services: Add a service for Jami.

* gnu/services/telephony.scm (string-or-computed-file?)
(string-list?, account-fingerprint-list?): New procedures.
(maybe-string-list, maybe-account-fingerprint-list)
(maybe-boolean, maybe-string, jami-account-list): New configuration field
types.
(serialize-string-list, serialize-boolean, serialize-string)
(jami-account, jami-account->alist, jami-configuration)
(jami-account-list?, jami-account-list-maybe): New procedures.
(%jami-accounts): New variable.
(jami-configuration->command-line-arguments): New procedure.
(jami-dbus-session-activation, jami-shepherd-services): New procedures.
(jami-service-type): New variable.
* gnu/build/jami-service.scm: New file.
* gnu/tests/data/jami-dummy-account.dat: Likewise.
* gnu/tests/telephony.scm: Likewise.
* gnu/local.mk (GNU_SYSTEM_MODULES): Register them.
* Makefile.am (SCM_TESTS): Register the test file.
(dist_patch_DATA): Register the new data file.
* doc/guix.texi (Telephony Services): Document it.

1 files changed, 587 insertions, 0 deletions

diff --git a/gnu/build/jami-service.scm b/gnu/build/jami-service.scm
new file mode 100644
index 0000000000..d44e87387d
--- /dev/null
+++ b/gnu/build/jami-service.scm
@@ -0,0 +1,587 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Maxim Cournoyer <maxim.cournoyer@gmail.com>
+;;;
+;;; 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/>.
+
+;;; Commentary:
+;;;
+;;; This module contains helpers used as part of the jami-service-type
+;;; definition.
+;;;
+;;; Code:
+
+(define-module (gnu build jami-service)
+  #:use-module (ice-9 format)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 peg)
+  #:use-module (ice-9 rdelim)
+  #:use-module (ice-9 regex)
+  #:use-module (rnrs io ports)
+  #:autoload (shepherd service) (fork+exec-command)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:export (account-fingerprint?
+            account-details->recutil
+            get-accounts
+            get-usernames
+            set-account-details
+            add-account
+            account->username
+            username->account
+            username->contacts
+            enable-account
+            disable-account
+
+            add-contact
+            remove-contact
+
+            set-all-moderators
+            set-moderator
+            username->all-moderators?
+            username->moderators
+
+            dbus-available-services
+            dbus-service-available?
+
+            %send-dbus-binary
+            %send-dbus-bus
+            %send-dbus-user
+            %send-dbus-group
+            %send-dbus-debug
+            send-dbus
+
+            with-retries))
+
+;;;
+;;; Utilities.
+;;;
+
+(define-syntax-rule (with-retries n delay body ...)
+  "Retry the code in BODY up to N times until it doesn't raise an exception
+nor return #f, else raise an error.  A delay of DELAY seconds is inserted
+before each retry."
+  (let loop ((attempts 0))
+    (catch #t
+      (lambda ()
+        (let ((result (begin body ...)))
+          (if (not result)
+              (error "failed attempt" attempts)
+              result)))
+      (lambda args
+        (if (< attempts n)
+            (begin
+              (sleep delay)             ;else wait and retry
+              (loop (+ 1 attempts)))
+            (error "maximum number of retry attempts reached"
+                   body ... args))))))
+
+(define (alist->list alist)
+  "Flatten ALIST into a list."
+  (append-map (match-lambda
+                (() '())
+                ((key . value)
+                 (list key value)))
+              alist))
+
+(define account-fingerprint-rx (make-regexp "[0-9A-f]{40}"))
+
+(define (account-fingerprint? val)
+  "A Jami account fingerprint is 40 characters long and only contains
+hexadecimal characters."
+  (and (string? val)
+       (regexp-exec account-fingerprint-rx val)))
+
+
+;;;
+;;; D-Bus reply parser.
+;;;
+
+(define (parse-dbus-reply reply)
+  "Return the parse tree of REPLY, a string returned by the 'dbus-send'
+command."
+  ;; Refer to 'man 1 dbus-send' for the grammar reference.  Note that the
+  ;; format of the replies doesn't match the format of the input, which is the
+  ;; one documented, but it gives an idea.  For an even better reference, see
+  ;; the `print_iter' procedure of the 'dbus-print-message.c' file from the
+  ;; 'dbus' package sources.
+  (define-peg-string-patterns
+    "contents <- header (item / container (item / container*)?)
