makefile.am | 1 +
doc/guix.texi | 799 +++++++++++++++++++++++++++++++++++++++
gnu/local.mk | 1 +
gnu/services/file-sharing.scm | 804 ++++++++++++++++++++++++++++++++++++++++
po/packages/POTFILES.in | 1 +
tests/services/file-sharing.scm | 59 +++
6 files changed, 1665 insertions(+)
diff --git a/Makefile.am b/Makefile.am
index 798808b..52537fb 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -475,6 +475,7 @@ SCM_TESTS = \
tests/scripts.scm \
tests/search-paths.scm \
tests/services.scm \
+ tests/services/file-sharing.scm \
tests/services/linux.scm \
tests/sets.scm \
tests/size.scm \
diff --git a/doc/guix.texi b/doc/guix.texi
index 8944f51..aba8a6b 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -14716,6 +14716,7 @@ declaration.
* Mail Services:: IMAP, POP3, SMTP, and all that.
* Messaging Services:: Messaging services.
* Telephony Services:: Telephony services.
+* File-Sharing Services:: File-sharing services.
* Monitoring Services:: Monitoring services.
* Kerberos Services:: Kerberos services.
* LDAP Services:: LDAP services.
@@ -22287,6 +22288,804 @@ If it is set your server will be linked by this host
name instead.
+@node File-Sharing Services
+@subsection File-Sharing Services
+
+The @code{(gnu services file-sharing)} module provides services that
+assist with transferring files over peer-to-peer file-sharing networks.
+
+@subsubheading Transmission Daemon Service
+
+@uref{https://transmissionbt.com/, Transmission} is a flexible
+BitTorrent client that offers a variety of graphical and command-line
+interfaces. A @code{transmission-daemon-service-type} service provides
+Transmission's headless variant, @command{transmission-daemon}, as a
+system service, allowing users to share files via BitTorrent even when
+they are not logged in.
+
+@deffn {Scheme Variable} transmission-daemon-service-type
+The service type for the Transmission Daemon BitTorrent client. Its
+value must be a @code{transmission-daemon-configuration} object as in
+this example:
+
+@lisp
+(service transmission-daemon-service-type
+ (transmission-daemon-configuration
+ ;; Restrict access to the RPC ("control") interface
+ (rpc-authentication-required? #t)
+ (rpc-username "transmission")
+ (rpc-password
+ (transmission-password-hash
+ "transmission" ; desired password
+ "uKd1uMs9")) ; arbitrary salt value
+
+ ;; Accept requests from this and other hosts on the
+ ;; local network
+ (rpc-whitelist-enabled? #t)
+ (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
+
+ ;; Limit bandwidth use during work hours
+ (alt-speed-down (* 1024 2)) ; 2 MB/s
+ (alt-speed-up 512) ; 512 kB/s
+
+ (alt-speed-time-enabled? #t)
+ (alt-speed-time-day 'weekdays)
+ (alt-speed-time-begin
+ (+ (* 60 8) 30)) ; 8:30 am
+ (alt-speed-time-end
+ (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
+@end lisp
+@end deffn
+
+Once the service is started, users can interact with the daemon through
+its Web interface (at @code{http://localhost:9091/}) or by using the
+@command{transmission-remote} command-line tool, available in the
+@code{transmission} package. (Emacs users may want to also consider the
+@code{emacs-transmission} package.) Both communicate with the daemon
+through its remote procedure call (RPC) interface, which by default is
+available to all users on the system; you may wish to change this by
+assigning values to the @code{rpc-authentication-required?},
+@code{rpc-username} and @code{rpc-password} settings, as shown in the
+example above and documented further below.
+
+The value for @code{rpc-password} must be a password hash of the type
+generated and used by Transmission clients. This can be copied verbatim
+from an existing @file{settings.json} file, if another Transmission
+client is already being used. Otherwise, the
+@code{transmission-password-hash} and @code{transmission-random-salt}
+procedures provided by this module can be used to obtain a suitable hash
+value.
+
+@deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
+Returns a string containing the result of hashing @var{password}
+together with @var{salt}, in the format recognized by Transmission
+clients for their @code{rpc-password} configuration setting.
+
+@var{salt} must be an eight-character string. The
+@code{transmission-random-salt} procedure can be used to generate a
+suitable salt value at random.
+@end deffn
+
+@deffn {Scheme Procedure} transmission-random-salt
+Returns a string containing a random, eight-character salt value of the
+type generated and used by Transmission clients, suitable for passing to
+the @code{transmission-password-hash} procedure.
+@end deffn
+
+These procedures are accessible from within a Guile REPL started with
+the @command{guix repl} command (@pxref {Invoking guix repl}). This is
+useful for obtaining a random salt value to provide as the second
+parameter to `transmission-password-hash`, as in this example session:
+
+@example
+$ guix repl
+scheme@@(guix-user)> ,use (gnu services file-sharing)
+scheme@@(guix-user)> (transmission-random-salt)
+$1 = "uKd1uMs9"
+@end example
+
+Alternatively, a complete password hash can generated in a single step:
+
+@example
+scheme@@(guix-user)> (transmission-password-hash "transmission"
+(transmission-random-salt))
+$2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
+@end example
+
+The resulting string can be used as-is for the value of
+@code{rpc-password}, allowing the password to be kept hidden even in the
+operating-system configuration.
+
+Torrent files downloaded by the daemon are directly accessible only to
+users in the ``transmission'' user group, who receive read-only access
+to the directory specified by the @code{download-dir} configuration
+setting (and also the directory specified by @code{incomplete-dir}, if
+@code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
+moved to another directory or deleted altogether using
+@command{transmission-remote} with its @code{--move} and
+@code{--remove-and-delete} options.
+
+If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
+the ``transmission'' group are able also to place @file{.torrent} files
+in the directory specified by @code{watch-dir} to have the corresponding
+torrents added by the daemon. (The @code{trash-original-torrent-files?}
+setting controls whether the daemon deletes these files after processing
+them.)
+
+Some of the daemon's configuration settings can be changed temporarily
+by @command{transmission-remote} and similar tools. To undo these
+changes, use the service's @code{reload} action to have the daemon
+reload its settings from disk:
+
+@example
+# herd reload transmission-daemon
+@end example
+
+The full set of available configuration settings is defined by the
+@code{transmission-daemon-configuration} data type.
+
+@deftp {Data Type} transmission-daemon-configuration
+The data type representing configuration settings for Transmission
+Daemon. These correspond directly to the settings recognized by
+Transmission clients in their @file{settings.json} file.
+@end deftp
+
+@c The following documentation was initially generated by
+@c (generate-transmission-daemon-documentation) in (gnu services
+@c file-sharing). Manually maintained documentation is better, so we
+@c shouldn't hesitate to edit below as needed. However if the change
+@c you want to make to this documentation can be done in an automated
+@c way, it's probably easier to change (generate-documentation) than to
+@c make it below and have to deal with the churn as Transmission Daemon
+@c updates.
