Initial extraction of ShellOut from Chef

1 files changed, 237 insertions, 0 deletions

diff --git a/lib/mixlib/shellout.rb b/lib/mixlib/shellout.rb
new file mode 100644
index 0000000..88a666d
--- /dev/null
+++ b/lib/mixlib/shellout.rb
@@ -0,0 +1,237 @@
+#--
+# Author:: Daniel DeLeo (<dan@opscode.com>)
+# Copyright:: Copyright (c) 2010 Opscode, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require 'etc'
+require 'tmpdir'
+require 'chef/log'
+require 'fcntl'
+require 'mixlib/shellout/exceptions'
+
+module Mixlib
+
+  class ShellOut
+    READ_WAIT_TIME = 0.01
+    READ_SIZE = 4096
+    DEFAULT_READ_TIMEOUT = 600
+    DEFAULT_ENVIRONMENT = {'LC_ALL' => 'C'}
+
+    if RUBY_PLATFORM =~ /mswin|mingw32|windows/
+      require 'mixlib/shellout/windows'
+      include ShellOut::Windows
+    else
+      require 'mixlib/shellout/unix'
+      include ShellOut::Unix
+    end
+
+    attr_accessor :user
+    attr_accessor :group
+    attr_accessor :cwd
+    attr_accessor :valid_exit_codes
+    attr_accessor :live_stream
+    attr_accessor :command_log_level
+    attr_accessor :command_log_prepend
+
+    attr_reader :command, :umask, :environment
+    attr_writer :timeout
+    attr_reader :execution_time
+
+    attr_reader :stdout, :stderr, :status
+
+    attr_reader :stdin_pipe, :stdout_pipe, :stderr_pipe, :process_status_pipe
+
+    # === Arguments:
+    # Takes a single command, or a list of command fragments. These are used
+    # as arguments to Kernel.exec. See the Kernel.exec documentation for more
+    # explanation of how arguments are evaluated. The last argument can be an
+    # options Hash.
+    # === Options:
+    # If the last argument is a Hash, it is removed from the list of args passed
+    # to exec and used as an options hash. The following options are available:
+    # * +user+: the user the commmand should run as. if an integer is given, it is
+    #   used as a uid. A string is treated as a username and resolved to a uid
+    #   with Etc.getpwnam
+    # * +group+: the group the command should run as. works similarly to +user+
+    # * +cwd+: the directory to chdir to before running the command
+    # * +umask+: a umask to set before running the command. If given as an Integer,
+    #   be sure to use two leading zeros so it's parsed as Octal. A string will
+    #   be treated as an octal integer
+    # * +returns+:  one or more Integer values to use as valid exit codes for the
+    #   subprocess. This only has an effect if you call +error!+ after
+    #   +run_command+.
+    # * +environment+: a Hash of environment variables to set before the command
+    #   is run. By default, the environment will *always* be set to 'LC_ALL' => 'C'
+    #   to prevent issues with multibyte characters in Ruby 1.8. To avoid this,
+    #   use :environment => nil for *no* extra environment settings, or
+    #   :environment => {'LC_ALL'=>nil, ...} to set other environment settings
+    #   without changing the locale.
+    # * +timeout+: a Numeric value for the number of seconds to wait on the
+    #   child process before raising an Exception. This is calculated as the
+    #   total amount of time that ShellOut waited on the child process without
+    #   receiving any output (i.e., IO.select returned nil). Default is 60
+    #   seconds. Note: the stdlib Timeout library is not used.
+    # === Examples:
+    # Invoke find(1) to search for .rb files:
+    #   find = Chef::ShellOut.new("find . -name '*.rb'")
+    #   find.run_command
+    #   # If all went well, the results are on +stdout+
+    #   puts find.stdout
+    #   # find(1) prints diagnostic info to STDERR:
+    #   puts "error messages" + find.stderr
+    #   # Raise an exception if it didn't exit with 0
+    #   find.error!
+    # Run a command as the +www+ user with no extra ENV settings from +/tmp+
+    #   cmd = Chef::ShellOut.new("apachectl", "start", :user => 'www', :env => nil, :cwd => '/tmp')
+    #   cmd.run_command # etc.