+     item <-- WS type WS value NL
+     container <- array / dict / variant
+     array <-- array-start (item / container)* array-end
+     dict <-- array-start dict-entry* array-end
+     dict-entry <-- dict-entry-start item item dict-entry-end
+     variant <-- variant-start item
+     type <-- 'string' / 'int16' / 'uint16' / 'int32' / 'uint32' / 'int64' /
+              'uint64' / 'double' / 'byte' / 'boolean' / 'objpath'
+     value <-- (!NL .)* NL
+     header < (!NL .)* NL
+     variant-start < WS 'variant'
+     array-start < WS 'array [' NL
+     array-end < WS ']' NL
+     dict-entry-start < WS 'dict entry(' NL
+     dict-entry-end < WS ')' NL
+     DQ < '\"'
+     WS < ' '*
+     NL < '\n'*")
+
+  (peg:tree (match-pattern contents reply)))
+
+(define (strip-quotes text)
+  "Strip the leading and trailing double quotes (\") characters from TEXT."
+  (let* ((text* (if (string-prefix? "\"" text)
+                    (string-drop text 1)
+                    text))
+         (text** (if (string-suffix? "\"" text*)
+                     (string-drop-right text* 1)
+                     text*)))
+    text**))
+
+(define (deserialize-item item)
+  "Return the value described by the ITEM parse tree as a Guile object."
+  ;; Strings are printed wrapped in double quotes (see the print_iter
+  ;; procedure in dbus-print-message.c).
+  (match item
+    (('item ('type "string") ('value value))
+     (strip-quotes value))
+    (('item ('type "boolean") ('value value))
+     (if (string=? "true" value)
+         #t
+         #f))
+    (('item _ ('value value))
+     value)))
+
+(define (serialize-boolean bool)
+  "Return the serialized format expected by dbus-send for BOOL."
+  (format #f "boolean:~:[false~;true~]" bool))
+
+(define (dict->alist dict-parse-tree)
+  "Translate a dict parse tree to an alist."
+  (define (tuples->alist tuples)
+    (map (lambda (x) (apply cons x)) tuples))
+
+  (match dict-parse-tree
+    ('dict
+     '())
+    (('dict ('dict-entry keys values) ...)
+     (let ((keys* (map deserialize-item keys))
+           (values* (map deserialize-item values)))
+       (tuples->alist (zip keys* values*))))))
+
+(define (array->list array-parse-tree)
+  "Translate an array parse tree to a list."
+  (match array-parse-tree
+    ('array
+     '())
+    (('array items ...)
+     (map deserialize-item items))))
+
+
+;;;
+;;; Low-level, D-Bus-related procedures.
+;;;
+
+;;; The following parameters are used in the jami-service-type service
+;;; definition to conveniently customize the behavior of the send-dbus helper,
+;;; even when called indirectly.
+(define %send-dbus-binary (make-parameter "dbus-send"))
+(define %send-dbus-bus (make-parameter #f))
+(define %send-dbus-user (make-parameter #f))
+(define %send-dbus-group (make-parameter #f))
+(define %send-dbus-debug (make-parameter #f))
+
+(define* (send-dbus #:key service path interface method
+                    bus
+                    dbus-send
+                    user group
+                    timeout
+                    arguments)
+  "Return the response of DBUS-SEND, else raise an error.  Unless explicitly
+provided, DBUS-SEND takes the value of the %SEND-DBUS-BINARY parameter.  BUS
+can be used to specify the bus address, such as 'unix:path=/var/run/jami/bus'.
+Alternatively, the %SEND-DBUS-BUS parameter can be used.  ARGUMENTS can be
+used to pass input values to a D-Bus method call.  TIMEOUT is the amount of
+time to wait for a reply in milliseconds before giving up with an error.  USER
+and GROUP allow choosing under which user/group the DBUS-SEND command is
+executed.  Alternatively, the %SEND-DBUS-USER and %SEND-DBUS-GROUP parameters
+can be used instead."
