Module: Magma::Utils

Included in:
Preparer, Reifier, Renderer, Templater
Defined in:
lib/magma/utils.rb

Instance Method Summary collapse

Instance Method Details

#pipe(object, methods = []) ⇒ Object

Applies methods/procs to an object in order



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# File 'lib/magma/utils.rb', line 17

def pipe(object, methods = [])
  methods.reduce(object) do |acc, method|
    case method
    when Proc || method.respond_to?(:call)
      method.call(acc)
    when Symbol
      send(method, acc)
    when String
      raise "must start with '.'" unless method[0] == '.'
      acc.send(method[1..-1].to_sym)
    else
      raise "unexpected pipe #{method}"
    end
  end
end

#read_file_or_stdin(filename = nil) ⇒ Object

Reads a file or from STDIN if piped



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# File 'lib/magma/utils.rb', line 6

def read_file_or_stdin(filename = nil)
  filename.nil? ? !STDIN.tty? && STDIN.read : File.read(filename)
end

#run(*args, &block) ⇒ Object

Delegates to Open3



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# File 'lib/magma/utils.rb', line 34

def run(*args, &block)
  return Open3.popen3(*args, &block) if block_given?
  Open3.popen3(*args)
end

#symbolize_keys(hash) ⇒ Object

Symbolizes a hash’s keys



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# File 'lib/magma/utils.rb', line 40

def symbolize_keys(hash)
  hash.each_with_object({}) { |(k, v), memo| memo[k.to_sym] = v }
end

#uuid?(uuid) ⇒ Boolean

Returns whether a string is a UUID

Returns:

  • (Boolean) 


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# File 'lib/magma/utils.rb', line 11

def uuid?(uuid)
  uuid_regex = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/
  uuid_regex =~ uuid.to_s.downcase
end

#which(cmd) ⇒ Object

Cross-platform way of finding an executable in the $PATH Reference: stackoverflow.com/a/5471032/3557448



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# File 'lib/magma/utils.rb', line 46

def which(cmd)
  return cmd if File.exist?(cmd) && File.executable?(cmd)
  exts = ENV['PATHEXT'] ? ENV['PATHEXT'].split(';') : ['']
  ENV['PATH'].split(File::PATH_SEPARATOR).each do |path|
    exts.each do |ext|
      exe = File.join(path, "#{cmd}#{ext}")
      return exe if File.executable?(exe) && !File.directory?(exe)
    end
  end
  nil
end