Class: Aspera::Environment

Inherits:
Object
  • Object
show all
Includes:
Singleton
Defined in:
lib/aspera/environment.rb

Overview

detect OS, architecture, and specific stuff

Constant Summary collapse

OS_WINDOWS = 
:windows
OS_MACOS = 
:osx
OS_LINUX = 
:linux
OS_AIX = 
:aix
OS_LIST = 
[OS_WINDOWS, OS_MACOS, OS_LINUX, OS_AIX].freeze
CPU_X86_64 = 
:x86_64
CPU_ARM64 = 
:arm64
CPU_PPC64 = 
:ppc64
CPU_PPC64LE = 
:ppc64le
CPU_S390 = 
:s390
CPU_LIST = 
[CPU_X86_64, CPU_ARM64, CPU_PPC64, CPU_PPC64LE, CPU_S390].freeze
BITS_PER_BYTE = 
8
MEBI = 
1024 * 1024
BYTES_PER_MEBIBIT = 
MEBI / BITS_PER_BYTE
I18N_VARS = 
%w(LC_ALL LC_CTYPE LANG).freeze
WINDOWS_FILENAME_INVALID_CHARACTERS =

“/” is invalid on both Unix and Windows, other are Windows special characters See: learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file

'<>:"/\\|?*'
REPLACE_CHARACTER = 
'_'
RB_EXT = 
'.rb'
PROCESS_MODES = 
%i[execute background capture].freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Environment

Returns a new instance of Environment.



204
205
206
 
# File 'lib/aspera/environment.rb', line 204

def initialize
  initialize_fields
end

Instance Attribute Details

#cpu ⇒ Object (readonly)

Returns the value of attribute cpu.



202
203
204
 
# File 'lib/aspera/environment.rb', line 202

def cpu
  @cpu
end

#default_gui_mode ⇒ Object (readonly)

Returns the value of attribute default_gui_mode.



202
203
204
 
# File 'lib/aspera/environment.rb', line 202

def default_gui_mode
  @default_gui_mode
end

#file_illegal_characters ⇒ Object

Returns the value of attribute file_illegal_characters.



201
202
203
 
# File 'lib/aspera/environment.rb', line 201

def file_illegal_characters
  @file_illegal_characters
end

#os ⇒ Object (readonly)

Returns the value of attribute os.



202
203
204
 
# File 'lib/aspera/environment.rb', line 202

def os
  @os
end

#url_method ⇒ Object

Returns the value of attribute url_method.



201
202
203
 
# File 'lib/aspera/environment.rb', line 201

def url_method
  @url_method
end

Class Method Details

.build_spawn_argv(cmd, kwargs) ⇒ Object

Build argv for Process.spawn / Kernel.system (no shell)

Parameters:

  • cmd (Array) —

    Command and arguments

  • kwargs (Hash) —

    Additional arguments to ‘secure_execute`



68
69
70
71
72
73
74
75
 
# File 'lib/aspera/environment.rb', line 68

def build_spawn_argv(cmd, kwargs)
  env = kwargs.delete(:env)
  argv = []
  argv << env if env
  argv << [cmd.first, cmd.first] # no shell, preserve argv[0]
  argv.concat(cmd.drop(1))
  argv
end

.empty_binding ⇒ Object

Empty variable binding for secure eval



53
54
55
 
# File 'lib/aspera/environment.rb', line 53

def empty_binding
  return Kernel.binding
end

.force_terminal_c ⇒ Object

force locale to C so that unicode characters are not used



190
191
192
 
# File 'lib/aspera/environment.rb', line 190

def force_terminal_c
  I18N_VARS.each{ |var| ENV[var] = 'C'}
end

.restrict_file_access(path, mode: nil) ⇒ Object

restrict access to a file or folder to user only



168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
 
# File 'lib/aspera/environment.rb', line 168

def restrict_file_access(path, mode: nil)
  if mode.nil?
    # or FileUtils ?
    if File.file?(path)
      mode = 0o600
    elsif File.directory?(path)
      mode = 0o700
    else
      Log.log.debug{"No restriction can be set for #{path}"}
    end
  end
  File.chmod(mode, path) unless mode.nil?
rescue => e
  Log.log.warn(e.message)
end