+    def initialize(*command_args)
+      @stdout, @stderr = '', ''
+      @live_stream = nil
+      @command_log_level = :debug
+      @command_log_prepend = nil 
+      @environment = DEFAULT_ENVIRONMENT
+      @cwd = nil
+      @valid_exit_codes = [0]
+
+      if command_args.last.is_a?(Hash)
+        parse_options(command_args.pop)
+      end
+
+      @command = command_args.size == 1 ? command_args.first : command_args
+    end
+
+    def umask=(new_umask)
+      @umask = (new_umask.respond_to?(:oct) ? new_umask.oct : new_umask.to_i) & 007777
+    end
+
+    def uid
+      return nil unless user
+      user.kind_of?(Integer) ? user : Etc.getpwnam(user.to_s).uid
+    end
+
+    def gid
+      return nil unless group
+      group.kind_of?(Integer) ? group : Etc.getgrnam(group.to_s).gid
+    end
+
+    def timeout
+      @timeout || DEFAULT_READ_TIMEOUT
+    end
+
+    # Creates a String showing the output of the command, including a banner
+    # showing the exact command executed. Used by +invalid!+ to show command
+    # results when the command exited with an unexpected status.
+    def format_for_exception
+      msg = ""
+      msg << "---- Begin output of #{command} ----\n"
+      msg << "STDOUT: #{stdout.strip}\n"
+      msg << "STDERR: #{stderr.strip}\n"
+      msg << "---- End output of #{command} ----\n"
+      msg << "Ran #{command} returned #{status.exitstatus}" if status
+      msg
+    end
+
+    def exitstatus
+      @status && @status.exitstatus
+    end
+
+    # Run the command, writing the command's standard out and standard error
+    # to +stdout+ and +stderr+, and saving its exit status object to +status+
+    # === Returns
+    # returns   +self+; +stdout+, +stderr+, +status+, and +exitstatus+ will be
+    # populated with results of the command
+    # === Raises
+    # * Errno::EACCES  when you are not privileged to execute the command
+    # * Errno::ENOENT  when the command is not available on the system (or not
+    #   in the current $PATH)
+    # * ::CommandTimeout  when the command does not complete
+    #   within +timeout+ seconds (default: 60s)
+    def run_command
+      if command_log_prepend
+        Chef::Log.send(command_log_level, "#{command_log_prepend} sh(#{@command})")
+      else
+        Chef::Log.send(command_log_level, "sh(#{@command})")
+      end
+      super
+    end
+
+    # Checks the +exitstatus+ against the set of +valid_exit_codes+. If
+    # +exitstatus+ is not in the list of +valid_exit_codes+, calls +invalid!+,
+    # which raises an Exception.
+    # === Returns
+    # nil::: always returns nil when it does not raise
+    # === Raises
+    # ::ShellCommandFailed::: via +invalid!+
+    def error!
+      unless Array(valid_exit_codes).include?(exitstatus)
+        invalid!("Expected process to exit with #{valid_exit_codes.inspect}, but received '#{exitstatus}'")
+      end
+    end
+
+    # Raises a ::ShellCommandFailed exception, appending the
+    # command's stdout, stderr, and exitstatus to the exception message.
+    # === Arguments
+    # +msg+:  A String to use as the basis of the exception message. The
+    # default explanation is very generic, providing a more informative message
+    # is highly encouraged.
+    # === Raises
+    # ::ShellCommandFailed  always
+    def invalid!(msg=nil)
+      msg ||= "Command produced unexpected results"
+      raise ShellCommandFailed, msg + "\n" + format_for_exception
+    end
+
+    def inspect
+      "<#{self.class.name}##{object_id}: command: '#@command' process_status: #{@status.inspect} " +
+      "stdout: '#{stdout.strip}' stderr: '#{stderr.strip}' child_pid: #{@child_pid.inspect} " +
+      "environment: #{@environment.inspect} timeout: #{timeout} user: #@user group: #@group working_dir: #@cwd >"
+    end
+
+    private
+
+    def parse_options(opts)
+      opts.each do |option, setting|
+        case option.to_s
+        when 'cwd'
+          self.cwd = setting
+        when 'user'
+          self.user = setting
+        when 'group'
+          self.group = setting
+        when 'umask'
+          self.umask = setting
+        when 'timeout'
+          self.timeout = setting
+        when 'returns'
+          self.valid_exit_codes = Array(setting)
+        when 'live_stream'
+          self.live_stream = setting
+        when 'command_log_level'
+          self.command_log_level = setting
+        when 'command_log_prepend'
+          self.command_log_prepend = setting
+        when 'environment', 'env'
+          # passing :environment => nil means don't set any new ENV vars
+          @environment = setting.nil? ? {} : @environment.dup.merge!(setting)
+        else
+          raise InvalidCommandOption, "option '#{option.inspect}' is not a valid option for #{self.class.name}"
+        end
+      end
+    end
+
+
+  end
+end