Installer configuration console

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
 
     - name: Install Dependencies
       run: rake build_dependencies:install
@@ -41,7 +41,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
 
     - name: Rubocop
       run: rake check:rubocop
@@ -53,7 +53,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
 
     - name: Install Dependencies
       run: rake build_dependencies:install
@@ -68,7 +68,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
 
     - name: Yardoc
       run: rake check:doc
@@ -82,7 +82,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
 
     - name: Perl Syntax
       run: yast-ci-ruby -o perl_syntax

src/lib/installation/console.rb

@@ -0,0 +1,87 @@
+# ------------------------------------------------------------------------------
+# Copyright (c) 2021 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.
+#
+# ------------------------------------------------------------------------------
+
+require "yast"
+require "installation/console/commands"
+require "installation/console/gui"
+require "installation/console/tui"
+
+Yast.import "UI"
+
+# Override the IRB to log all executed commands into the y2log so we know
+# what exactly happened there (in case user did something wrong or strange...)
+module IrbLogger
+  # wrap the original "evaluate" method, do some logging around
+  def evaluate(*args)
+    statements = args[1]
+    # do not log the internal IRB command for setting the last value variable
+    if statements.is_a?(::String) && statements.start_with?("_ = ")
+      super
+    else
+      Yast::Y2Logger.instance.info "Executing console command: #{statements.inspect}"
+      ret = super
+      Yast::Y2Logger.instance.info "Console command result: #{ret.inspect}"
+      ret
+    end
+  end
+end
+
+# inject the code
+require "irb/workspace"
+module IRB # :nodoc:
+  class WorkSpace
+    prepend IrbLogger
+  end
+end
+
+module Installation
+  module Console
+    class << self
+      # open a console and run an interactive IRB session in it
+      # testing in installed system:
+      # ruby -I src/lib -r installation/console.rb -e ::Installation::Console.run
+      def run
+        console = Yast::UI.TextMode ? Console::Tui.new : Console::Gui.new
+        console.run do
+          commands = Console::Commands.new(console)
+          # print the basic help text
+          commands.welcome
+
+          # start an IRB session in the context of the "commands" object
+          irb(commands)
+        end
+      end
+
+    private
+
+      # configure IRB and start an interactive session
+      # @param context [Object] context in which the IRB session runs
+      def irb(context)
+        # lazy loading
+        require "irb"
+        # enable TAB completion
+        require "irb/completion"
+
+        # see the Binding::irb method in irb.rb in the Ruby stdlib
+        IRB.setup(eval("__FILE__"), argv: [])
+        # use a simple prompt with some customizations
+        IRB.conf[:PROMPT][:YAST] = IRB.conf[:PROMPT][:SIMPLE].dup
+        IRB.conf[:PROMPT][:YAST][:RETURN] = ""
+        IRB.conf[:PROMPT][:YAST][:PROMPT_I] = "YaST >> "
+        IRB.conf[:PROMPT_MODE] = :YAST
+        workspace = IRB::WorkSpace.new(context)
+        IRB::Irb.new(workspace).run(IRB.conf)
+      end
+    end
+  end
+end

src/lib/installation/console/commands.rb

@@ -0,0 +1,96 @@
+# ------------------------------------------------------------------------------
+# Copyright (c) 2021 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.
+#
+# ------------------------------------------------------------------------------
+
+require "pp"
+require "shellwords"
+
+require "yast"
+require "installation/console/plugins"
+
+module Installation
+  module Console
+    class Commands
+      include Yast::I18n
+
+      # This class implements the commands in the installer console,
+      # the actual commands are implemented as plugins loaded from
+      # lib/installation/console/plugins/*.rb files
+      #
+      # All public methods in this class are the commands available in the console,
+      # that means we cannot include Yast::Logger here because it would define
+      # "log" command. For logging we have to use the full form here, e.g.
+      # Yast::Y2Logger.instance.info
+      def initialize(console)
+        textdomain "installation"
+
+        @console = console
+        Plugins.load_plugins
+      end
+
+      # print the "welcome" message with a basic help text
+      def welcome
+        puts "---- This is the YaST Installation Console ----"
+        puts
+        # this is the most important message so make it translatable,
+        # the console is for experts so it is OK have the rest untranslated
+        # TRANSLATORS: help text displayed in the installer command line console
+        puts _("Type 'quit' or press Ctrl+D to close the console and go back to the installer")
+        puts
+        puts "Type 'commands' to see the available special commands"
+        puts
+        puts "This is a Ruby shell, you can also type any Ruby command here"
+        puts "and inspect or change the YaST installer"
+        puts
+        puts "Hints: <Tab> completion is enabled, the command history is kept,"
+        puts "you can use the usual \"readline\" features..."
+        puts
+      end
+
+      # print the available commands
+      def commands
+        puts "Available commands:"
+        puts
+        print_command("quit", "Close the console and return back to the installer")
+
+        private_methods.grep(/_description$/).sort.each do |method|
+          print_command(method.to_s.sub(/_description$/, ""), send(method))
+        end
+
+        puts
+      end
+
+      # all unknown commands are handled via this "method_missing" callback
+      def method_missing(method_name, *_args)
+        Yast::Y2Logger.instance.info "Entered unknown command: #{method_name.inspect}"
+        puts "Error: Unknown command \"#{method_name}\""
+        puts
+        commands
+      end
+
+      # helper for running an YaST module
+      def run_yast_module(*args)
+        @console.run_yast_module(*args)
+      end
+
+    private
+
+      # print help text for a command
+      def print_command(cmd, descr)
+        # indent multiline descriptions
+        description = descr.gsub("\n", "\n    ")
+        puts "  #{cmd} - #{description}"
+        puts
+      end
+    end
+  end
+end