.ruby_version ⇒ Object 



48
49
50
 
# File 'lib/aspera/environment.rb', line 48

def ruby_version
  return RbConfig::CONFIG['RUBY_PROGRAM_VERSION']
end

.secure_eval(code, file, line, user_binding = nil) ⇒ Object

Secure execution of Ruby code

Parameters:

  • code (String) —

    Ruby code to execute

  • file (String) —

    File name for error reporting

  • line (Integer) —

    Line number for error reporting



61
62
63
 
# File 'lib/aspera/environment.rb', line 61

def secure_eval(code, file, line, user_binding = nil)
  Kernel.send('lave'.reverse, code, user_binding || empty_binding, file, line)
end

.secure_execute(*cmd, mode: :execute, **kwargs) ⇒ Boolean, ...

Executes a command without invoking a shell.

The command is provided as an array to avoid shell interpolation and ensure safer execution.

Parameters:

  • cmd (Array<#to_s>) —

    The executable and its arguments.

  • mode (:execute, :background, :capture) (defaults to: :execute) —

    The execution strategy:

    • ‘:execute` Uses Kernel.system. Returns `true`, `false`, or `nil`. (Default)

    • ‘:background` Uses Process.spawn. Returns the spawned process PID.

    • ‘:capture` Uses Open3.capture3. Returns captured out, err, and status.

  • kwargs (Hash) —

    Additional options forwarded to the underlying call.

Options Hash (**kwargs):

  • :env (Hash{String => String}) —

    Environment variables to set for the process.

  • :exception (Boolean) — default: false —

    When ‘true` in `:capture` mode, raises an error if the command exits with a non-zero status.

  • :close_others (Boolean) — default: true —

    When ‘true` in `:background` mode, closes all other file descriptors in the child process.

Returns:

  • (Boolean, nil) —

    For ‘:execute` mode (`true`, `false`, or `nil`).

  • (Integer) —

    For ‘:background` mode (process ID).

  • (Array(String, String, Process::Status)) —

    For ‘:capture` mode (`stdout`, `stderr`, `status`).

Raises:

  • (RuntimeError) —

    If ‘:exception` is `true` and the process fails in `:capture` mode.



112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
 
# File 'lib/aspera/environment.rb', line 112

def secure_execute(*cmd, mode: :execute, **kwargs)
  cmd = cmd.map(&:to_s)
  Aspera.assert(cmd.size.positive?, type: ArgumentError){'executable must be present'}
  Aspera.assert_values(mode, PROCESS_MODES, type: ArgumentError){'mode'}
  Log.log.debug do
    parts = [mode.to_s, 'command:']
    kwargs[:env]&.each{ |k, v| parts << "#{k}=#{shell_escape_pretty(v.to_s)}"}
    cmd.each{ |a| parts << shell_escape_pretty(a)}
    parts.join(' ')
  end
  case mode
  when :execute
    # https://docs.ruby-lang.org/en/master/Kernel.html#method-i-system
    # https://docs.ruby-lang.org/en/master/Process.html#module-Process-label-Execution+Options
    kwargs[:exception] = true unless kwargs.key?(:exception)
    Kernel.system(*build_spawn_argv(cmd, kwargs), **kwargs)
  when :background
    # https://docs.ruby-lang.org/en/master/Process.html#method-c-spawn
    # https://docs.ruby-lang.org/en/master/Process.html#module-Process-label-Execution+Options
    kwargs[:close_others] = true unless kwargs.key?(:close_others)
    pid = Process.spawn(*build_spawn_argv(cmd, kwargs), **kwargs)
    Log.dump(:pid, pid)
    pid
  when :capture
    # https://docs.ruby-lang.org/en/master/Open3.html#method-c-capture3
    # https://docs.ruby-lang.org/en/master/Process.html#module-Process-label-Execution+Options
    argv = [kwargs.delete(:env)].compact + cmd
    exception = kwargs.delete(:exception){true}
    result = Open3.capture3(*argv, **kwargs)
    Log.dump(:stdout, result[0], level: :trace1)
    Log.dump(:stderr, result[1], level: :trace1)
    Log.dump(:status, result[2])
    raise "Process failed: #{result[2].exitstatus} (#{result[1]})" if exception && !result[2].success?
    result
  else Aspera.error_unreachable_line
  end
end

.shell_escape_pretty(str) ⇒ Object

like ‘Shellwords.shellescape`, but does not escape `=`



78
79
80
81
82
83
84
85
 
# File 'lib/aspera/environment.rb', line 78

def shell_escape_pretty(str)
  # Safe unquoted characters + '=' explicitly allowed
  return str if str.match?(%r{\A[A-Za-z0-9_.,:/@+=-]+\z})
  # return str if Shellwords.shellescape(str) == str

  # Otherwise use single quotes
  "'#{str.gsub("'", %q('\'\''))}'"
end

.terminal? ⇒ Boolean

Returns true if we are in a terminal.