+
+@c %start of fragment
+
+Available @code{transmission-daemon-configuration} fields are:
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} package
transmission
+The Transmission package to use.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer stop-wait-period
+The period, in seconds, to wait when stopping the service for
+@command{transmission-daemon} to exit before killing its process. This
+allows the daemon time to complete its housekeeping and send a final
+update to trackers as it shuts down. On slow hosts, or hosts with a
+slow network connection, this value may need to be increased.
+
+Defaults to @samp{10}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string
download-dir
+The directory to which torrent files are downloaded.
+
+Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
incomplete-dir-enabled?
+If @code{#t}, files will be held in @code{incomplete-dir} while their
+torrent is being downloaded, then moved to @code{download-dir} once the
+torrent is complete. Otherwise, files for all torrents (including those
+still being downloaded) will be placed in @code{download-dir}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string
incomplete-dir
+The directory in which files from incompletely downloaded torrents will
+be held when @code{incomplete-dir-enabled?} is @code{#t}.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
+The file mode creation mask used for downloaded files. (See the
+@command{umask} man page for more information.)
+
+Defaults to @samp{18}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
rename-partial-files?
+When @code{#t}, ``.part'' is appended to the name of partially
+downloaded files.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
preallocation-mode preallocation
+The mode by which space should be preallocated for downloaded files, one
+of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
+Specifying @code{full} will minimize disk fragmentation at a cost to
+file-creation speed.
+
+Defaults to @samp{fast}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
watch-dir-enabled?
+If @code{#t}, the directory specified by @code{watch-dir} will be
+watched for new @file{.torrent} files and the torrents they describe
+added automatically (and the original files removed, if
+@code{trash-original-torrent-files?} is @code{#t}).
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string
watch-dir
+The directory to be watched for @file{.torrent} files indicating new
+torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
trash-original-torrent-files?
+When @code{#t}, @file{.torrent} files will be deleted from the watch
+directory once their torrent has been added (see
+@code{watch-directory-enabled?}).
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
speed-limit-down-enabled?
+When @code{#t}, the daemon's download speed will be limited to the rate
+specified by @code{speed-limit-down}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer speed-limit-down
+The default global-maximum download speed, in kilobytes per second.
+
+Defaults to @samp{100}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
speed-limit-up-enabled?
+When @code{#t}, the daemon's upload speed will be limited to the rate
+specified by @code{speed-limit-up}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer speed-limit-up
+The default global-maximum upload speed, in kilobytes per second.
+
+Defaults to @samp{100}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
alt-speed-enabled?
+When @code{#t}, the alternate speed limits @code{alt-speed-down} and
+@code{alt-speed-up} are used (in place of @code{speed-limit-down} and
+@code{speed-limit-up}, if they are enabled) to constrain the daemon's
+bandwidth usage. This can be scheduled to occur automatically at
+certain times during the week; see @code{alt-speed-time-enabled?}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer alt-speed-down
+The alternate global-maximum download speed, in kilobytes per second.
+
+Defaults to @samp{50}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer alt-speed-up
+The alternate global-maximum upload speed, in kilobytes per second.
+
+Defaults to @samp{50}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
alt-speed-time-enabled?
+When @code{#t}, the alternate speed limits @code{alt-speed-down} and
+@code{alt-speed-up} will be enabled automatically during the periods
+specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
+@code{alt-time-speed-end}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} day-list
alt-speed-time-day
+The days of the week on which the alternate-speed schedule should be
+used, specified either as a list of days (@code{sunday}, @code{monday},
+and so on) or using one of the symbols @code{weekdays}, @code{weekends}
+or @code{all}.
+
+Defaults to @samp{all}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer alt-speed-time-begin
+The time of day at which to enable the alternate speed limits, expressed
+as a number of minutes since midnight.
+
+Defaults to @samp{540}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer alt-speed-time-end
+The time of day at which to disable the alternate speed limits,
+expressed as a number of minutes since midnight.
+
+Defaults to @samp{1020}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string
bind-address-ipv4
+The IP address at which to listen for peer connections, or ``0.0.0.0''
+to listen at all available IP addresses.
+
+Defaults to @samp{"0.0.0.0"}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string
bind-address-ipv6
+The IPv6 address at which to listen for peer connections, or ``::'' to
+listen at all available IPv6 addresses.
+
+Defaults to @samp{"::"}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
peer-port-random-on-start?
+If @code{#t}, when the daemon starts it will select a port at random on
+which to listen for peer connections, from the range specified
+(inclusively) by @code{peer-port-random-low} and
+@code{peer-port-random-high}. Otherwise, it listens on the port
+specified by @code{peer-port}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} port-number
peer-port-random-low
+The lowest selectable port number when @code{peer-port-random-on-start?}
+is @code{#t}.
+
+Defaults to @samp{49152}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} port-number
peer-port-random-high
+The highest selectable port number when @code{peer-port-random-on-start}
+is @code{#t}.
+
+Defaults to @samp{65535}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} port-number
peer-port
+The port on which to listen for peer connections when
+@code{peer-port-random-on-start?} is @code{#f}.
+
+Defaults to @samp{51413}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
port-forwarding-enabled?
+If @code{#t}, the daemon will attempt to configure port-forwarding on an
+upstream gateway automatically using @acronym{UPnP} and
+@acronym{NAT-PMP}.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
encryption-mode encryption
+The encryption preference for peer connections, one of
+@code{prefer-unencrypted-connections},
+@code{prefer-encrypted-connections} or
+@code{require-encrypted-connections}.
+
+Defaults to @samp{prefer-encrypted-connections}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string
peer-congestion-algorithm
+The TCP congestion-control algorithm to use for peer connections,
+specified using a string recognized by the operating system in calls to
+@code{setsockopt} (or set to @code{disabled}, in which case the
+operating-system default is used).
+
+Note that on GNU/Linux systems, the kernel must be configured to allow
+processes to use a congestion-control algorithm not in the default set;
+otherwise, it will deny these requests with ``Operation not permitted''.
+To see which algorithms are available on your system and which are
+currently permitted for use, look at the contents of the files
+@file{tcp_available_congestion_control} and
+@file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
+directory.
+
+As an example, to have Transmission Daemon use
+@uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
+congestion-control algorithm}, you'll need to modify your kernel
+configuration to build in support for the algorithm, then update your
+operating-system configuration to allow its use by adding a
+@code{sysctl-service-type} service (or updating the existing one's
+configuration) with lines like the following:
+
+@lisp
+(service sysctl-service-type
+ (sysctl-configuration
+ (settings
+ ("net.ipv4.tcp_allowed_congestion_control" .
+ "reno cubic lp"))))
+@end lisp
+
+The Transmission Daemon configuration can then be updated with
+
+@lisp
+(peer-congestion-algorithm "lp")
+@end lisp
+
+and the system reconfigured to have the changes take effect.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
tcp-type-of-service peer-socket-tos
+The type of service to request in outgoing @acronym{TCP} packets, one of
+@code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
+@code{reliability}.
