Merge pull request #295 from yast/dbus-activation

Use D-Bus activation instead of explicit service starting

README.md

@@ -101,8 +101,11 @@ $ make devel-install
 $ cd -
 ~~~
 
-* Start the services: beware that D-Installer must run as root (like YaST does) to do hardware probing, partition the disks, install the software and so on.
-
+* Start the services:
+    * beware that D-Installer must run as root (like YaST does) to do
+      hardware probing, partition the disks, install the software and so on.
+    * Note that `setup.sh` sets up D-Bus activation so starting manually is
+      only needed when you prefer to see the log output upfront.
 ~~~
 $ cd service
 $ sudo bundle exec bin/d-installer

service/.editorconfig

@@ -4,6 +4,6 @@
 root = true
 
 # 2 space indentation
-[*.rb]
+[{*.rb,bin/d-installer}]
 indent_style = space
 indent_size = 2

service/bin/d-installer

@@ -26,9 +26,27 @@
 $LOAD_PATH.unshift File.expand_path("../lib", __dir__)
 
 require "rubygems"
-require "bundler/setup"
+# find Gemfile when D-Bus activates a git checkout
+Dir.chdir(__dir__) do
+  require "bundler/setup"
+end
 require "dinstaller/dbus/service_runner"
 
+# Set up a {Logger} suitable either for terminal (started manually)
+# or syslog (D-Bus activated)
+# @return [Logger]
+def logger_for(name)
+  if $stdout.tty?
+    formatter = Logger::Formatter.new # the default
+  else
+    # going via syslog which will provide time and progname already
+    formatter = ->(severity, _time, _progname, msg) { "#{severity}: #{msg}\n" }
+    $stdout.sync = true
+  end
+
+  Logger.new($stdout, progname: name.to_s, formatter: formatter)
+end
+
 # Runs the service with the given name
 #
 # @param name [Symbol] Service name
@@ -38,32 +56,51 @@ def start_service(name)
   module_y2dir = File.expand_path("../lib/dinstaller/dbus/y2dir/#{name}", __dir__)
   ENV["Y2DIR"] = "#{module_y2dir}:#{general_y2dir}"
 
-  logger = Logger.new($stdout, progname: name.to_s)
-  service_runner = DInstaller::DBus::ServiceRunner.new(name, logger: logger)
+  service_runner = DInstaller::DBus::ServiceRunner.new(name, logger: logger_for(name))
   service_runner.run
 end
 
 ORDERED_SERVICES = [:questions, :language, :software, :storage, :users, :manager].freeze
 
-# Starts all the services
+# Normally the services are started by D-Bus activation.
+# This starts all the services sequentially without relying on that.
+# This is useful during development to have their log output on the terminal,
+# not mixed with other syslog/journal messages.
+# The downside is relying on an arbitrary delay, and a manually maintained ordering.
 #
-# @return [Array<Integer>] PIDs
+# @return [void]
 # @see ORDERED_SERVICES
 def start_all_services
   ORDERED_SERVICES.map do |name|
+    puts "Starting #{name}:"
     fork { exec("#{__FILE__} #{name}") }
-    # TODO: implement a better mechanism to check whether the service is running
-    sleep(1)
+    sleep(7)
   end
 end
 
 if ARGV.empty?
-  pids = start_all_services
+  start_all_services
   Signal.trap("SIGINT") do
     puts "Stopping all services..."
     exit
   end
   Process.wait
+elsif ["-h", "--help"].include?(ARGV[0])
+  me = $PROGRAM_NAME
+  puts "Usage:"
+  puts "#{me} -h|--help"
+  puts "#{me} -s|--status"
+  puts "#{me} -k|--kill"
+  puts "#{me} #{ORDERED_SERVICES.sort.join("|")}"
+elsif ["-s", "--status"].include?(ARGV[0])
+  # The .[a-z] ensures matching the forked processes
+  # which can be distinguished by having a non-option argument
+  system "pgrep -fl bin/d-installer.[a-z]"
+  # busctl is prettier but will find nothing until the service files are installed,
+  # hence the pgrep above
+  system "busctl | grep -E '^NAME|DInstaller'"
+elsif ["-k", "--kill"].include?(ARGV[0])
+  system "pkill -f bin/d-installer.[a-z]"
 else
   name = ARGV[0]
   Signal.trap("SIGINT") do

