[bug#37412] [PATCH 2/2] services: Add the Guix Data Service.

[Christopher Baines <mail@cbaines.net>]

* gnu/services/guix.scm: New file.
* gnu/tests/guix.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add both new files.
* doc/guix.texi (Guix Services): New section documenting the Guix Data
Service.
---
 doc/guix.texi         |  52 +++++++++++
 gnu/local.mk          |   2 +
 gnu/services/guix.scm | 212 ++++++++++++++++++++++++++++++++++++++++++
 gnu/tests/guix.scm    | 173 ++++++++++++++++++++++++++++++++++
 4 files changed, 439 insertions(+)
 create mode 100644 gnu/services/guix.scm
 create mode 100644 gnu/tests/guix.scm

diff --git a/doc/guix.texi b/doc/guix.texi
index 39d4b865f6..24da18ea13 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -11657,6 +11657,7 @@ declaration.
 * Virtualization Services::     Virtualization services.
 * Version Control Services::    Providing remote access to Git repositories.
 * Game Services::               Game servers.
+* Guix Services::               Services relating specifically to Guix.
 * Miscellaneous Services::      Other services.
 @end menu
 
@@ -24167,6 +24168,57 @@ The port to bind the server to.
 @end table
 @end deftp
 
+
+@node Guix Services
+@subsection Guix Services
+
+@subsubheading Guix Data Service
+The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
+and provides data about GNU Guix.  This includes information about
+packages, derivations and lint warnings.
+
+The data is stored in a PostgreSQL database, and available through a web
+interface.
+
+@defvar {Scheme Variable} guix-data-service-type
+Service type for the Guix Data Service.  Its value must be a
+@code{guix-data-service-configuration} object.  The service optionally
+extends the getmail service, as the guix-commits mailing list is used to
+find out about changes in the Guix git repository.
+@end defvar
+
+@deftp {Data Type} guix-data-service-configuration
+Data type representing the configuration of the Guix Data Service.
+
+@table @asis
+@item @code{package} (default: @code{guix-data-service})
+The Guix Data Service package to use.
+
+@item @code{user} (default: @code{"guix-data-service"})
+The system user to run the service as.
+
+@item @code{group} (default: @code{"guix-data-service"})
+The system group to run the service as.
+
+@item @code{port} (default: @code{8765})
+The port to bind the web service to.
+
+@item @code{host} (default: @code{"127.0.0.1"})
+The host to bind the web service to.
+
+@item @code{getmail-idle-mailboxes} (default: @code{#f})
+If set, this is the list of mailboxes that the getmail service will be
+configured to listen to.
+
+@item @code{commits-getmail-retriever-configuration} (default: @code{#f})
+If set, this is the @code{getmail-retriever-configuration} object with
+which to configure getmail to fetch mail from the guix-commits mailing
+list.
+
+@end table
+@end deftp
+
+
 @node Miscellaneous Services
 @subsection Miscellaneous Services
 
diff --git a/gnu/local.mk b/gnu/local.mk
index 3f32b9cbf2..b30afdd585 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -532,6 +532,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/services/authentication.scm		\
   %D%/services/games.scm			\
   %D%/services/getmail.scm				\
+  %D%/services/guix.scm			\
   %D%/services/kerberos.scm			\
   %D%/services/lirc.scm				\
   %D%/services/virtualization.scm		\
@@ -596,6 +597,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/tests/desktop.scm				\
   %D%/tests/dict.scm				\
   %D%/tests/docker.scm				\
+  %D%/tests/guix.scm				\
   %D%/tests/monitoring.scm                      \
   %D%/tests/nfs.scm				\
   %D%/tests/install.scm				\
diff --git a/gnu/services/guix.scm b/gnu/services/guix.scm
new file mode 100644
index 0000000000..0f0fad39b0
--- /dev/null
+++ b/gnu/services/guix.scm
@@ -0,0 +1,212 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2019 Christopher Baines <mail@cbaines.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 guix)
+  #:use-module (ice-9 match)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:use-module ((gnu packages base)
+                #:select (glibc-utf8-locales))
+  #:use-module (gnu packages admin)
+  #:use-module (gnu packages web)
+  #:use-module (gnu services)
+  #:use-module (gnu services base)
+  #:use-module (gnu services admin)
+  #:use-module (gnu services shepherd)
+  #:use-module (gnu services getmail)
+  #:use-module (gnu system shadow)
+  #:export (<guix-data-service-configuration>
+            guix-data-service-configuration
+            guix-data-service-configuration?