+
+Defaults to @samp{default}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer peer-limit-global
+The global limit on the number of connected peers.
+
+Defaults to @samp{200}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer peer-limit-per-torrent
+The per-torrent limit on the number of connected peers.
+
+Defaults to @samp{50}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer upload-slots-per-torrent
+The maximum number of peers to which the daemon will upload data
+simultaneously for each torrent.
+
+Defaults to @samp{14}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer peer-id-ttl-hours
+The maximum lifespan, in hours, of the peer ID associated with each
+public torrent before it is regenerated.
+
+Defaults to @samp{6}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
blocklist-enabled?
+When @code{#t}, the daemon will ignore peers mentioned in the blocklist
+it has most recently downloaded from @code{blocklist-url}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string
blocklist-url
+The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
+@file{.dat} format) to be periodically downloaded and applied when
+@code{blocklist-enabled?} is @code{#t}.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
download-queue-enabled?
+If @code{#t}, the daemon will be limited to downloading at most
+@code{download-queue-size} non-stalled torrents simultaneously.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer download-queue-size
+The size of the daemon's download queue, which limits the number of
+non-stalled torrents it will download at any one time when
+@code{download-queue-enabled?} is @code{#t}.
+
+Defaults to @samp{5}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
seed-queue-enabled?
+If @code{#t}, the daemon will be limited to seeding at most
+@code{seed-queue-size} non-stalled torrents simultaneously.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer seed-queue-size
+The size of the daemon's seed queue, which limits the number of
+non-stalled torrents it will seed at any one time when
+@code{seed-queue-enabled?} is @code{#t}.
+
+Defaults to @samp{10}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
queue-stalled-enabled?
+When @code{#t}, the daemon will consider torrents for which it has not
+shared data in the past @code{queue-stalled-minutes} minutes to be
+stalled and not count them against its @code{download-queue-size} and
+@code{seed-queue-size} limits.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer queue-stalled-minutes
+The maximum period, in minutes, a torrent may be idle before it is
+considered to be stalled, when @code{queue-stalled-enabled?} is
+@code{#t}.
+
+Defaults to @samp{30}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
ratio-limit-enabled?
+When @code{#t}, a torrent being seeded will automatically be paused once
+it reaches the ratio specified by @code{ratio-limit}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-rational ratio-limit
+The ratio at which a torrent being seeded will be paused, when
+@code{ratio-limit-enabled?} is @code{#t}.
+
+Defaults to @samp{2.0}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
idle-seeding-limit-enabled?
+When @code{#t}, a torrent being seeded will automatically be paused once
+it has been idle for @code{idle-seeding-limit} minutes.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer idle-seeding-limit
+The maximum period, in minutes, a torrent being seeded may be idle
+before it is paused, when @code{idle-seeding-limit-enabled?} is
+@code{#t}.
+
+Defaults to @samp{30}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
dht-enabled?
+Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
+hash table (@acronym{DHT}) protocol}, which supports the use of
+trackerless torrents.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
lpd-enabled?
+Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
+peer discovery} (@acronym{LPD}), which allows the discovery of peers on
+the local network and may reduce the amount of data sent over the public
+Internet.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
pex-enabled?
+Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
+(@acronym{PEX}), which reduces the daemon's reliance on external
+trackers and may improve its performance.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
utp-enabled?
+Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
+transport protocol} (@acronym{uTP}), which aims to reduce the impact of
+BitTorrent traffic on other users of the local network while maintaining
+full utilization of the available bandwidth.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
rpc-enabled?
+If @code{#t}, enable the remote procedure call (@acronym{RPC})
+interface, which allows remote control of the daemon via its Web
+interface, the @command{transmission-remote} command-line client, and
+similar tools.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string
rpc-bind-address
+The IP address at which to listen for @acronym{RPC} connections, or
+``0.0.0.0'' to listen at all available IP addresses.
+
+Defaults to @samp{"0.0.0.0"}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} port-number
rpc-port
+The port on which to listen for @acronym{RPC} connections.
+
+Defaults to @samp{9091}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
+The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
+
+Defaults to @samp{"/transmission/"}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
rpc-authentication-required?
+When @code{#t}, clients must authenticate (see @code{rpc-username} and
+@code{rpc-password}) when using the @acronym{RPC} interface. Note this
+has the side effect of disabling host-name whitelisting (see
+@code{rpc-host-whitelist-enabled?}.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string
rpc-username
+The username required by clients to access the @acronym{RPC} interface
+when @code{rpc-authentication-required?} is @code{#t}.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
maybe-transmission-password-hash rpc-password
+The password required by clients to access the @acronym{RPC} interface
+when @code{rpc-authentication-required?} is @code{#t}. This must be
+specified using a password hash in the format recognized by Transmission
+clients, either copied from an existing @file{settings.json} file or
+generated using the @code{transmission-password-hash} procedure.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
rpc-whitelist-enabled?
+When @code{#t}, @acronym{RPC} requests will be accepted only when they
+originate from an address specified in @code{rpc-whitelist}.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string-list
rpc-whitelist
+The list of IP and IPv6 addresses from which @acronym{RPC} requests will
+be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
+may be specified using @samp{*}.
+
+Defaults to @samp{("127.0.0.1" "::1")}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
rpc-host-whitelist-enabled?
+When @code{#t}, @acronym{RPC} requests will be accepted only when they
+are addressed to a host named in @code{rpc-host-whitelist}. Note that
+requests to ``localhost'' or ``localhost.'', or to a numeric address,
+are always accepted regardless of these settings.
+
+Note also this functionality is disabled when
+@code{rpc-authentication-required?} is @code{#t}.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} string-list
rpc-host-whitelist
+The list of host names recognized by the @acronym{RPC} server when
+@code{rpc-host-whitelist-enabled?} is @code{#t}.
+
+Defaults to @samp{()}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} message-level
message-level
+The minimum severity level of messages to be logged (to
+@file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
+logging), @code{error}, @code{info} and @code{debug}.
+
+Defaults to @samp{info}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
start-added-torrents?
+When @code{#t}, torrents are started as soon as they are added;
+otherwise, they are added in ``paused'' state.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
script-torrent-done-enabled?
+When @code{#t}, the script specified by
+@code{script-torrent-done-filename} will be invoked each time a torrent
+completes.
+
+Defaults to @samp{#f}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
maybe-file-object script-torrent-done-filename
+A file name or file-like object specifying a script to run each time a
+torrent completes, when @code{script-torrent-done-enabled?} is
+@code{#t}.
+
+Defaults to @samp{disabled}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
scrape-paused-torrents-enabled?
+When @code{#t}, the daemon will scrape trackers for a torrent even when
+the torrent is paused.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter}
non-negative-integer cache-size-mb
+The amount of memory, in megabytes, to allocate for the daemon's
+in-memory cache. A larger value may increase performance by reducing
+the frequency of disk I/O.
+
+Defaults to @samp{4}.
