class ActiveStorage::Analyzer

Active Storage Analyzer ↑

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

Attributes

Public Class Methods

accept? (blob)

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

# File activestorage/lib/active_storage/analyzer.rb, line 13
def self.accept?(blob)
  false
end
analyze_later? ()

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.

# File activestorage/lib/active_storage/analyzer.rb, line 19
def self.analyze_later?
  true
end
new (blob) 
# File activestorage/lib/active_storage/analyzer.rb, line 23
def initialize(blob)
  @blob = blob
end

Public Instance Methods

metadata ()

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

# File activestorage/lib/active_storage/analyzer.rb, line 28
def metadata
  raise NotImplementedError
end

Private Instance Methods

download_blob_to_tempfile (&block)

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

# 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) 
# 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 () 
# File activestorage/lib/active_storage/analyzer.rb, line 38
def logger # :doc:
  ActiveStorage.logger
end
tmpdir () 
# File activestorage/lib/active_storage/analyzer.rb, line 42
def tmpdir # :doc:
  Dir.tmpdir
end