+            guix-data-service-package
+            guix-data-service-user
+            guix-data-service-group
+            guix-data-service-port
+            guix-data-service-host
+            guix-data-service-getmail-idle-mailboxes
+            guix-data-service-commits-getmail-retriever-configuration
+
+            guix-data-service-type))
+
+;;;; Commentary:
+;;;
+;;; This module implements a service that to run instances of the Guix Data
+;;; Service, which provides data about Guix over time.
+;;;
+;;;; Code:
+
+(define-record-type* <guix-data-service-configuration>
+  guix-data-service-configuration make-guix-data-service-configuration
+  guix-data-service-configuration?
+  (package          guix-data-service-package
+                    (default guix-data-service))
+  (user             guix-data-service-configuration-user
+                    (default "guix-data-service"))
+  (group            guix-data-service-configuration-group
+                    (default "guix-data-service"))
+  (port             guix-data-service-port
+                    (default 8765))
+  (host             guix-data-service-host
+                    (default "127.0.0.1"))
+  (getmail-idle-mailboxes
+   guix-data-service-getmail-idle-mailboxes
+   (default #f))
+  (commits-getmail-retriever-configuration
+   guix-data-service-commits-getmail-retriever-configuration
+   (default #f)))
+
+(define (guix-data-service-profile-packages config)
+  "Return the guix-data-service package, this will populate the
+ca-certificates.crt file in the system profile."
+  (list
+   (guix-data-service-package config)))
+
+(define (guix-data-service-shepherd-services config)
+  (match-record config <guix-data-service-configuration>
+    (package user group port host)
+    (list
+     (shepherd-service
+      (documentation "Guix Data Service web server")
+      (provision '(guix-data-service))
+      (requirement '(postgres networking))
+      (start #~(make-forkexec-constructor
+                (list #$(file-append package
+                                     "/bin/guix-data-service")
+                      "--pid-file=/var/run/guix-data-service/pid"
+                      #$(string-append "--port=" (number->string port))
+                      #$(string-append "--host=" host)
+                      ;; Perform any database migrations when the
+                      ;; service is started
+                      "--update-database")
+
+                #:user #$user
+                #:group #$group
+                #:pid-file "/var/run/guix-data-service/pid"
+                ;; Allow time for migrations to run
+                #:pid-file-timeout 60
+                #:environment-variables
+                `(,(string-append
+                    "GUIX_LOCPATH=" #$glibc-utf8-locales "/lib/locale")
+                  "LC_ALL=en_US.utf8")
+                #:log-file "/var/log/guix-data-service/web.log"))
+      (stop #~(make-kill-destructor)))
+
+     (shepherd-service
+      (documentation "Guix Data Service process jobs")
+      (provision '(guix-data-service-process-jobs))
+      (requirement '(postgres
+                     networking
+                     ;; Require guix-data-service, as that the database
+                     ;; migrations are handled through this service
+                     guix-data-service))
+      (start #~(make-forkexec-constructor
+                (list
+                 #$(file-append package
+                                "/bin/guix-data-service-process-jobs"))
+                #:user #$user
+                #:group #$group
+                #:environment-variables
+                `("HOME=/var/lib/guix-data-service"
+                  "GIT_SSL_CAINFO=/etc/ssl/certs/ca-certificates.crt"
+                  ,(string-append
+                    "GUIX_LOCPATH=" #$glibc-utf8-locales "/lib/locale")
+                  "LC_ALL=en_US.utf8")
+                #:log-file "/var/log/guix-data-service/process-jobs.log"))
+      (stop #~(make-kill-destructor))))))
+
+(define (guix-data-service-activation config)
+  #~(begin
+      (use-modules (guix build utils))
+
+      (define %user (getpw "guix-data-service"))
+
+      (chmod "/var/lib/guix-data-service" #o755)
+
+      (mkdir-p "/var/log/guix-data-service")