+
+@end deftypevr
+
+@deftypevr {@code{transmission-daemon-configuration} parameter} boolean
prefetch-enabled?
+When @code{#t}, the daemon will try to improve I/O performance by
+hinting to the operating system which data is likely to be read next
+from disk to satisfy requests from peers.
+
+Defaults to @samp{#t}.
+
+@end deftypevr
+
+
+@c %end of fragment
+
+
+
@node Monitoring Services
@subsection Monitoring Services
diff --git a/gnu/local.mk b/gnu/local.mk
index d098c04..0625c6c 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -605,6 +605,7 @@ GNU_SYSTEM_MODULES = \
%D%/services/dns.scm \
%D%/services/docker.scm \
%D%/services/authentication.scm \
+ %D%/services/file-sharing.scm \
%D%/services/games.scm \
%D%/services/ganeti.scm \
%D%/services/getmail.scm \
diff --git a/gnu/services/file-sharing.scm b/gnu/services/file-sharing.scm
new file mode 100644
index 0000000..72cd647
--- /dev/null
+++ b/gnu/services/file-sharing.scm
@@ -0,0 +1,804 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2020 Simon South <si...@simonsouth.net>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu services file-sharing)
+ #:use-module (gcrypt base16)
+ #:use-module (gcrypt hash)
+ #:use-module (gcrypt random)
+ #:use-module (gnu services)
+ #:use-module (gnu services admin)
+ #:use-module (gnu services configuration)
+ #:use-module (gnu services shepherd)
+ #:use-module (gnu packages admin)
+ #:use-module (gnu packages bittorrent)
+ #:use-module (gnu packages gnupg)
+ #:use-module (gnu packages guile)
+ #:use-module (gnu system shadow)
+ #:use-module (guix diagnostics)
+ #:use-module (guix gexp)
+ #:use-module (guix i18n)
+ #:use-module (guix modules)
+ #:use-module (guix packages)
+ #:use-module (guix records)
+ #:use-module (ice-9 format)
+ #:use-module (ice-9 match)
+ #:use-module (rnrs bytevectors)
+ #:use-module (srfi srfi-1)
+ #:use-module (srfi srfi-34)
+ #:use-module (srfi srfi-35)
+ #:export (transmission-daemon-configuration
+ transmission-daemon-service-type
+ transmission-password-hash
+ transmission-random-salt))
+
+;;;
+;;; Transmission Daemon.
+;;;
+
+(define %transmission-daemon-user "transmission")
+(define %transmission-daemon-group "transmission")
+
+(define %transmission-daemon-configuration-directory
+ "/var/lib/transmission-daemon")
+(define %transmission-daemon-log-file
+ "/var/log/transmission.log")
+
+(define %transmission-salt-length 8)
+
+(define (transmission-password-hash password salt)
+ "Returns a string containing the result of hashing @var{password} together
+with @var{salt}, in the format recognized by Transmission clients for their
+@code{rpc-password} configuration setting.
+
+@var{salt} must be an eight-character string. The
+@code{transmission-random-salt} procedure can be used to generate a suitable
+salt value at random."
+ (if (not (and (string? salt)
+ (eq? (string-length salt) %transmission-salt-length)))
+ (raise (formatted-message
+ (G_ "salt value must be a string of ~d characters")
+ %transmission-salt-length))
+ (string-append "{"
+ (bytevector->base16-string
+ (sha1 (string->utf8 (string-append password salt))))
+ salt)))
+
+(define (transmission-random-salt)
+ "Returns a string containing a random, eight-character salt value of the
+type generated and used by Transmission clients, suitable for passing to the
+@code{transmission-password-hash} procedure."
+ ;; This implementation matches a portion of Transmission's tr_ssha1
+ ;; function. See libtransmission/crypto-utils.c in the Transmission source
+ ;; distribution.
+ (let ((salter (string-append "0123456789"
+ "abcdefghijklmnopqrstuvwxyz"
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "./")))
+ (list->string
+ (map (lambda (u8)
+ (string-ref salter (modulo u8 (string-length salter))))
+ (bytevector->u8-list
+ (gen-random-bv %transmission-salt-length %gcry-strong-random))))))
+
+(define (uglify-field-name field-name)
+ (string-delete #\? (symbol->string field-name)))
+
+(define (serialize-field field-name val)
+ ;; "Serialize" each configuration field as a G-expression containing a
+ ;; name-value pair, the collection of which will subsequently be serialized
+ ;; to disk as a JSON object.
+ #~(#$(uglify-field-name field-name) . #$val))
+
+(define serialize-boolean serialize-field)
+(define serialize-integer serialize-field)
+(define serialize-rational serialize-field)
+
+(define serialize-string serialize-field)
+(define-maybe string)
+;; Override the definition of "serialize-maybe-string", as we need to output a
+;; name-value pair for the JSON builder.
+(set! serialize-maybe-string
+ (lambda (field-name val)
+ (serialize-string field-name
+ (if (and (symbol? val)
+ (eq? val 'disabled))
+ ""
+ val))))
+
+(define (string-list? val)
+ (and (list? val)
+ (and-map (lambda (x)
+ (and (string? x)
+ (not (string-index x #\,))))
+ val)))
+(define (serialize-string-list field-name val)
+ (serialize-field field-name (string-join val ",")))
+
+(define days
+ '((sunday . #b0000001)
+ (monday . #b0000010)
+ (tuesday . #b0000100)
+ (wednesday . #b0001000)
+ (thursday . #b0010000)
+ (friday . #b0100000)
+ (saturday . #b1000000)))
+(define day-lists
+ (list (cons 'weekdays '(monday tuesday wednesday thursday friday))
+ (cons 'weekends '(saturday sunday))
+ (cons 'all (map car days))))
+(define (day-list? val)
+ (or (and (symbol? val)
+ (assq val day-lists))
+ (and (list? val)
+ (and-map (lambda (x)
+ (and (symbol? x)
+ (assq x days)))
+ val))))
+(define (serialize-day-list field-name val)
+ (serialize-integer field-name
+ (reduce logior
+ #b0000000
+ (map (lambda (day)
+ (assq-ref days day))
+ (if (symbol? val)
+ (assq-ref day-lists val)
+ val)))))
+
+(define encryption-modes
+ '((prefer-unencrypted-connections . 0)
+ (prefer-encrypted-connections . 1)
+ (require-encrypted-connections . 2)))
+(define (encryption-mode? val)
+ (and (symbol? val)
+ (assq val encryption-modes)))
+(define (serialize-encryption-mode field-name val)
+ (serialize-integer field-name (assq-ref encryption-modes val)))
+
+(define serialize-file-like serialize-field)
+
+(define (file-object? val)
+ (or (string? val)
+ (file-like? val)))
+(define (serialize-file-object field-name val)
+ (if (file-like? val)
+ (serialize-file-like field-name val)
+ (serialize-string field-name val)))
+(define-maybe file-object)
+(set! serialize-maybe-file-object
+ (lambda (field-name val)
+ (if (and (symbol? val)
+ (eq? val 'disabled))
+ (serialize-string field-name "")