src/lib/installation/console/gui.rb

@@ -0,0 +1,136 @@
+# ------------------------------------------------------------------------------
+# Copyright (c) 2021 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.
+#
+# ------------------------------------------------------------------------------
+
+require "yast"
+
+module Installation
+  module Console
+    # the installer console implementation for the graphical (Qt) UI
+    class Gui
+      Yast.import "Wizard"
+
+      # open a console and run a block in it
+      def run(&block)
+        start
+        redirect(&block)
+      ensure
+        stop
+      end
+
+      # helper for running an YaST module in console
+      def run_yast_module(*args)
+        # we cannot run any YaST module if there is a popup displayed, the module
+        # would be displayed *below* the popup making it inaccessible :-(
+        # make sure a wizard dialog is at the top
+        return unless wizard_dialog?
+
+        begin
+          # get the window ID of the currently active window (the xterm window)
+          window = `#{SWITCHER}`.chomp
+        rescue Errno::ENOENT
+          # if the switcher is missing display a short help
+          puts "Starting an YaST configuration module..."
+          puts
+          puts "After it is finished (by pressing [Next]/[Back]/[Abort])"
+          puts "press Alt+Tab to get back to this console."
+
+          # wait a bit so the user can read the message above
+          sleep(5)
+        end
+
+        Yast::WFM.call(*args)
+
+        # automatically switch the window focus from YaST back to the xterm window
+        system("#{SWITCHER} #{Shellwords.escape(window)}") if window
+      end
+
+    private
+
+      # path to the window switching helper tool (from yast2-x11)
+      SWITCHER = "/usr/lib/YaST2/bin/active_window".freeze
+
+      # is the toplevel dialog a wizard dialog? We cannot run an YaST module
+      # if a popup is currently displayed...
+      def wizard_dialog?
+        return true if Yast::Wizard.IsWizardDialog
+
+        puts "Error: YaST modules cannot be started if there is a popup dialog"
+        puts "displayed. First close this console then close the popup in the installer"
+        puts "and then start the console again."
+
+        false
+      end
+
+      # start the console, open a new xterm window
+      def start
+        # create a pipe for communication with the shell running in the xterm
+        @read, @write = IO.pipe
+        # get the /proc path for the reading end of the pipe
+        read_path = fd_path(Process.pid, @read.fileno)
+
+        # start a new xterm window, run a shell command which:
+        # 1. opens a watching FD for signaling exit
+        # 2. "echo" command prints the PID, the watching FD and the terminal
+        #    device to the Ruby pipe above
+        # 3. "read" command keeps the xterm window open until any input is sent
+        #    to the watching FD
+        command = "xterm -title \"YaST Installation Console\" -e bash -c \"exec {CLOSEFD}<> <(:);
+                    echo \\$\\$ \\$CLOSEFD \\$(tty) > #{read_path};
+                    read -u \\$CLOSEFD\" &"
+
+        system(command)
+
+        # read the values printed by the "echo" command above
+        @pid, @close_fd, @tty = @read.readline.split
+      end
+
+      # stop the console, close the xterm window
+      def stop
+        # send an empty string to the waiting "read" process
+        File.write(fd_path(@pid, @close_fd), "\n") if @pid && @close_fd
+        # close the pipes
+        @read.close if @read
+        @write.close if @write
+      end
+
+      # run a block with redirected IO (redirect to the started xterm console)
+      def redirect(&block)
+        # remember the initial IO channels
+        stdout_orig = $stdout.dup
+        stderr_orig = $stderr.dup
+        stdin_orig = $stdin.dup
+
+        # redirect all IO to the xterm window (its tty device)
+        $stdout.reopen(@tty)
+        $stderr.reopen(@tty)
+        $stdin.reopen(@tty)
+
+        begin
+          block.call if block_given?
+        ensure
+          # restore the original IO channels
+          $stdout.reopen(stdout_orig)
+          $stderr.reopen(stderr_orig)
+          $stdin.reopen(stdin_orig)
+        end
+      end
+
+      # get /proc path for a file descriptor
+      # @param pid [String, Integer] PID of the process
+      # @param fd [String, Integer] file descriptor number
+      def fd_path(pid, fd)
+        "/proc/#{pid}/fd/#{fd}"
+      end
+    end
+  end
+end