+
+      ;; Allow writing the PID file
+      (mkdir-p "/var/run/guix-data-service")
+      (chown "/var/run/guix-data-service"
+             (passwd:uid %user)
+             (passwd:gid %user))))
+
+(define (guix-data-service-account config)
+  (match-record config <guix-data-service-configuration>
+    (user group)
+    (list (user-group
+           (name group)
+           (system? #t))
+          (user-account
+           (name user)
+           (group group)
+           (system? #t)
+           (comment "Guix Data Service user")
+           (home-directory "/var/lib/guix-data-service")
+           (shell (file-append shadow "/sbin/nologin"))))))
+
+(define (guix-data-service-getmail-configuration config)
+  (match config
+    (($ <guix-data-service-configuration> package user group
+                                          port host
+                                          #f #f)
+     '())
+    (($ <guix-data-service-configuration> package user group
+                                          port host
+                                          getmail-idle-mailboxes
+                                          commits-getmail-retriever-configuration)
+     (list
+      (getmail-configuration
+       (name 'guix-data-service)
+       (user user)
+       (group group)
+       (directory "/var/lib/getmail/guix-data-service")
+       (rcfile
+        (getmail-configuration-file
+         (retriever commits-getmail-retriever-configuration)
+         (destination
+          (getmail-destination-configuration
+           (type "MDA_external")
+           (path (file-append
+                  package
+                  "/bin/guix-data-service-process-branch-updated-email"))))
+         (options
+          (getmail-options-configuration
+           (read-all #f)
+           (delivered-to #f)
+           (received #f)))))
+       (idle getmail-idle-mailboxes))))))
+
+(define guix-data-service-type
+  (service-type
+   (name 'guix-data-service)
+   (extensions
+    (list
+     (service-extension profile-service-type
+                        guix-data-service-profile-packages)
+     (service-extension shepherd-root-service-type
+                        guix-data-service-shepherd-services)
+     (service-extension activation-service-type
+                        guix-data-service-activation)
+     (service-extension account-service-type
+                        guix-data-service-account)
+     (service-extension getmail-service-type
+                        guix-data-service-getmail-configuration)))
+   (default-value
+     (guix-data-service-configuration))
+   (description
+    "Run an instance of the Guix Data Service.")))
diff --git a/gnu/tests/guix.scm b/gnu/tests/guix.scm
new file mode 100644
index 0000000000..6139e31cf0
--- /dev/null
+++ b/gnu/tests/guix.scm
@@ -0,0 +1,173 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2019 Christopher Baines <mail@cbaines.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 tests guix)
+  #:use-module (gnu tests)
+  #:use-module (gnu system)
+  #:use-module (gnu system file-systems)
+  #:use-module (gnu system shadow)
+  #:use-module (gnu system vm)
+  #:use-module (gnu services)
+  #:use-module (gnu services guix)
+  #:use-module (gnu services databases)
+  #:use-module (gnu services shepherd)
+  #:use-module (gnu services networking)
+  #:use-module (gnu packages databases)
+  #:use-module (guix packages)
+  #:use-module (guix modules)
+  #:use-module (guix records)
+  #:use-module (guix gexp)
+  #:use-module (guix store)
+  #:use-module (guix utils)
+  #:use-module (ice-9 match)
+  #:export (%test-guix-data-service))
+
+\f
+;;;
+;;; Guix Data Service
+;;;
+
+(define guix-data-service-initial-database-setup-service
+  (let ((user "guix_data_service")
+        (name "guix_data_service"))
+    (define start-gexp
+      #~(lambda ()
+          (let ((pid (primitive-fork))
+                (postgres (getpwnam "postgres")))
+            (if (eq? pid 0)
+                (dynamic-wind
+                  (const #t)
+                  (lambda ()
+                    (setgid (passwd:gid postgres))
+                    (setuid (passwd:uid postgres))
+                    (primitive-exit
+                     (if (and
+                          (zero?