+ (serialize-file-object field-name val))))
+
+(define (file-object-list? val)
+ (and (list? val)
+ (and-map file-object? val)))
+(define serialize-file-object-list serialize-field)
+
+(define message-levels
+ '((none . 0)
+ (error . 1)
+ (info . 2)
+ (debug . 3)))
+(define (message-level? val)
+ (and (symbol? val)
+ (assq val message-levels)))
+(define (serialize-message-level field-name val)
+ (serialize-integer field-name (assq-ref message-levels val)))
+
+(define (non-negative-integer? val)
+ (and (integer? val)
+ (not (negative? val))))
+(define serialize-non-negative-integer serialize-integer)
+
+(define (non-negative-rational? val)
+ (and (rational? val)
+ (not (negative? val))))
+(define serialize-non-negative-rational serialize-rational)
+
+(define (port-number? val)
+ (and (integer? val)
+ (>= val 1)
+ (<= val 65535)))
+(define serialize-port-number serialize-integer)
+
+(define preallocation-modes
+ '((none . 0)
+ (fast . 1)
+ (sparse . 1)
+ (full . 2)))
+(define (preallocation-mode? val)
+ (and (symbol? val)
+ (assq val preallocation-modes)))
+(define (serialize-preallocation-mode field-name val)
+ (serialize-integer field-name (assq-ref preallocation-modes val)))
+
+(define tcp-types-of-service
+ '((default . "default")
+ (low-cost . "lowcost")
+ (throughput . "throughput")
+ (low-delay . "lowdelay")
+ (reliability . "reliability")))
+(define (tcp-type-of-service? val)
+ (and (symbol? val)
+ (assq val tcp-types-of-service)))
+(define (serialize-tcp-type-of-service field-name val)
+ (serialize-string field-name (assq-ref tcp-types-of-service val)))
+
+(define (transmission-password-hash? val)
+ (and (string? val)
+ (= (string-length val) 49)
+ (eqv? (string-ref val 0) #\{)
+ (string-every char-set:hex-digit val 1 41)))
+(define serialize-transmission-password-hash serialize-string)
+(define-maybe transmission-password-hash)
+(set! serialize-maybe-transmission-password-hash serialize-maybe-string)
+
+(define (umask? val)
+ (and (integer? val)
+ (>= val #o000)
+ (<= val #o777)))
+(define serialize-umask serialize-integer) ; must use decimal representation
+
+(define-configuration transmission-daemon-configuration
+ ;; Settings internal to this service definition.
+ (transmission
+ (package transmission)
+ "The Transmission package to use.")
+ (stop-wait-period
+ (non-negative-integer 10)
+ "The period, in seconds, to wait when stopping the service for
+@command{transmission-daemon} to exit before killing its process. This allows
+the daemon time to complete its housekeeping and send a final update to
+trackers as it shuts down. On slow hosts, or hosts with a slow network
+connection, this value may need to be increased.")
+
+ ;; Files and directories.
+ (download-dir
+ (string (string-append %transmission-daemon-configuration-directory
+ "/downloads"))
+ "The directory to which torrent files are downloaded.")
+ (incomplete-dir-enabled?
+ (boolean #f)
+ "If @code{#t}, files will be held in @code{incomplete-dir} while their
+torrent is being downloaded, then moved to @code{download-dir} once the
+torrent is complete. Otherwise, files for all torrents (including those still
+being downloaded) will be placed in @code{download-dir}.")
+ (incomplete-dir
+ (maybe-string 'disabled)
+ "The directory in which files from incompletely downloaded torrents will be
+held when @code{incomplete-dir-enabled?} is @code{#t}.")
+ (umask
+ (umask #o022)
+ "The file mode creation mask used for downloaded files. (See the
+@command{umask} man page for more information.)")
+ (rename-partial-files?
+ (boolean #t)
+ "When @code{#t}, ``.part'' is appended to the name of partially downloaded
+files.")
+ (preallocation
+ (preallocation-mode 'fast)
+ "The mode by which space should be preallocated for downloaded files, one
+of @code{none}, @code{fast} (or @code{sparse}) and @code{full}. Specifying
+@code{full} will minimize disk fragmentation at a cost to file-creation
+speed.")
+ (watch-dir-enabled?
+ (boolean #f)
+ "If @code{#t}, the directory specified by @code{watch-dir} will be watched
+for new @file{.torrent} files and the torrents they describe added
+automatically (and the original files removed, if
+@code{trash-original-torrent-files?} is @code{#t}).")
+ (watch-dir
+ (maybe-string 'disabled)
+ "The directory to be watched for @file{.torrent} files indicating new
+torrents to be added, when @code{watch-dir-enabled} is @code{#t}.")
+ (trash-original-torrent-files?
+ (boolean #f)
+ "When @code{#t}, @file{.torrent} files will be deleted from the watch
+directory once their torrent has been added (see
+@code{watch-directory-enabled?}).")
+
+ ;; Bandwidth limits.
+ (speed-limit-down-enabled?
+ (boolean #f)
+ "When @code{#t}, the daemon's download speed will be limited to the rate
+specified by @code{speed-limit-down}.")
+ (speed-limit-down
+ (non-negative-integer 100)
+ "The default global-maximum download speed, in kilobytes per second.")
+ (speed-limit-up-enabled?
+ (boolean #f)
+ "When @code{#t}, the daemon's upload speed will be limited to the rate
+specified by @code{speed-limit-up}.")
+ (speed-limit-up
+ (non-negative-integer 100)
+ "The default global-maximum upload speed, in kilobytes per second.")
+ (alt-speed-enabled?
+ (boolean #f)
+ "When @code{#t}, the alternate speed limits @code{alt-speed-down} and
+@code{alt-speed-up} are used (in place of @code{speed-limit-down} and
+@code{speed-limit-up}, if they are enabled) to constrain the daemon's
+bandwidth usage. This can be scheduled to occur automatically at certain
+times during the week; see @code{alt-speed-time-enabled?}.")
+ (alt-speed-down
+ (non-negative-integer 50)
+ "The alternate global-maximum download speed, in kilobytes per second.")
+ (alt-speed-up
+ (non-negative-integer 50)
+ "The alternate global-maximum upload speed, in kilobytes per second.")
+
+ ;; Bandwidth-limit scheduling.
+ (alt-speed-time-enabled?
+ (boolean #f)
+ "When @code{#t}, the alternate speed limits @code{alt-speed-down} and
+@code{alt-speed-up} will be enabled automatically during the periods specified
+by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
+@code{alt-time-speed-end}.")
+ (alt-speed-time-day
+ (day-list 'all)
+ "The days of the week on which the alternate-speed schedule should be used,
+specified either as a list of days (@code{sunday}, @code{monday}, and so on)
+or using one of the symbols @code{weekdays}, @code{weekends} or @code{all}.")
