Class: ActiveStorage::Service::MirrorService

Inherits:
ActiveStorage::Service show all
Defined in:
activestorage/lib/active_storage/service/mirror_service.rb

Overview

Active Storage Mirror Service

Wraps a set of mirror services and provides a single ActiveStorage::Service object that will all have the files uploaded to them. A primary service is designated to answer calls to:

  • download

  • exists?

  • url

  • url_for_direct_upload

  • headers_for_direct_upload

Instance Attribute Summary collapse

Attributes inherited from ActiveStorage::Service

#name

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from ActiveStorage::Service

#compose, configure, #download, #download_chunk, #exist?, #headers_for_direct_upload, #open, #public?, #update_metadata, #url, #url_for_direct_upload

Methods included from ActiveSupport::Autoload

#autoload, #autoload_at, #autoload_under, #eager_autoload, #eager_load!

Constructor Details

#initialize(primary:, mirrors:) ⇒ MirrorService

Returns a new instance of MirrorService.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 31

def initialize(primary:, mirrors:)
  @primary, @mirrors = primary, mirrors
  @executor = Concurrent::ThreadPoolExecutor.new(
    min_threads: 1,
    max_threads: mirrors.size,
    max_queue: 0,
    fallback_policy: :caller_runs,
    idle_time: 60
  )
end

Instance Attribute Details

#mirrors ⇒ Object (readonly)

Returns the value of attribute mirrors.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 16

def mirrors
  @mirrors
end

#primary ⇒ Object (readonly)

Returns the value of attribute primary.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 16

def primary
  @primary
end

Class Method Details

.build(primary:, mirrors:, name:, configurator:, **options) ⇒ Object

Stitch together from named services.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 22

def self.build(primary:, mirrors:, name:, configurator:, **options) # :nodoc:
  new(
    primary: configurator.build(primary),
    mirrors: mirrors.collect { |mirror_name| configurator.build mirror_name }
  ).tap do |service_instance|
    service_instance.name = name
  end
end

Instance Method Details

#delete(key) ⇒ Object

Delete the file at the key on all services.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 52

def delete(key)
  perform_across_services :delete, key
end

#delete_prefixed(prefix) ⇒ Object

Delete files at keys starting with the prefix on all services.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 57

def delete_prefixed(prefix)
  perform_across_services :delete_prefixed, prefix
end

#mirror(key, checksum:) ⇒ Object

Copy the file at the key from the primary service to each of the mirrors where it doesn’t already exist.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 66

def mirror(key, checksum:)
  instrument :mirror, key: key, checksum: checksum do
    if (mirrors_in_need_of_mirroring = mirrors.select { |service| !service.exist?(key) }).any?
      primary.open(key, checksum: checksum) do |io|
        mirrors_in_need_of_mirroring.each do |service|
          io.rewind
          service.upload key, io, checksum: checksum
        end
      end
    end
  end
end

#mirror_later(key, checksum:) ⇒ Object

:nodoc:



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 61

def mirror_later(key, checksum:) # :nodoc:
  ActiveStorage::MirrorJob.perform_later key, checksum: checksum
end

#upload(key, io, checksum: nil, **options) ⇒ Object

Upload the io to the key specified to all services. The upload to the primary service is done synchronously whereas the upload to the mirrors is done asynchronously. If a checksum is provided, all services will ensure a match when the upload has completed or raise an ActiveStorage::IntegrityError.



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# File 'activestorage/lib/active_storage/service/mirror_service.rb', line 45

def upload(key, io, checksum: nil, **options)
  io.rewind
  primary.upload key, io, checksum: checksum, **options
  mirror_later key, checksum: checksum
end