Class: NagiosHerald::FormatterLoader

Inherits:
Object
  • Object
show all
Includes:
Logging
Defined in:
lib/nagios-herald/formatter_loader.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Logging

#configure_logger_for, #logger, #logger_for

Constructor Details

#initialize ⇒ FormatterLoader

Public: Initialize the formatter loader module. Adds the path to the built-in formatters to the module variable @formatter_paths. Adds the path to custom formatters if that option is passed to ‘nagios-herald` via ’-F|–formatter-dir’ on the command line or via the ‘formatter-dir’ option in the configuration file.



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# File 'lib/nagios-herald/formatter_loader.rb', line 21

def initialize
  @builtin_formatter_path = File.expand_path("formatters", File.dirname(__FILE__))
  @custom_formatter_path = Config.config['formatter_dir'] if Config.config['formatter_dir']
end

Instance Attribute Details

#builtin_formatter_path ⇒ Object

Returns the value of attribute builtin_formatter_path.



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# File 'lib/nagios-herald/formatter_loader.rb', line 13

def builtin_formatter_path
  @builtin_formatter_path
end

#custom_formatter_path ⇒ Object

Returns the value of attribute custom_formatter_path.



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# File 'lib/nagios-herald/formatter_loader.rb', line 14

def custom_formatter_path
  @custom_formatter_path
end

Instance Method Details

#enum_formatter_class_files ⇒ Object

Public: Enumerate the available formatter class files.

Returns a hash of the class files’ absolute paths whose key is the formatter file’s basename and the value is the full path to the file.



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# File 'lib/nagios-herald/formatter_loader.rb', line 31

def enum_formatter_class_files
  formatter_class_files = {}

  # Iterate over the builtin formatters first.
  builtin_formatter_class_files = Dir.glob(File.expand_path("*.rb", @builtin_formatter_path))
  builtin_formatter_class_files.each do |builtin_formatter_class_file|
    formatter_class_files[File.basename(builtin_formatter_class_file)] = builtin_formatter_class_file
  end
  # If we've been told about custom formatters, add them to the hash.
  # If there are conflicts, naively merge them, with the custom formatters getting
  # priority.
  if @custom_formatter_path
    custom_formatters = {}
    custom_formatter_class_files = Dir.glob(File.expand_path("*.rb", @custom_formatter_path))
    custom_formatter_class_files.each do |custom_formatter_class_file|
      custom_formatters[File.basename(custom_formatter_class_file)] = custom_formatter_class_file
    end
    formatter_class_files.merge!(custom_formatters)
  end
  formatter_class_files
end

#formatter_class_files ⇒ Object

Public: An array of class files’ paths.

Returns an array of class files’ paths.



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# File 'lib/nagios-herald/formatter_loader.rb', line 56

def formatter_class_files
  @formatter_class_files ||= enum_formatter_class_files
end

#load_formatters ⇒ Object

Public: Load the formatters into the namespace. A formatter can then easily be instantiated later.

Returns nothing but loads the classes into the namespace.



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# File 'lib/nagios-herald/formatter_loader.rb', line 64

def load_formatters
  if formatter_class_files.empty?
    if @custom_formatter_path
      puts "#{$0}: No formatters were found in '#{@builtin_formatter_path}'" \
      " or '#{@custom_formatter_path}' (as defined by the 'formatter_dir' option)!"
    else
      puts "#{$0}: No formatters were found in '#{@builtin_formatter_path}'!"
    end
    exit 1
  else
    formatter_class_files.each do |formatter_class, formatter_class_file|
      Kernel.load formatter_class_file
    end
  end
end