Returns:

  • (Boolean) —

    true if we are in a terminal



185
186
187
 
# File 'lib/aspera/environment.rb', line 185

def terminal?
  $stdout.tty?
end

.terminal_supports_unicode? ⇒ Boolean

www.gnu.org/software/libc/manual/html_node/Locale-Categories.html pubs.opengroup.org/onlinepubs/7908799/xbd/envvar.html

Returns:

  • (Boolean) —

    true if we can display Unicode characters



197
198
199
 
# File 'lib/aspera/environment.rb', line 197

def terminal_supports_unicode?
  terminal? && I18N_VARS.any?{ |var| ENV[var]&.include?('UTF-8')}
end

.write_file_restricted(path, force: false, mode: nil) ⇒ Object

Write content to a file, with restricted access

Parameters:

  • path (String) —

    the file path

  • force (Boolean) (defaults to: false) —

    if true, overwrite the file

  • mode (Integer) (defaults to: nil) —

    the file mode (permissions)



155
156
157
158
159
160
161
162
163
164
165
 
# File 'lib/aspera/environment.rb', line 155

def write_file_restricted(path, force: false, mode: nil)
  Aspera.assert(block_given?, type: Aspera::InternalError)
  if force || !File.exist?(path)
    # Windows may give error
    File.unlink(path) rescue nil
    # content provided by block
    File.write(path, yield)
    restrict_file_access(path, mode: mode)
  end
  return path
end

Instance Method Details

#architecture ⇒ Object

Normalized architecture name See constants: OS_* and CPU_*



251
252
253
 
# File 'lib/aspera/environment.rb', line 251

def architecture
  "#{@os}-#{@cpu}"
end

#exe_file(name = nil) ⇒ String

Add executable file extension (e.g. “.exe”) for current OS

Parameters:

  • name (String, nil) (defaults to: nil) —

    Path or file name

Returns:

  • (String) —

    Executable name with extension



258
259
260
261
 
# File 'lib/aspera/environment.rb', line 258

def exe_file(name = nil)
  return name unless @executable_extension
  return "#{name}#{@executable_extension}"
end

#fix_home ⇒ Object

on Windows, the env var %USERPROFILE% provides the path to user’s home more reliably than %HOMEDRIVE%%HOMEPATH% so, tell Ruby the right way



265
266
267
268
269
 
# File 'lib/aspera/environment.rb', line 265

def fix_home
  return unless @os.eql?(OS_WINDOWS) && ENV.key?('USERPROFILE') && Dir.exist?(ENV.fetch('USERPROFILE', nil))
  ENV['HOME'] = ENV.fetch('USERPROFILE', nil)
  Log.log.debug{"Windows: set HOME to USERPROFILE: #{Dir.home}"}
end

#graphical? ⇒ Boolean

Returns:

  • (Boolean) 