+ (alt-speed-time-begin
+ (non-negative-integer 540)
+ "The time of day at which to enable the alternate speed limits,
+expressed as a number of minutes since midnight.")
+ (alt-speed-time-end
+ (non-negative-integer 1020)
+ "The time of day at which to disable the alternate speed limits,
+expressed as a number of minutes since midnight.")
+
+ ;; Peer networking.
+ (bind-address-ipv4
+ (string "0.0.0.0")
+ "The IP address at which to listen for peer connections, or ``0.0.0.0'' to
+listen at all available IP addresses.")
+ (bind-address-ipv6
+ (string "::")
+ "The IPv6 address at which to listen for peer connections, or ``::'' to
+listen at all available IPv6 addresses.")
+ (peer-port-random-on-start?
+ (boolean #f)
+ "If @code{#t}, when the daemon starts it will select a port at random on
+which to listen for peer connections, from the range specified (inclusively)
+by @code{peer-port-random-low} and @code{peer-port-random-high}. Otherwise,
+it listens on the port specified by @code{peer-port}.")
+ (peer-port-random-low
+ (port-number 49152)
+ "The lowest selectable port number when @code{peer-port-random-on-start?}
+is @code{#t}.")
+ (peer-port-random-high
+ (port-number 65535)
+ "The highest selectable port number when @code{peer-port-random-on-start}
+is @code{#t}.")
+ (peer-port
+ (port-number 51413)
+ "The port on which to listen for peer connections when
+@code{peer-port-random-on-start?} is @code{#f}.")
+ (port-forwarding-enabled?
+ (boolean #t)
+ "If @code{#t}, the daemon will attempt to configure port-forwarding on an
+upstream gateway automatically using @acronym{UPnP} and @acronym{NAT-PMP}.")
+ (encryption
+ (encryption-mode 'prefer-encrypted-connections)
+ "The encryption preference for peer connections, one of
+@code{prefer-unencrypted-connections}, @code{prefer-encrypted-connections} or
+@code{require-encrypted-connections}.")
+ (peer-congestion-algorithm
+ (maybe-string 'disabled)
+ "The TCP congestion-control algorithm to use for peer connections,
+specified using a string recognized by the operating system in calls to
+@code{setsockopt} (or set to @code{disabled}, in which case the
+operating-system default is used).
+
+Note that on GNU/Linux systems, the kernel must be configured to allow
+processes to use a congestion-control algorithm not in the default set;
+otherwise, it will deny these requests with ``Operation not permitted''. To
+see which algorithms are available on your system and which are currently
+permitted for use, look at the contents of the files
+@file{tcp_available_congestion_control} and
+@file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
+directory.
+
+As an example, to have Transmission Daemon use
+@uref{http://www-ece.rice.edu/networks/TCP-LP/, the TCP Low Priority
+congestion-control algorithm}, you'll need to modify your kernel configuration
+to build in support for the algorithm, then update your operating-system
+configuration to allow its use by adding a @code{sysctl-service-type}
+service (or updating the existing one's configuration) with lines like the
+following:
+
+@lisp
+(service sysctl-service-type
+ (sysctl-configuration
+ (settings
+ (\"net.ipv4.tcp_allowed_congestion_control\" .
+ \"reno cubic lp\"))))
+@end lisp
+
+The Transmission Daemon configuration can then be updated with
+
+@lisp
+(peer-congestion-algorithm \"lp\")
+@end lisp
+
+and the system reconfigured to have the changes take effect.")
+ (peer-socket-tos
+ (tcp-type-of-service 'default)
+ "The type of service to request in outgoing @acronym{TCP} packets,
+one of @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay}
+and @code{reliability}.")
+ (peer-limit-global
+ (non-negative-integer 200)
+ "The global limit on the number of connected peers.")
+ (peer-limit-per-torrent
+ (non-negative-integer 50)
+ "The per-torrent limit on the number of connected peers.")
+ (upload-slots-per-torrent
+ (non-negative-integer 14)
+ "The maximum number of peers to which the daemon will upload data
+simultaneously for each torrent.")
+ (peer-id-ttl-hours
+ (non-negative-integer 6)
+ "The maximum lifespan, in hours, of the peer ID associated with each public
+torrent before it is regenerated.")
+
+ ;; Peer blocklists.
+ (blocklist-enabled?
+ (boolean #f)
+ "When @code{#t}, the daemon will ignore peers mentioned in the blocklist it
+has most recently downloaded from @code{blocklist-url}.")
+ (blocklist-url
+ (maybe-string 'disabled)
+ "The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
+@file{.dat} format) to be periodically downloaded and applied when
+@code{blocklist-enabled?} is @code{#t}.")
+
+ ;; Queueing.
+ (download-queue-enabled?
+ (boolean #t)
+ "If @code{#t}, the daemon will be limited to downloading at most
+@code{download-queue-size} non-stalled torrents simultaneously.")
+ (download-queue-size
+ (non-negative-integer 5)
+ "The size of the daemon's download queue, which limits the number of
+non-stalled torrents it will download at any one time when
+@code{download-queue-enabled?} is @code{#t}.")
+ (seed-queue-enabled?
+ (boolean #f)
+ "If @code{#t}, the daemon will be limited to seeding at most
+@code{seed-queue-size} non-stalled torrents simultaneously.")
+ (seed-queue-size
+ (non-negative-integer 10)
+ "The size of the daemon's seed queue, which limits the number of
+non-stalled torrents it will seed at any one time when
+@code{seed-queue-enabled?} is @code{#t}.")
+ (queue-stalled-enabled?
+ (boolean #t)
+ "When @code{#t}, the daemon will consider torrents for which it has not
+shared data in the past @code{queue-stalled-minutes} minutes to be stalled and
+not count them against its @code{download-queue-size} and
+@code{seed-queue-size} limits.")
+ (queue-stalled-minutes
+ (non-negative-integer 30)
+ "The maximum period, in minutes, a torrent may be idle before it is
+considered to be stalled, when @code{queue-stalled-enabled?} is @code{#t}.")
+
+ ;; Seeding limits.
+ (ratio-limit-enabled?
+ (boolean #f)
+ "When @code{#t}, a torrent being seeded will automatically be paused once
+it reaches the ratio specified by @code{ratio-limit}.")
+ (ratio-limit
+ (non-negative-rational 2.0)
+ "The ratio at which a torrent being seeded will be paused, when
+@code{ratio-limit-enabled?} is @code{#t}.")
+ (idle-seeding-limit-enabled?
+ (boolean #f)
+ "When @code{#t}, a torrent being seeded will automatically be paused once
+it has been idle for @code{idle-seeding-limit} minutes.")
+ (idle-seeding-limit
+ (non-negative-integer 30)
+ "The maximum period, in minutes, a torrent being seeded may be idle before
+it is paused, when @code{idle-seeding-limit-enabled?} is @code{#t}.")
+
+ ;; BitTorrent extensions.
+ (dht-enabled?
