Class: ActiveStorage::Service::DiskService

Inherits:
Service
  • Object
show all
Defined in:
lib/active_storage/service/disk_service.rb

Overview

Active Storage Disk Service

Wraps a local disk path as an Active Storage service. See ActiveStorage::Service for the generic API documentation that applies to all services.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(root:, public: false, **options) ⇒ DiskService

Returns a new instance of DiskService.



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

def initialize(root:, public: false, **options)
  @root = root
  @public = public
end

Instance Attribute Details

#root ⇒ Object

Returns the value of attribute root.



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# File 'lib/active_storage/service/disk_service.rb', line 14

def root
  @root
end

Instance Method Details

#compose(source_keys, destination_key) ⇒ Object 



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# File 'lib/active_storage/service/disk_service.rb', line 145

def compose(source_keys, destination_key, **)
  File.open(make_path_for(destination_key), "w") do |destination_file|
    source_keys.each do |source_key|
      File.open(path_for(source_key), "rb") do |source_file|
        IO.copy_stream(source_file, destination_file)
      end
    end
  end
end

#delete(key) ⇒ Object 



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# File 'lib/active_storage/service/disk_service.rb', line 53

def delete(key)
  instrument :delete, key: key do
    File.delete path_for(key)
  rescue Errno::ENOENT
    # Ignore files already deleted
  end
end

#delete_prefixed(prefix) ⇒ Object 



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

def delete_prefixed(prefix)
  instrument :delete_prefixed, prefix: prefix do
    prefix_path = path_for(prefix)

    # File.expand_path (called within path_for) strips trailing slashes.
    # Restore trailing separator if the original prefix had one, so that
    # the glob "prefix/*" matches files inside the directory, not siblings
    # whose names start with the prefix string.
    prefix_path += "/" if prefix.end_with?("/")

    escaped = escape_glob_metacharacters(prefix_path)
    Dir.glob("#{escaped}*").each do |path|
      FileUtils.rm_rf(path)
    end
  end
end

#download(key, &block) ⇒ Object 



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# File 'lib/active_storage/service/disk_service.rb', line 28

def download(key, &block)
  if block_given?
    instrument :streaming_download, key: key do
      stream key, &block
    end
  else
    instrument :download, key: key do
      File.binread path_for(key)
    rescue Errno::ENOENT
      raise ActiveStorage::FileNotFoundError
    end
  end
end

#download_chunk(key, range) ⇒ Object 



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# File 'lib/active_storage/service/disk_service.rb', line 42

def download_chunk(key, range)
  instrument :download_chunk, key: key, range: range do
    File.open(path_for(key), "rb") do |file|
      file.seek range.begin
      file.read range.size
    end
  rescue Errno::ENOENT
    raise ActiveStorage::FileNotFoundError
  end
end

#exist?(key) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_storage/service/disk_service.rb', line 78

def exist?(key)
  instrument :exist, key: key do |payload|
    answer = File.exist? path_for(key)
    payload[:exist] = answer
    answer
  end
end

#headers_for_direct_upload(key, content_type:) ⇒ Object 



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# File 'lib/active_storage/service/disk_service.rb', line 106

def headers_for_direct_upload(key, content_type:, **)
  { "Content-Type" => content_type }
end

#path_for(key) ⇒ Object

Every filesystem operation in DiskService resolves paths through this method (or through make_path_for, which delegates here). This is the primary filesystem security check: all path-traversal protection is enforced here. New methods that touch the filesystem MUST use path_for or make_path_for -- never construct paths from root directly.



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# File 'lib/active_storage/service/disk_service.rb', line 114

def path_for(key) # :nodoc:
  if key.blank?
    raise ActiveStorage::InvalidKeyError, "key is blank"
  end

  # Reject keys with dot segments as defense in depth. This prevents path traversal both outside
  # and within the storage root. The root containment check below is a more fundamental check on
  # path traversal outside of the disk service root.
  begin
    if key.split("/").intersect?(%w[. ..])
      raise ActiveStorage::InvalidKeyError, "key has path traversal segments"
    end
  rescue Encoding::CompatibilityError
    raise ActiveStorage::InvalidKeyError, "key has incompatible encoding"
  end

  begin
    path = File.expand_path(File.join(root, folder_for(key), key))
  rescue ArgumentError
    # ArgumentError catches null bytes
    raise ActiveStorage::InvalidKeyError, "key is an invalid string"
  end

  # The resolved path must be inside the root directory.
  unless path.start_with?(File.expand_path(root) + "/")
    raise ActiveStorage::InvalidKeyError, "key is outside of disk service root"
  end

  path
end

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



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# File 'lib/active_storage/service/disk_service.rb', line 21

def upload(key, io, checksum: nil, **)
  instrument :upload, key: key, checksum: checksum do
    IO.copy_stream(io, make_path_for(key))
    ensure_integrity_of(key, checksum) if checksum
  end
end

#url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:, custom_metadata: {}) ⇒ Object 



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# File 'lib/active_storage/service/disk_service.rb', line 86

def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:, custom_metadata: {})
  instrument :url, key: key do |payload|
    verified_token_with_expiration = ActiveStorage.verifier.generate(
      {
        key: key,
        content_type: content_type,
        content_length: content_length,
        checksum: checksum,
        service_name: name
      },
      expires_in: expires_in,
      purpose: :blob_token
    )

    url_helpers.update_rails_disk_service_url(verified_token_with_expiration, url_options).tap do |generated_url|
      payload[:url] = generated_url
    end
  end
end