123456789_123456789_123456789_123456789_123456789_

Class: ActiveStorage::Analyzer

Relationships & Source Files
Namespace Children
Classes:
AudioAnalyzer, ImageAnalyzer, NullAnalyzer, VideoAnalyzer
Extension / Inclusion / Inheritance Descendants
Subclasses:
AudioAnalyzer, ImageAnalyzer, NullAnalyzer, VideoAnalyzer, ImageAnalyzer::ImageMagick, ImageAnalyzer::Vips
Inherits: Object
Defined in: activestorage/lib/active_storage/analyzer.rb

Overview

This is an abstract base class for analyzers, which extract metadata from blobs. See VideoAnalyzer for an example of a concrete subclass.

Class Attribute Summary

Class Method Summary

Instance Attribute Summary

Instance Method Summary

Constructor Details

.new(blob) ⇒ Analyzer

[ GitHub ] 

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 23



def initialize(blob)
  @blob = blob
end


  







Class Attribute Details



  

    .analyze_later?  ⇒ Boolean  (readonly)
  



  

    

Implement this method in concrete subclasses. It will determine if blob analysis should be done in a job or performed inline. By default, analysis is enqueued in a job.


  





  


  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 19



def self.analyze_later?
  true
end


  







Class Method Details



  

    .accept?(blob)  ⇒ Boolean 
  



  

    

Implement this method in a concrete subclass. Have it return true when given a blob from which the analyzer can extract metadata.


  





  


  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 13



def self.accept?(blob)
  false
end


  







Instance Attribute Details



  

    #blob   (readonly)
  

  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 9



attr_reader :blob


  







Instance Method Details



  

    #download_blob_to_tempfile(&block)   (private)
  



  

    

Downloads the blob to a tempfile on disk. Yields the tempfile.


  



  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 34



def download_blob_to_tempfile(&block) # :doc:
  blob.open tmpdir: tmpdir, &block
end


  








  

    #instrument(analyzer, &block)   (private)
  

  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 46



def instrument(analyzer, &block) # :doc:
  ActiveSupport::Notifications.instrument("analyze.active_storage", analyzer: analyzer, &block)
end


  








  

    #logger   (private)
  

  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 38



def logger # :doc:
  ActiveStorage.logger
end


  








  

    #metadata  
  



  

    

Override this method in a concrete subclass. Have it return a ::Hash of metadata.


  





  
Raises:


    
  
  • 
    (NotImplementedError)
  
    • 





  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 28



def metadata
  raise NotImplementedError
end


  








  

    #tmpdir   (private)
  

  [ GitHub ]


  

  


# File 'activestorage/lib/active_storage/analyzer.rb', line 42



def tmpdir # :doc:
  Dir.tmpdir
end