Class: Measured::Cache::Json

Inherits:
Object
  • Object
show all
Defined in:
lib/measured/cache/json.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(filename) ⇒ Json

Returns a new instance of Json.

Raises:

  • (ArgumentError) 


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# File 'lib/measured/cache/json.rb', line 6

def initialize(filename)
  @filename = filename
  raise ArgumentError, "Invalid cache file: #{filename}" unless %w[length.json weight.json volume.json test.json].include?(filename.to_s)
  @path = Pathname.new(File.join(File.dirname(__FILE__), "../../../cache", filename)).cleanpath
end

Instance Attribute Details

#filename ⇒ Object (readonly)

Returns the value of attribute filename.



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# File 'lib/measured/cache/json.rb', line 4

def filename
  @filename
end

#path ⇒ Object (readonly)

Returns the value of attribute path.



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# File 'lib/measured/cache/json.rb', line 4

def path
  @path
end

Instance Method Details

#exist? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/measured/cache/json.rb', line 12

def exist?
  File.exist?(@path)
end

#read ⇒ Object 



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# File 'lib/measured/cache/json.rb', line 16

def read
  return unless exist?
  decode(JSON.load(File.read(@path), nil, freeze: true))
end

#write(table) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/measured/cache/json.rb', line 21

def write(table)
  raise ArgumentError, "Cannot overwrite file cache at runtime."
end