Class: PVN::CachableCommand

Inherits:
Command
  • Object
show all
Defined in:
lib/system/cachecmd.rb

Constant Summary collapse

TMP_DIR = 
ENV['PVN_TMP_DIR'] || '/tmp/pvncache'
CACHE_DIR = 
Pathname.new TMP_DIR

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(args = Hash.new) ⇒ CachableCommand

Returns a new instance of CachableCommand.



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# File 'lib/system/cachecmd.rb', line 13

def initialize args = Hash.new
  debug "args: #{args.inspect}"

  @use_cache = args[:use_cache].nil? ? true : args[:use_cache]
  info "@use_cache: #{@use_cache}".blue

  super
end

Instance Attribute Details

#lines ⇒ Object

Returns the value of attribute lines.



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# File 'lib/system/cachecmd.rb', line 11

def lines
  @lines
end

Instance Method Details

#get_cache_file(cmd) ⇒ Object 



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# File 'lib/system/cachecmd.rb', line 44

def get_cache_file cmd
  pwd = Pathname.pwd.to_s.sub(%r{^/}, '')
  CACHE_DIR + pwd + cmd.gsub(' ', '')
end

#run(args) ⇒ Object 



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# File 'lib/system/cachecmd.rb', line 32

def run args
  if use_cache?
    run_cached_command args
  else
    super
  end      
end

#run_cached_command(cmd) ⇒ Object 



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# File 'lib/system/cachecmd.rb', line 49

def run_cached_command cmd
  stack "cmd: #{cmd}".cyan
  cfile = get_cache_file cmd
  if cfile.exist?
    debug "reading from cache file: #{cfile}".cyan
    @output = cfile.readlines
  else
    @output = ::IO::popen(cmd).readlines
    cfile.parent.mkpath
    stack "saving output to cache file: #{cfile}".cyan
    File.put_via_temp_file cfile do
      output
    end
  end
end

#sysexec(cmd) ⇒ Object 



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# File 'lib/system/cachecmd.rb', line 22

def sysexec cmd
  info "cmd: #{cmd}".on_red
  if use_cache?
    info "cmd: #{cmd}".on_green
    run_cached_command cmd
  else
    @output = ::IO::popen(cmd).readlines
  end
end

#use_cache? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/system/cachecmd.rb', line 40

def use_cache?
  @use_cache
end