+                           (system* #$(file-append postgresql "/bin/createuser")
+                                    #$user))
+                          (zero?
+                           (system* #$(file-append postgresql "/bin/createdb")
+                                    "-O" #$user #$name)))
+                         0
+                         1)))
+                  (lambda ()
+                    (primitive-exit 1)))
+                (zero? (cdr (waitpid pid)))))))
+
+    (shepherd-service
+     (requirement '(postgres))
+     (provision '(guix-data-service-initial-database-setup))
+     (start start-gexp)
+     (stop #~(const #f))
+     (respawn? #f)
+     (one-shot? #t)
+     (documentation "Setup Guix Data Service database."))))
+
+(define %guix-data-service-os
+  (simple-operating-system
+   (service dhcp-client-service-type)
+   (service postgresql-service-type
+            (postgresql-configuration
+             (config-file
+              (postgresql-config-file
+               (hba-file
+                (plain-file "pg_hba.conf"
+                            "
+local	all	all			trust
+host	all	all	127.0.0.1/32 	trust
+host	all	all	::1/128 	trust"))))))
+   (service guix-data-service-type
+            (guix-data-service-configuration
+             (host "0.0.0.0")))
+   (simple-service 'guix-data-service-database-setup
+                   shepherd-root-service-type
+                   (list guix-data-service-initial-database-setup-service))))
+
+(define (run-guix-data-service-test)
+  (define os
+    (marionette-operating-system
+     %guix-data-service-os
+     #:imported-modules '((gnu services herd)
+                          (guix combinators))))
+
+  (define forwarded-port 8080)
+
+  (define vm
+    (virtual-machine
+     (operating-system os)
+     (memory-size 1024)
+     (port-forwardings `((,forwarded-port . 8765)))))
+
+  (define test
+    (with-imported-modules '((gnu build marionette))
+      #~(begin
+          (use-modules (srfi srfi-11) (srfi srfi-64)
+                       (gnu build marionette)
+                       (web uri)
+                       (web client)
+                       (web response))
+
+          (define marionette
+            (make-marionette (list #$vm)))
+
+          (mkdir #$output)
+          (chdir #$output)
+
+          (test-begin "guix-data-service")
+
+          (test-assert "service running"
+            (marionette-eval
+             '(begin
+                (use-modules (gnu services herd))
+                (match (start-service 'guix-data-service)
+                  (#f #f)
+                  (('service response-parts ...)
+                   (match (assq-ref response-parts 'running)
+                     ((pid) (number? pid))))))
+             marionette))
+
+          (test-assert "process jobs service running"
+            (marionette-eval
+             '(begin
+                (use-modules (gnu services herd))
+                (match (start-service 'guix-data-service-process-jobs)
+                  (#f #f)
+                  (('service response-parts ...)
+                   (match (assq-ref response-parts 'running)
+                     ((pid) (number? pid))))))
+             marionette))
+
+          (test-equal "http-get"
+            200
+            (let-values
+                (((response text)
+                  (http-get #$(simple-format
+                               #f "http://localhost:~A/healthcheck" forwarded-port)
+                            #:decode-body? #t)))
+              (response-code response)))
+
+          (test-end)
+          (exit (= (test-runner-fail-count (test-runner-current)) 0)))))
+
+  (gexp->derivation "guix-data-service-test" test))
+
+(define %test-guix-data-service
+  (system-test
+   (name "guix-data-service")
+   (description "Connect to a running Guix Data Service.")
+   (value (run-guix-data-service-test))))
-- 
2.23.0