+  (let* ((command `(,(if dbus-send
+                         dbus-send
+                         (%send-dbus-binary))
+                    ,@(if (or bus (%send-dbus-bus))
+                          (list (string-append "--bus="
+                                               (or bus (%send-dbus-bus))))
+                          '())
+                    "--print-reply"
+                    ,@(if timeout
+                          (list (format #f "--reply-timeout=~d" timeout))
+                          '())
+                    ,(string-append "--dest=" service) ;e.g., cx.ring.Ring
+                    ,path            ;e.g., /cx/ring/Ring/ConfigurationManager
+                    ,(string-append interface "." method)
+                    ,@(or arguments '())))
+         (temp-port (mkstemp! (string-copy "/tmp/dbus-send-output-XXXXXXX")))
+         (temp-file (port-filename temp-port)))
+    (dynamic-wind
+      (lambda ()
+        (let* ((uid (or (and=> (or user (%send-dbus-user))
+                               (compose passwd:uid getpwnam)) -1))
+               (gid (or (and=> (or group (%send-dbus-group))
+                               (compose group:gid getgrnam)) -1)))
+          (chown temp-port uid gid)))
+      (lambda ()
+        (let ((pid (fork+exec-command command
+                                      #:user (or user (%send-dbus-user))
+                                      #:group (or group (%send-dbus-group))
+                                      #:log-file temp-file)))
+          (match (waitpid pid)
+            ((_ . status)
+             (let ((exit-status (status:exit-val status))
+                   (output (call-with-port temp-port get-string-all)))
+               (if (= 0 exit-status)
+                   output
+                   (error "the send-dbus command exited with: "
+                          command exit-status output)))))))
+      (lambda ()
+        (false-if-exception (delete-file temp-file))))))
+
+(define (parse-account-ids reply)
+  "Return the Jami account IDs from REPLY, which is assumed to be the output
+of the Jami D-Bus `getAccountList' method."
+  (array->list (parse-dbus-reply reply)))
+
+(define (parse-account-details reply)
+  "Parse REPLY, which is assumed to be the output of the Jami D-Bus
+`getAccountDetails' method, and return its content as an alist."
+  (dict->alist (parse-dbus-reply reply)))
+
+(define (parse-contacts reply)
+  "Parse REPLY, which is assumed to be the output of the Jamid D-Bus
+`getContacts' method, and return its content as an alist."
+  (match (parse-dbus-reply reply)
+    ('array
+     '())
+    (('array dicts ...)
+     (map dict->alist dicts))))
+
+
+;;;
+;;; Higher-level, D-Bus-related procedures.
+;;;
+
+(define (validate-fingerprint fingerprint)
+  "Validate that fingerprint is 40 characters long."
+  (unless (account-fingerprint? fingerprint)
+    (error "Account fingerprint is not valid:" fingerprint)))
+
+(define (dbus-available-services)
+  "Return the list of available (acquired) D-Bus services."
+  (let ((reply (parse-dbus-reply
+                (send-dbus #:service "org.freedesktop.DBus"
+                           #:path "/org/freedesktop/DBus"
+                           #:interface "org.freedesktop.DBus"
+                           #:method "ListNames"))))
+    ;; Remove entries such as ":1.7".
+    (remove (cut string-prefix? ":" <>)
+            (array->list reply))))
+
+(define (dbus-service-available? service)
+  "Predicate to check for the D-Bus SERVICE availability."
+  (member service (dbus-available-services)))
+
+(define* (send-dbus/configuration-manager #:key method arguments timeout)
+  "Query the Jami D-Bus ConfigurationManager service."
+  (send-dbus #:service "cx.ring.Ring"
+             #:path "/cx/ring/Ring/ConfigurationManager"
+             #:interface "cx.ring.Ring.ConfigurationManager"
+             #:method method
+             #:arguments arguments
+             #:timeout timeout))
+
+;;; The following methods are for internal use; they make use of the account
+;;; ID, an implementation detail of Jami the user should not need to be
+;;; concerned with.
+(define (get-account-ids)
+  "Return the available Jami account identifiers (IDs).  Account IDs are an
+implementation detail used to identify the accounts in Jami."
+  (parse-account-ids
+   (send-dbus/configuration-manager #:method "getAccountList")))
+
+(define (id->account-details id)
+  "Retrieve the account data associated with the given account ID."
+  (parse-account-details
+   (send-dbus/configuration-manager
+    #:method "getAccountDetails"
+    #:arguments (list (string-append "string:" id)))))
+
+(define (id->volatile-account-details id)
+  "Retrieve the account data associated with the given account ID."
+  (parse-account-details
+   (send-dbus/configuration-manager
+    #:method "getVolatileAccountDetails"
+    #:arguments (list (string-append "string:" id)))))
+
+(define (id->account id)
+  "Retrieve the complete account data associated with the given account ID."
+  (append (id->volatile-account-details id)
+          (id->account-details id)))
+
+(define %username-to-id-cache #f)
+
+(define (invalidate-username-to-id-cache!)
+  (set! %username-to-id-cache #f))
+
+(define (username->id username)
+  "Return the first account ID corresponding to USERNAME."
