restart YaST after upgrading the packages (bnc#942080)

to avoid using the old (removed) files

package/yast2-migration.changes

@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Tue Aug 18 07:58:27 UTC 2015 - lslezak@suse.cz
+
+- restart YaST after upgrading the packages to avoid using the old
+  (removed) files (bnc#942080)
+
 -------------------------------------------------------------------
 Fri Aug 14 07:37:00 UTC 2015 - lslezak@suse.cz
 

src/lib/migration/main_workflow.rb

@@ -27,6 +27,7 @@
 Yast.import "Report"
 
 require "migration/finish_dialog"
+require "migration/restarter"
 
 module Migration
   # The goal of the class is to provide main single entry point to start
@@ -67,7 +68,11 @@ def run
     private
 
     WORKFLOW_SEQUENCE = {
-      "ws_start"        => "create_backup",
+      "ws_start"        => "start",
+      "start"           => {
+        start:   "create_backup",
+        restart: "finish_dialog"
+      },
       "create_backup"   => {
         next: "repositories"
       },
@@ -83,7 +88,10 @@ def run
         next: "perform_update"
       },
       "perform_update"  => {
-        next:  "finish_dialog"
+        next:  "restart_yast"
+      },
+      "restart_yast"    => {
+        next:  :next
       },
       "finish_dialog"   => {
         abort: :abort,
@@ -96,12 +104,14 @@ def run
 
     def aliases
       {
+        "start"           => ->() { start },
         "create_backup"   => ->() { create_backup },
         "create_snapshot" => ->() { create_snapshot },
         "restore"         => ->() { restore_state },
         "perform_update"  => ->() { perform_update },
         "proposals"       => ->() { proposals },
         "repositories"    => ->() { repositories },
+        "restart_yast"    => ->() { restart_yast },
         "finish_dialog"   => ->() { finish_dialog }
       }
     end
@@ -187,5 +197,14 @@ def finish_dialog
 
       ret
     end
+
+    def start
+      Restarter.instance.restarted ? :restart : :start
+    end
+
+    def restart_yast
+      Restarter.instance.restart_yast
+      :next
+    end
   end
 end

src/lib/migration/restarter.rb

@@ -0,0 +1,41 @@
+
+require "yast"
+
+require "singleton"
+
+module Migration
+  # this class handles restarting the YaST module during online migration
+  class Restarter
+    include Singleton
+
+    Yast.import "Installation"
+    Yast.import "Directory"
+
+    RESTART_FILE = Yast::Installation.restart_file
+    # the generic restart file is removed by the yast script before starting
+    # YaST again, we need an extra file to distinguish restart and full start
+    MIGRATION_RESTART = Yast::Directory.vardir + "/migration_restarted"
+
+    attr_reader :restarted
+
+    # read the restart flag and remove it immediately to avoid
+    # possible restart loop
+    def initialize
+      @restarted = File.exist?(MIGRATION_RESTART)
+
+      clear_restart
+    end
+
+    # set the restart flag
+    def restart_yast
+      File.write(RESTART_FILE, "")
+      File.write(MIGRATION_RESTART, "")
+    end
+
+    # clear the set restart flags
+    def clear_restart
+      File.unlink(RESTART_FILE) if File.exist?(RESTART_FILE)
+      File.unlink(MIGRATION_RESTART) if File.exist?(MIGRATION_RESTART)
+    end
+  end
+end

test/finish_dialog_test.rb

@@ -75,6 +75,5 @@
       expect(subject.run).to eq(:next)
       expect(subject.reboot).to eq(false)
     end
-
   end
 end

test/main_workflow_test.rb

@@ -21,6 +21,7 @@
 require_relative "test_helper"
 
 require "migration/main_workflow"
+require "migration/restarter"
 
 describe Migration::MainWorkflow do
   describe ".run" do
@@ -49,6 +50,9 @@ def mock_client(name, res)
       # simulate snapper failure (to have a better code coverage)
       allow(Yast::Report).to receive(:Error).with(/Failed to create filesystem snapshot/)
 
+      allow(File).to receive(:write).with(Migration::Restarter::MIGRATION_RESTART, "")
+      allow(File).to receive(:write).with(Migration::Restarter::RESTART_FILE, "")
+
       allow_any_instance_of(Migration::FinishDialog).to receive(:run).and_return(:next)
       allow_any_instance_of(Migration::FinishDialog).to receive(:reboot).and_return(false)
     end
@@ -75,6 +79,7 @@ def mock_client(name, res)
 
     it "reboots the system at the end when requested" do
       allow_any_instance_of(Migration::FinishDialog).to receive(:reboot).and_return(true)
+      allow_any_instance_of(Migration::Restarter).to receive(:restarted).and_return(true)
 
       expect(Yast::SCR).to receive(:Execute).with(bash_path,
         Migration::MainWorkflow::REBOOT_COMMAND).and_return(cmd_success)
@@ -84,6 +89,7 @@ def mock_client(name, res)
 
     it "reports an error when reboot fails" do
       allow_any_instance_of(Migration::FinishDialog).to receive(:reboot).and_return(true)
+      allow_any_instance_of(Migration::Restarter).to receive(:restarted).and_return(true)
 
       expect(Yast::SCR).to receive(:Execute).with(bash_path,
         Migration::MainWorkflow::REBOOT_COMMAND).and_return(cmd_fail)

test/restarter_test.rb

@@ -0,0 +1,76 @@
+# ------------------------------------------------------------------------------
+# Copyright (c) 2015 SUSE LLC, All Rights Reserved.
+#
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of version 2 of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program 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
+# this program; if not, contact SUSE LLC.
+#
+# To contact SUSE about this file by physical or electronic mail, you may find
+# current contact information at www.suse.com.
+# ------------------------------------------------------------------------------
+
+require_relative "test_helper"
+
+require "migration/restarter"
+
+describe Migration::Restarter do
+  # create a new anonymous instance for each test to avoid test dependencies
+  # see http://stackoverflow.com/a/26172556/633234
+  subject { Class.new(Migration::Restarter).instance }
+
+  describe "#restarted" do
+    before do
+      allow(File).to receive(:exist?).with(Migration::Restarter::RESTART_FILE)
+        .and_return(false)
+    end
+
+    context "restart flag set" do
+      before do
+        expect(File).to receive(:exist?).with(Migration::Restarter::MIGRATION_RESTART)
+          .twice.and_return(true)
+      end
+
+      it "removes the restart flag and returns true" do
+        expect(File).to receive(:unlink).with(Migration::Restarter::MIGRATION_RESTART)
+        expect(subject.restarted).to eq(true)
+      end
+    end
+
+    context "restart flag not set" do
+      before do
+        expect(File).to receive(:exist?).with(Migration::Restarter::MIGRATION_RESTART)
+          .twice.and_return(false)
+      end
+
+      it "returns false" do
+        expect(File).to_not receive(:unlink).with(Migration::Restarter::MIGRATION_RESTART)
+        expect(subject.restarted).to eq(false)
+      end
+    end
+  end
+
+  describe "#restart_yast" do
+    before do
+      allow(File).to receive(:exist?).with(Migration::Restarter::MIGRATION_RESTART)
+        .and_return(false)
+      allow(File).to receive(:exist?).with(Migration::Restarter::RESTART_FILE)
+        .and_return(false)
+    end
+
+    it "set the restart flags" do
+      expect(File).to receive(:write).with(Migration::Restarter::RESTART_FILE, "")
+      expect(File).to receive(:write).with(Migration::Restarter::MIGRATION_RESTART, "")
+
+      subject.restart_yast
+    end
+  end
+end