+ (boolean #t)
+ "Enable @uref{http://bittorrent.org/beps/bep_0005.html, the distributed
+hash table (@acronym{DHT}) protocol}, which supports the use of trackerless
+torrents.")
+ (lpd-enabled?
+ (boolean #f)
+ "Enable @url{https://en.wikipedia.org/wiki/Local_Peer_Discovery, local peer
+discovery} (@acronym{LPD}), which allows the discovery of peers on the local
+network and may reduce the amount of data sent over the public Internet.")
+ (pex-enabled?
+ (boolean #t)
+ "Enable @url{https://en.wikipedia.org/wiki/Peer_exchange, peer
+exchange} (@acronym{PEX}), which reduces the daemon's reliance on external
+trackers and may improve its performance.")
+ (utp-enabled?
+ (boolean #t)
+ "Enable @url{http://bittorrent.org/beps/bep_0029.html, the micro transport
+protocol} (@acronym{uTP}), which aims to reduce the impact of BitTorrent
+traffic on other users of the local network while maintaining full utilization
+of the available bandwidth.")
+
+ ;; Remote procedure call (RPC) interface.
+ (rpc-enabled?
+ (boolean #t)
+ "If @code{#t}, enable the remote procedure call (@acronym{RPC}) interface,
+which allows remote control of the daemon via its Web interface, the
+@command{transmission-remote} command-line client, and similar tools.")
+ (rpc-bind-address
+ (string "0.0.0.0")
+ "The IP address at which to listen for @acronym{RPC} connections, or
+``0.0.0.0'' to listen at all available IP addresses.")
+ (rpc-port
+ (port-number 9091)
+ "The port on which to listen for @acronym{RPC} connections.")
+ (rpc-url
+ (string "/transmission/")
+ "The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.")
+ (rpc-authentication-required?
+ (boolean #f)
+ "When @code{#t}, clients must authenticate (see @code{rpc-username} and
+@code{rpc-password}) when using the @acronym{RPC} interface. Note this has
+the side effect of disabling host-name whitelisting (see
+@code{rpc-host-whitelist-enabled?}.")
+ (rpc-username
+ (maybe-string 'disabled)
+ "The username required by clients to access the @acronym{RPC} interface
+when @code{rpc-authentication-required?} is @code{#t}.")
+ (rpc-password
+ (maybe-transmission-password-hash 'disabled)
+ "The password required by clients to access the @acronym{RPC} interface
+when @code{rpc-authentication-required?} is @code{#t}. This must be specified
+using a password hash in the format recognized by Transmission clients, either
+copied from an existing @file{settings.json} file or generated using the
+@code{transmission-password-hash} procedure.")
+ (rpc-whitelist-enabled?
+ (boolean #t)
+ "When @code{#t}, @acronym{RPC} requests will be accepted only when they
+originate from an address specified in @code{rpc-whitelist}.")
+ (rpc-whitelist
+ (string-list '("127.0.0.1" "::1"))
+ "The list of IP and IPv6 addresses from which @acronym{RPC} requests will
+be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards may be
+specified using @samp{*}.")
+ (rpc-host-whitelist-enabled?
+ (boolean #t)
+ "When @code{#t}, @acronym{RPC} requests will be accepted only when they are
+addressed to a host named in @code{rpc-host-whitelist}. Note that requests to
+``localhost'' or ``localhost.'', or to a numeric address, are always accepted
+regardless of these settings.
+
+Note also this functionality is disabled when
+@code{rpc-authentication-required?} is @code{#t}.")
+ (rpc-host-whitelist
+ (string-list '())
+ "The list of host names recognized by the @acronym{RPC} server when
+@code{rpc-host-whitelist-enabled?} is @code{#t}.")
+
+ ;; Miscellaneous.
+ (message-level
+ (message-level 'info)
+ "The minimum severity level of messages to be logged (to
+@file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
+logging), @code{error}, @code{info} and @code{debug}.")
+ (start-added-torrents?
+ (boolean #t)
+ "When @code{#t}, torrents are started as soon as they are added; otherwise,
+they are added in ``paused'' state.")
+ (script-torrent-done-enabled?
+ (boolean #f)
+ "When @code{#t}, the script specified by
+@code{script-torrent-done-filename} will be invoked each time a torrent
+completes.")
+ (script-torrent-done-filename
+ (maybe-file-object 'disabled)
+ "A file name or file-like object specifying a script to run each time a
+torrent completes, when @code{script-torrent-done-enabled?} is @code{#t}.")
+ (scrape-paused-torrents-enabled?
+ (boolean #t)
+ "When @code{#t}, the daemon will scrape trackers for a torrent even when
+the torrent is paused.")
+ (cache-size-mb
+ (non-negative-integer 4)
+ "The amount of memory, in megabytes, to allocate for the daemon's in-memory
+cache. A larger value may increase performance by reducing the frequency of
+disk I/O.")
+ (prefetch-enabled?
+ (boolean #t)
+ "When @code{#t}, the daemon will try to improve I/O performance by hinting
+to the operating system which data is likely to be read next from disk to
+satisfy requests from peers."))
+
+(define (transmission-daemon-shepherd-service config)
+ "Return a <shepherd-service> for Transmission Daemon with CONFIG."
+ (let ((transmission
+ (transmission-daemon-configuration-transmission config))
+ (stop-wait-period
+ (transmission-daemon-configuration-stop-wait-period config)))
+ (list
+ (shepherd-service
+ (provision '(transmission-daemon transmission bittorrent))
+ (requirement '(networking))
+ (documentation "Share files using the BitTorrent protocol.")
+ (start #~(make-forkexec-constructor
+ '(#$(file-append transmission "/bin/transmission-daemon")
+ "--config-dir"
+ #$%transmission-daemon-configuration-directory
+ "--foreground")
+ #:user #$%transmission-daemon-user
+ #:group #$%transmission-daemon-group
+ #:directory #$%transmission-daemon-configuration-directory
+ #:log-file #$%transmission-daemon-log-file
+ #:environment-variables
+ '("CURL_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt")))
+ (stop #~(lambda (pid)
+ (kill pid SIGTERM)
+
+ ;; Transmission Daemon normally needs some time to shut down,
+ ;; as it will complete some housekeeping and send a final
+ ;; update to trackers before it exits.
+ ;;
+ ;; Wait a reasonable period for it to stop before continuing.
+ ;; If we don't do this, restarting the service can fail as the
+ ;; new daemon process finds the old one still running and
+ ;; attached to the port used for peer connections.
+ (let wait-before-killing ((period #$stop-wait-period))
+ (if (zero? (car (waitpid pid WNOHANG)))
+ (if (positive? period)
+ (begin
+ (sleep 1)
+ (wait-before-killing (- period 1)))
+ (begin
+ (format #t
+ #$(G_ "Wait period expired; killing \
+transmission-daemon (pid ~a).~%")
+ pid)
+ (display #$(G_ "(If you see this message \
+regularly, you may need to increase the value
+of 'stop-wait-period' in the service configuration.)\n"))
+ (kill pid SIGKILL)))))
+ #f))
+ (actions
+ (list
+ (shepherd-action
+ (name 'reload)
+ (documentation "Reload the settings file from disk.")
+ (procedure #~(lambda (pid)
+ (if pid
+ (begin
+ (kill pid SIGHUP)
+ (display #$(G_ "Service transmission-daemon has \
+been asked to reload its settings file.")))
+ (display #$(G_ "Service transmission-daemon is not
\
+running."))))))))))))
+
+(define %transmission-daemon-accounts
+ (list (user-group
+ (name %transmission-daemon-group)
+ (system? #t))
+ (user-account
+ (name %transmission-daemon-user)
+ (group %transmission-daemon-group)
+ (comment "Transmission Daemon service account")
+ (home-directory %transmission-daemon-configuration-directory)
+ (shell (file-append shadow "/sbin/nologin"))
+ (system? #t))))
+
+(define %transmission-daemon-log-rotations
+ (list (log-rotation
+ (files (list %transmission-daemon-log-file)))))
+
+(define (transmission-daemon-computed-settings-file config)
+ "Return a @code{computed-file} object that, when unquoted in a G-expression,
+produces a Transmission settings file (@file{settings.json}) matching CONFIG."
+ (let ((settings
+ ;; "Serialize" the configuration settings as a list of G-expressions
+ ;; containing a name-value pair, which will ultimately be sorted and
+ ;; serialized to the settings file as a JSON object.
+ (map
+ (lambda (field)
+ ((configuration-field-serializer field)
+ (configuration-field-name field)
+ ((configuration-field-getter field) config)))
+ (filter
+ (lambda (field)
+ ;; Omit configuration fields that are used only internally by
+ ;; this service definition.
+ (not (memq (configuration-field-name field)
+ '(transmission stop-wait-period))))
+ transmission-daemon-configuration-fields))))
+ (computed-file
+ "settings.json"
+ (with-extensions (list guile-gcrypt guile-json-4)
+ (with-imported-modules (source-module-closure '((json builder)))
+ #~(begin
+ (use-modules (json builder))
+
+ (with-output-to-file #$output
+ (lambda ()
+ (scm->json (sort-list '(#$@settings)
+ (lambda (x y)
+ (string<=? (car x) (car y))))
+ #:pretty #t)))))))))
+
+(define (transmission-daemon-activation config)
+ "Return the Transmission Daemon activation GEXP for CONFIG."
+ (let ((config-dir %transmission-daemon-configuration-directory)
+ (incomplete-dir-enabled
+ (transmission-daemon-configuration-incomplete-dir-enabled? config))
+ (incomplete-dir
+ (transmission-daemon-configuration-incomplete-dir config))
+ (watch-dir-enabled
+ (transmission-daemon-configuration-watch-dir-enabled? config))
+ (watch-dir
+ (transmission-daemon-configuration-watch-dir config)))
+ (with-imported-modules (source-module-closure '((guix build utils)))
+ #~(begin
+ (use-modules (guix build utils))
+
+ (let ((owner (getpwnam #$%transmission-daemon-user)))
+ (define (mkdir-p/perms directory perms)
+ (mkdir-p directory)
+ (chown directory (passwd:uid owner) (passwd:gid owner))
+ (chmod directory perms))
+
+ ;; Create the directories Transmission Daemon is configured to use
+ ;; and assign them suitable permissions.
+ (for-each (lambda (directory-specification)
+ (apply mkdir-p/perms directory-specification))
+ '(#$@(append
+ `((,config-dir #o750))
+ (if incomplete-dir-enabled
+ `((,incomplete-dir #o750))
+ '())
+ (if watch-dir-enabled
+ `((,watch-dir #o770))
+ '())))))
+
+ ;; Generate and activate the daemon's settings file, settings.json.
+ (activate-special-files
+ '((#$(string-append config-dir "/settings.json")
+ #$(transmission-daemon-computed-settings-file config))))))))
+
+(define transmission-daemon-service-type
+ (service-type
+ (name 'transmission)
+ (extensions
+ (list (service-extension shepherd-root-service-type
+ transmission-daemon-shepherd-service)
+ (service-extension account-service-type
+ (const %transmission-daemon-accounts))
+ (service-extension rottlog-service-type
+ (const %transmission-daemon-log-rotations))
+ (service-extension activation-service-type
+ transmission-daemon-activation)))
+ (default-value (transmission-daemon-configuration))
+ (description "Share files using the BitTorrent protocol.")))
+
+(define (generate-transmission-daemon-documentation)
+ (generate-documentation
+ `((transmission-daemon-configuration
+ ,transmission-daemon-configuration-fields))
+ 'transmission-daemon-configuration))
diff --git a/po/packages/POTFILES.in b/po/packages/POTFILES.in
index 9a178ed..398f9ad 100644
--- a/po/packages/POTFILES.in
+++ b/po/packages/POTFILES.in
@@ -59,5 +59,6 @@ gnu/packages/wordnet.scm
gnu/packages/xiph.scm
gnu/services/base.scm
gnu/services/certbot.scm
+gnu/services/file-sharing.scm
gnu/services/networking.scm
gnu/services/version-control.scm
diff --git a/tests/services/file-sharing.scm b/tests/services/file-sharing.scm
new file mode 100644
index 0000000..27bec57
--- /dev/null
+++ b/tests/services/file-sharing.scm
@@ -0,0 +1,59 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2020 Simon South <si...@simonsouth.net>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (tests services file-sharing)
+ #:use-module (gnu services file-sharing)
+ #:use-module (srfi srfi-64))
+
+;;; Tests for the (gnu services file-sharing) module.
+
+(test-begin "file-sharing")
+
+
+;;;
+;;; Transmission Daemon.
+;;;
+
+(define %transmission-salt-length 8)
+
+(define (valid-transmission-salt? salt)
+ (and (string? salt)
+ (eqv? (string-length salt) %transmission-salt-length)))
+
+(test-assert "transmission-random-salt"
+ (valid-transmission-salt? (transmission-random-salt)))
+
+(test-equal "transmission-password-hash, typical values"
+ "{ef6fba106cdef3aac64d1410090cae353cbecde53ceVVQO2"
+ (transmission-password-hash "transmission" "3ceVVQO2"))
+
+(test-equal "transmission-password-hash, empty password"
+ "{820f816515d8969d058d07a1de018650619ee7ffCp.I5SWg"
+ (transmission-password-hash "" "Cp.I5SWg"))
+
+(test-error "transmission-password-hash, salt value too short"
+ (transmission-password-hash
+ "transmission"
+ (make-string (- %transmission-salt-length 1) #\a)))
+
+(test-error "transmission-password-hash, salt value too long"
+ (transmission-password-hash
+ "transmission"
+ (make-string (+ %transmission-salt-length 1) #\a)))
+
+(test-end "file-sharing")