+  (unless (assoc-ref %username-to-id-cache username)
+    (set! %username-to-id-cache
+          (append-map
+           (lambda (id)
+             (let* ((account (id->account id))
+                    (username (assoc-ref account "Account.username"))
+                    (registered-name (assoc-ref account
+                                                "Account.registeredName")))
+               `(,@(if username
+                       (list (cons username id))
+                       '())
+                 ,@(if registered-name
+                       (list (cons registered-name id))
+                       '()))))
+           (get-account-ids))))
+  (or (assoc-ref %username-to-id-cache username)
+      (let ((message (format #f "Could not retrieve a local account ID\
+ for ~:[username~;fingerprint~]" (account-fingerprint? username))))
+        (error message username))))
+
+(define (account->username account)
+  "Return USERNAME, the registered username associated with ACCOUNT, else its
+public key fingerprint."
+  (or (assoc-ref account "Account.registeredName")
+      (assoc-ref account "Account.username")))
+
+(define (id->username id)
+  "Return USERNAME, the registered username associated with ID, else its
+public key fingerprint, else #f."
+  (account->username (id->account id)))
+
+(define (get-accounts)
+  "Return the list of all accounts, as a list of alists."
+  (map id->account (get-account-ids)))
+
+(define (get-usernames)
+  "Return the list of the usernames associated with the present accounts."
+  (map account->username (get-accounts)))
+
+(define (username->account username)
+  "Return the first account associated with USERNAME, else #f.
+USERNAME can be either the account 40 characters public key fingerprint or a
+registered username."
+  (find (lambda (account)
+          (member username
+                  (list (assoc-ref account "Account.username")
+                        (assoc-ref account "Account.registeredName"))))
+        (get-accounts)))
+
+(define (add-account archive)
+  "Import the Jami account ARCHIVE and return its account ID.  The archive
+should *not* be encrypted with a password.  Return the username associated
+with the account."
+  (invalidate-username-to-id-cache!)
+  (let ((reply (send-dbus/configuration-manager
+                #:method "addAccount"
+                #:arguments (list (string-append
+                                   "dict:string:string:Account.archivePath,"
+                                   archive
+                                   ",Account.type,RING")))))
+    ;; The account information takes some time to be populated.
+    (let ((id (deserialize-item (parse-dbus-reply reply))))
+      (with-retries 20 1
+        (let ((username (id->username id)))
+          (if (string-null? username)
+              #f
+              username))))))
+
+(define (remove-account username)
+  "Delete the Jami account associated with USERNAME, the account 40 characters
+fingerprint or a registered username."
+  (let ((id (username->id username)))
+    (send-dbus/configuration-manager
+     #:method "removeAccount"
+     #:arguments (list (string-append "string:" id))))
+  (invalidate-username-to-id-cache!))
+
+(define* (username->contacts username)
+  "Return the contacts associated with the account of USERNAME as two values;
+the first one being the regular contacts and the second one the banned
+contacts.  USERNAME can be either the account 40 characters public key
+fingerprint or a registered username.  The contacts returned are represented
+using their 40 characters fingerprint."
+  (let* ((id (username->id username))
+         (reply (send-dbus/configuration-manager
+                 #:method "getContacts"
+                 #:arguments (list (string-append "string:" id))))
+         (all-contacts (parse-contacts reply))
+         (banned? (lambda (contact)
+                    (and=> (assoc-ref contact "banned")
+                           (cut string=? "true" <>))))
+         (banned (filter banned? all-contacts))
+         (not-banned (filter (negate banned?) all-contacts))
+         (fingerprint (cut assoc-ref <> "id")))
+    (values (map fingerprint not-banned)
+            (map fingerprint banned))))
+
+(define* (remove-contact contact username #:key ban?)
+  "Remove CONTACT, the 40 characters public key fingerprint of a contact, from
+the account associated with USERNAME (either a fingerprint or a registered
+username).  When BAN? is true, also mark the contact as banned."
+  (validate-fingerprint contact)
+  (let ((id (username->id username)))
+    (send-dbus/configuration-manager
+     #:method "removeContact"
+     #:arguments (list (string-append "string:" id)
+                       (string-append "string:" contact)
+                       (serialize-boolean ban?)))))
+
+(define (add-contact contact username)
+  "Add CONTACT, the 40 characters public key fingerprint of a contact, to the
+account of USERNAME (either a fingerprint or a registered username)."