service/package/gem2rpm.yml

@@ -15,10 +15,13 @@
 # ## used by gem2rpm
 :post_install: |-
   install -D -m 0644 %{buildroot}%{gem_base}/gems/%{mod_full_name}/share/dbus.conf %{buildroot}%{_datadir}/dbus-1/system.d/org.opensuse.DInstaller.conf
+  install --directory %{buildroot}%{_datadir}/dbus-1/system-services
+  install -m 0644 --target-directory=%{buildroot}%{_datadir}/dbus-1/system-services %{buildroot}%{gem_base}/gems/%{mod_full_name}/share/org.opensuse.DInstaller*.service
   install -D -m 0644 %{buildroot}%{gem_base}/gems/%{mod_full_name}/share/systemd.service %{buildroot}%{_unitdir}/d-installer.service
   install -D -m 0644 %{buildroot}%{gem_base}/gems/%{mod_full_name}/etc/d-installer.yaml %{buildroot}%{_sysconfdir}/d-installer.yaml
 # ## used by gem_packages
 :main:
   :filelist: "%{_datadir}/dbus-1/system.d/org.opensuse.DInstaller.conf\n
+    %{_datadir}/dbus-1/system-services/org.opensuse.DInstaller*.service\n
     %{_unitdir}/d-installer.service\n
     %{_sysconfdir}/d-installer.yaml\n"

service/share/org.opensuse.DInstaller.Language.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=org.opensuse.DInstaller.Language
+Exec=/usr/bin/d-installer language
+User=root

service/share/org.opensuse.DInstaller.Questions.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=org.opensuse.DInstaller.Questions
+Exec=/usr/bin/d-installer questions
+User=root

service/share/org.opensuse.DInstaller.Software.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=org.opensuse.DInstaller.Software
+Exec=/usr/bin/d-installer software
+User=root

service/share/org.opensuse.DInstaller.Storage.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=org.opensuse.DInstaller.Storage
+Exec=/usr/bin/d-installer storage
+User=root

service/share/org.opensuse.DInstaller.Users.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=org.opensuse.DInstaller.Users
+Exec=/usr/bin/d-installer users
+User=root

service/share/org.opensuse.DInstaller.service

@@ -0,0 +1,5 @@
+[D-BUS Service]
+Name=org.opensuse.DInstaller
+Exec=/usr/bin/d-installer manager
+User=root
+SystemdService=d-installer.service

service/share/systemd.service

@@ -6,7 +6,7 @@ After=network-online.target
 [Service]
 Type=dbus
 BusName=org.opensuse.DInstaller
-ExecStart=/usr/bin/d-installer
+ExecStart=/usr/bin/d-installer manager
 User=root
 TimeoutStopSec=5
 

setup.sh

@@ -8,14 +8,36 @@ sudo zypper --non-interactive install gcc gcc-c++ make openssl-devel ruby-devel
 
 sudo systemctl start cockpit
 
+# Like "sed -e $1 < $2 > $3" but $3 is a system file owned by root
+sudosed() {
+  echo "$2 -> $3"
+  sed -e "$1" "$2" | sudo tee "$3" > /dev/null
+}
+
 # set up the d-installer service
-sudo cp service/share/dbus.conf /usr/share/dbus-1/system.d/org.opensuse.DInstaller.conf
+MYDIR=$(realpath $(dirname $0))
+sudo cp -v $MYDIR/service/share/dbus.conf /usr/share/dbus-1/system.d/org.opensuse.DInstaller.conf
+(
+  # D-Bus service activation
+  cd $MYDIR/service/share
+  DBUSDIR=/usr/share/dbus-1/system-services
+  for SVC in org.opensuse.DInstaller*.service; do
+    sudosed "s@\(Exec\)=/usr/bin/@\1=$MYDIR/service/bin/@" $SVC $DBUSDIR/$SVC
+  done
+  sudosed "s@\(ExecStart\)=/usr/bin/@\1=$MYDIR/service/bin/@" \
+          systemd.service /usr/lib/systemd/system/d-installer.service
+  sudo systemctl daemon-reload
+)
 cd service; bundle config set --local path 'vendor/bundle'; bundle install; cd -
 
 # set up the web UI
 cd web; make devel-install; cd -
-sudo ln -s `pwd`/web/dist /usr/share/cockpit/d-installer
+sudo ln -snf `pwd`/web/dist /usr/share/cockpit/d-installer
 
 # Start the installer
-echo -e "\nStart the d-installer service:\n  cd service; sudo bundle exec bin/d-installer\n"
-echo -e "Visit http://localhost:9090/cockpit/@localhost/d-installer/index.html"
+echo
+echo "D-Bus will start the services, see journalctl for their logs."
+echo "To start the services manually, logging to the terminal:"
+echo "  cd service; sudo bundle exec bin/d-installer"
+echo
+echo "Visit http://localhost:9090/cockpit/@localhost/d-installer/index.html"