271
272
273
 
# File 'lib/aspera/environment.rb', line 271

def graphical?
  @default_gui_mode == :graphical
end

#initialize_fields ⇒ Object

initialize fields from environment



209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
 
# File 'lib/aspera/environment.rb', line 209

def initialize_fields
  @os =
    case RbConfig::CONFIG['host_os']
    when /mswin/, /msys/, /mingw/, /cygwin/, /bccwin/, /wince/, /emc/
      OS_WINDOWS
    when /darwin/, /mac os/
      OS_MACOS
    when /linux/
      OS_LINUX
    when /aix/
      OS_AIX
    else Aspera.error_unexpected_value(RbConfig::CONFIG['host_os']){'host_os'}
    end
  @cpu =
    case RbConfig::CONFIG['host_cpu']
    when /x86_64/, /x64/
      CPU_X86_64
    when /powerpc/, /ppc64/
      @os.eql?(OS_LINUX) ? CPU_PPC64LE : CPU_PPC64
    when /s390/
      CPU_S390
    when /arm/, /aarch64/
      CPU_ARM64
    else Aspera.error_unexpected_value(RbConfig::CONFIG['host_cpu']){'host_cpu'}
    end
  @executable_extension = @os.eql?(OS_WINDOWS) ? '.exe' : nil
  # :text or :graphical depending on the environment
  @default_gui_mode =
    if [Environment::OS_WINDOWS, Environment::OS_MACOS].include?(os) ||
        (ENV.key?('DISPLAY') && !ENV['DISPLAY'].empty?)
      # assume not remotely connected on macos and windows or unix family
      :graphical
    else
      :text
    end
  @url_method = @default_gui_mode
  @file_illegal_characters = REPLACE_CHARACTER + WINDOWS_FILENAME_INVALID_CHARACTERS
  nil
end

#open_editor(file_path) ⇒ Object

open a file in an editor



288
289
290
291
292
293
294
295
296
 
# File 'lib/aspera/environment.rb', line 288

def open_editor(file_path)
  if ENV.key?('EDITOR')
    self.class.secure_execute(ENV['EDITOR'], file_path.to_s)
  elsif @os.eql?(Environment::OS_WINDOWS)
    self.class.secure_execute('notepad.exe', %Q{"#{file_path}"})
  else
    open_uri_graphical(file_path.to_s)
  end
end

#open_uri(the_url) ⇒ Object

Allows a user to open a URL if method is :text, then URL is displayed on terminal if method is :graphical, then the URL will be opened with the default browser. this is non blocking



302
303
304
305
306
307
308
309
310
311
312
313
314
315
 
# File 'lib/aspera/environment.rb', line 302

def open_uri(the_url)
  case @url_method
  when :graphical
    open_uri_graphical(the_url)
  when :text
    case the_url.to_s
    when /^http/
      puts "USER ACTION: please enter this URL in a browser:\n#{the_url.to_s.red}\n"
    else
      puts "USER ACTION: open this:\n#{the_url.to_s.red}\n"
    end
  else Aspera.error_unexpected_value(@url_method){'URL open method'}
  end
end

#open_uri_graphical(uri) ⇒ Object

Open a URI in a graphical browser Command must be non blocking

Parameters:

  • uri (String) —

    the URI to open



278
279
280
281
282
283
284
285
 
# File 'lib/aspera/environment.rb', line 278

def open_uri_graphical(uri)
  case @os
  when Environment::OS_MACOS then return self.class.secure_execute('open', uri.to_s)
  when Environment::OS_WINDOWS then return self.class.secure_execute('start', 'explorer', %Q{"#{uri}"})
  when Environment::OS_LINUX   then return self.class.secure_execute('xdg-open', uri.to_s)
  else Assert.error_unexpected_value(os){'no graphical open method'}
  end
end

#safe_filename_character ⇒ String

Replacement character for illegal filename characters Can also be used as safe “join” character

Returns:



320
321
322
323
 
# File 'lib/aspera/environment.rb', line 320

def safe_filename_character
  return REPLACE_CHARACTER if @file_illegal_characters.nil? || @file_illegal_characters.empty?
  @file_illegal_characters[0]
end

#sanitized_filename(filename) ⇒ String

Sanitize a filename by replacing illegal characters

Parameters:

  • filename (String) —

    the original filename

Returns:

  • (String) —

    A file name safe to use on file system



328
329
330
331
332
333
334
335
336
337
338
339
340
341
 
# File 'lib/aspera/environment.rb', line 328

def sanitized_filename(filename)
  safe_char = safe_filename_character
  # Windows does not allow file name:
  # - with control characters anywhere
  # - ending with space or dot
  filename = filename.gsub(/[\x00-\x1F\x7F]/, safe_char)
  filename = filename.chop while filename.end_with?(' ', '.')
  if @file_illegal_characters&.size.to_i >= 2
    # replace all illegal characters with safe_char
    filename = filename.tr(@file_illegal_characters[1..-1], safe_char)
  end
  # ensure only one safe_char is used at a time
  return filename.gsub(/#{Regexp.escape(safe_char)}+/, safe_char).chomp(safe_char)
end