+  (validate-fingerprint contact)
+  (let ((id (username->id username)))
+    (send-dbus/configuration-manager
+     #:method "addContact"
+     #:arguments (list (string-append "string:" id)
+                       (string-append "string:" contact)))))
+
+(define* (set-account-details details username #:key timeout)
+  "Set DETAILS, an alist containing the key value pairs to set for the account
+of USERNAME, a registered username or account fingerprint.  The value of the
+parameters not provided are unchanged.  TIMEOUT is a value in milliseconds to
+pass to the `send-dbus/configuration-manager' procedure."
+  (let* ((id (username->id username))
+         (current-details (id->account-details id))
+         (updated-details (map (match-lambda
+                                 ((key . value)
+                                  (or (and=> (assoc-ref details key)
+                                             (cut cons key <>))
+                                      (cons key value))))
+                               current-details))
+         ;; dbus-send does not permit sending null strings (it throws a
+         ;; "malformed dictionary" error).  Luckily they seem to have the
+         ;; semantic of "default account value" in Jami; so simply drop them.
+         (updated-details* (remove (match-lambda
+                                     ((_ . value)
+                                      (string-null? value)))
+                                   updated-details)))
+    (send-dbus/configuration-manager
+     #:timeout timeout
+     #:method "setAccountDetails"
+     #:arguments
+     (list (string-append "string:" id)
+           (string-append "dict:string:string:"
+                          (string-join (alist->list updated-details*)
+                                       ","))))))
+
+(define (set-all-moderators enabled? username)
+  "Set the 'AllModerators' property to enabled? for the account of USERNAME, a
+registered username or account fingerprint."
+  (let ((id (username->id username)))
+    (send-dbus/configuration-manager
+     #:method "setAllModerators"
+     #:arguments
+     (list (string-append "string:" id)
+           (serialize-boolean enabled?)))))
+
+(define (username->all-moderators? username)
+  "Return the 'AllModerators' property for the account of USERNAME, a
+registered username or account fingerprint."
+  (let* ((id (username->id username))
+         (reply (send-dbus/configuration-manager
+                 #:method "isAllModerators"
+                 #:arguments
+                 (list (string-append "string:" id)))))
+    (deserialize-item (parse-dbus-reply reply))))
+
+(define (username->moderators username)
+  "Return the moderators for the account of USERNAME, a registered username or
+account fingerprint."
+  (let* ((id (username->id username))
+         (reply (send-dbus/configuration-manager
+                 #:method "getDefaultModerators"
+                 #:arguments
+                 (list (string-append "string:" id)))))
+    (array->list (parse-dbus-reply reply))))
+
+(define (set-moderator contact enabled? username)
+  "Set the moderator flag to ENABLED? for CONTACT, the 40 characters public
+key fingerprint of a contact for the account of USERNAME, a registered
+username or account fingerprint."
+  (validate-fingerprint contact)
+  (let* ((id (username->id username)))
+    (send-dbus/configuration-manager #:method "setDefaultModerator"
+                                     #:arguments
+                                     (list (string-append "string:" id)
+                                           (string-append "string:" contact)
+                                           (serialize-boolean enabled?)))))
+
+(define (disable-account username)
+  "Disable the account known by USERNAME, a registered username or account
+fingerprint."
+  (set-account-details '(("Account.enable" . "false")) username
+                       ;; Waiting for the reply on this command takes a very
+                       ;; long time that trips the default D-Bus timeout value
+                       ;; (25 s), for some reason.
+                        #:timeout 60000))
+
+(define (enable-account username)
+  "Enable the account known by USERNAME, a registered username or account
+fingerprint."
+  (set-account-details '(("Account.enable" . "true")) username))
+
+
+;;;
+;;; Presentation procedures.
+;;;
+
+(define (.->_ text)
+  "Map each period character to underscore characters."
+  (string-map (match-lambda
+                (#\. #\_)
+                (c c))
+              text))
+
+(define (account-details->recutil account-details)
+  "Serialize the account-details alist into a recutil string.  Period
+characters in the keys are normalized to underscore to meet Recutils' format
+requirements."
+  (define (pair->recutil-property pair)
+    (match pair
+      ((key . value)
+       (string-append (.->_ key) ": " value))))
+
+  (define sorted-account-details
+    ;; Have the account username, display name and alias appear first, for
+    ;; convenience.
+    (let ((first-items '("Account.username"
+                         "Account.displayName"
+                         "Account.alias")))
+      (append (map (cut assoc <> account-details) first-items)
+              (fold alist-delete account-details first-items))))
+
+  (string-join (map pair->recutil-property sorted-account-details) "\n"))
+
+;; Local Variables:
+;; eval: (put 'with-retries 'scheme-indent-function 2)
+;; End: