class PrintyPrintyBangBang

Introduction¶ ↑

PrintyPrintyBangBang is a funny little class designed to do two things:

PrintyPrinty

Print things via logPrinter
BangBang

Trigger abnormal process exits via logPrinter

Use¶ ↑

A typical mrSCPI application will not directly use PrintyPrintyBangBang instead depending on a SCPIsession instance to manage the global PrintyPrintyBangBang instance. For example, while PrintyPrintyBangBang maintains a list of global options and a PrintyPrintyBangBang#set method, most mrSCPI applications will use the SCPIsession#set in the SCPIsession class – which will forward the appropriate options to the global PrintyPrintyBangBang instance. That said, it is perfectly acceptable to use PrintyPrintyBangBang directly – if you wish to log something outside of the SCPIsession for example.

PrintyPrintyBangBang is a Singleton. The normal way to use it is as follows

PrintyPrintyBangBang.instance.logPrinter(1, "ERROR: :url was malformed: #{urlString.inspect}", self, 70)

Note that when PrintyPrintyBangBang is made aware of a new output file, it will open that file and keep it open until close is called or another file is specified. Output files are specified by strings – not file handles!

Public Class Methods

new ()

Source

# File src/mrSCPI.rb, line 1392
def initialize ()
  @gblOpt    = { :log_file       => 'STDERR',
                 :out_file       => 'STDOUT',
                 :verbose        => 1,
                 :exit_0         => false,
                 :exit_on_error  => false,
                 :print_max_len  => 0,
                 :print_debug    => false
               }
  @openFiles = { 'STDERR'    => STDERR,
                 'STDOUT'    => STDOUT,
                 '/dev/null' => nil
               }
end

Public Instance Methods

close ()

Source

# File src/mrSCPI.rb, line 1518
def close
  @openFiles.each do |fileName, fileDescriptor|
    if fileDescriptor
      fileDescriptor.close
    end
  end
end

Close all open files except STDERR, STDOUT, & /dev/null. Sets @gblOpt[:log_file] to 'STDERR' & @gblOpt[:out_file] to 'STDOUT'.

logPrinter (level, msg, source, exitCode=nil)

Source

# File src/mrSCPI.rb, line 1461
def logPrinter (level, msg, source, exitCode=nil)
  #lineNumberThatCalledUs = caller.first.to_s.sub(/^.*:([0-9]+):in.*$/, '\1')
  begin
    if @gblOpt[:verbose] >= level then
      if @openFiles[@gblOpt[:log_file]] then
        @openFiles[@gblOpt[:log_file]].puts("#{((source && source.class.to_s.upcase) || 'UNKNOWN')}: #{msg}")
        @openFiles[@gblOpt[:log_file]].flush
        #@openFiles[@gblOpt[:log_file]].fsync
      end
    end
  rescue
      if @openFiles[@gblOpt[:log_file]] != 'STDERR' then
        @openFiles[@gblOpt[:log_file]] = 'STDERR'
        retry
      else
        # Not really sure what to do here...  We couln't print to the error log file or to STDERR...
      end
  end
  if exitCode && @gblOpt[:exit_on_error] then
    if @gblOpt[:exit_0] then
      exit 0
    else
      exit exitCode
    end
  end
end

Print a message to @gblOpt[:log_file]

level

An integer. If @gblOpt[:verbose]>=level, then the message will be printed
msg

The message to print (usually a string)
source

The source of the message. It is prepended to all printed messages. Usually set to self.
exitCode

If non-nil and @gblOpt[:exit_on_error] is non-nil, then causes a process exit with the given code

outPrinter (msg, newline=true)

Source

# File src/mrSCPI.rb, line 1491
def outPrinter (msg, newline=true)
  if @openFiles[@gblOpt[:out_file]] then
    msgToPrint = msg
    truncMsg   = ''
    if @gblOpt[:print_debug] then
      msgToPrint = msgToPrint.inspect
    end
    if @gblOpt[:print_max_len] && (@gblOpt[:print_max_len] > 0) && (msg.length > @gblOpt[:print_max_len]) then
      msgToPrint = msgToPrint.slice(0, @gblOpt[:print_max_len]);
      truncMsg = "LAST LINE TRUNCATED (:print_max_len=#{@gblOpt[:print_max_len]})"
    end
    if newline || @gblOpt[:print_debug] then
      @openFiles[@gblOpt[:out_file]].puts(msgToPrint)
    else
      @openFiles[@gblOpt[:out_file]].write(msgToPrint)
    end
    if !(truncMsg.empty?) then
      @openFiles[@gblOpt[:out_file]].puts(truncMsg)
    end
    @openFiles[@gblOpt[:out_file]].flush
    #@openFiles[@gblOpt[:out_file]].fsync
  end
end

Print a message to @gblOpt[:out_file]

newline

If non-nil, then puts will be used. Otherwise write is used.

set (options)

Source

# File src/mrSCPI.rb, line 1429
def set(options)
  optionsWacked = Array.new
  [ :log_file, :out_file].each do |k|
    if options.member?(k) then
      if !(@openFiles.member?(options[k])) then
        begin
          @openFiles[options[k]] = open(options[k], "wb")
        rescue
          @openFiles.delete(options[k])
          # Note: The previous :log_file will still be set at this point, so hopefully we can print this error
          PrintyPrintyBangBang.instance.logPrinter(1, "ERROR: Failed to open file: #{options[k].inspect} for #{k.inspect}!", self, 84)
        end
      end
      optionsWacked.push(k)
    end
  end
  options.each do |opt, val|
    if @gblOpt.member?(opt) then
      @gblOpt[opt] = val
      optionsWacked.push(opt)
      options.delete(opt)
    end
  end
  return optionsWacked
end

Set options in @gblOpt. Possible options:

:log_file
:out_file
:verbose
:exit_0
:exit_on_error
:print_max_len
:print_debug

See the SCPIsession class for details on these options.

In normal mrSCPI operation, one sets these options on a SCPIsession#set, and the SCPIsession object will propagate the options through to the global PrintyPrintyBangBang instance. That said, in Ruby programs using SCPIsession, one can directly call PrintyPrintyBangBang#set if desired.

validOptions ()

Source

# File src/mrSCPI.rb, line 1411
def validOptions()
  return @gblOpt.keys
end

Return an array of valid option keys.

This is used by SCPIsession to forward options to the global PrintyPrintyBangBang instance.