Make storage adapters report their protocol string (#974)

* Make storage adapters report their protocol string

Having this available will ease writing tests for systems that use multiple storage adapters.
The fedora storage adapter already does this.

* Refactor to use protocol instance method

lib/valkyrie/specs/shared_specs/storage_adapter.rb

@@ -12,6 +12,7 @@ class Valkyrie::Specs::CustomResource < Valkyrie::Resource
     Valkyrie::Specs.send(:remove_const, :CustomResource)
   end
   subject { storage_adapter }
+  it { is_expected.to respond_to(:protocol) }
   it { is_expected.to respond_to(:handles?).with_keywords(:id) }
   it { is_expected.to respond_to(:find_by).with_keywords(:id) }
   it { is_expected.to respond_to(:delete).with_keywords(:id) }

lib/valkyrie/storage/disk.rb

@@ -3,6 +3,8 @@ module Valkyrie::Storage
   # Implements the DataMapper Pattern to store binary data on disk
   class Disk
     attr_reader :base_path, :path_generator, :file_mover
+    PROTOCOL = 'disk://'
+
     def initialize(base_path:, path_generator: BucketedStorage, file_mover: FileUtils.method(:mv))
       @base_path = Pathname.new(base_path.to_s)
       @path_generator = path_generator.new(base_path: base_path)
@@ -18,13 +20,13 @@ def upload(file:, original_filename:, resource: nil, **_extra_arguments)
       new_path = path_generator.generate(resource: resource, file: file, original_filename: original_filename)
       FileUtils.mkdir_p(new_path.parent)
       file_mover.call(file.path, new_path)
-      find_by(id: Valkyrie::ID.new("disk://#{new_path}"))
+      find_by(id: Valkyrie::ID.new("#{protocol}#{new_path}"))
     end
 
     # @param id [Valkyrie::ID]
     # @return [Boolean] true if this adapter can handle this type of identifer
     def handles?(id:)
-      id.to_s.start_with?("disk://#{base_path}")
+      id.to_s.start_with?("#{protocol}#{base_path}")
     end
 
     # @param feature [Symbol] Feature to test for.
@@ -33,8 +35,13 @@ def supports?(_feature)
       false
     end
 
+    # @return [String] identifier prefix
+    def protocol
+      PROTOCOL
+    end
+
     def file_path(id)
-      id.to_s.gsub(/^disk:\/\//, '')
+      id.to_s.gsub(/^#{Regexp.escape(protocol)}/, '')
     end
 
     # Return the file associated with the given identifier

lib/valkyrie/storage/fedora.rb

@@ -27,7 +27,7 @@ def initialize(connection:, base_path: "/", fedora_version: Valkyrie::Persistenc
     # @param id [Valkyrie::ID]
     # @return [Boolean] true if this adapter can handle this type of identifer
     def handles?(id:)
-      id.to_s.start_with?(PROTOCOL)
+      id.to_s.start_with?(protocol)
     end
 
     # @param feature [Symbol] Feature to test for.
@@ -41,6 +41,11 @@ def supports?(feature)
       false
     end
 
+    # @return [String] identifier prefix
+    def protocol
+      PROTOCOL
+    end
+
     # Return the file associated with the given identifier
     # @param id [Valkyrie::ID]
     # @return [Valkyrie::StorageAdapter::StreamFile]
@@ -63,7 +68,7 @@ def upload(file:, original_filename:, resource:, content_type: "application/octe
       # Fedora 6 auto versions, so check to see if there's a version for this
       # initial upload. If not, then mint one (fedora 4/5)
       version_id = current_version_id(id: valkyrie_identifier(uri: identifier)) || mint_version(identifier, latest_version(identifier))
-      perform_find(id: Valkyrie::ID.new(identifier.to_s.sub(/^.+\/\//, PROTOCOL)), version_id: version_id)
+      perform_find(id: Valkyrie::ID.new(identifier.to_s.sub(/^.+\/\//, protocol)), version_id: version_id)
     end
 
     # @param id [Valkyrie::ID] ID of the Valkyrie::StorageAdapter::StreamFile to
@@ -79,7 +84,7 @@ def upload_version(id:, file:)
       end
       upload_file(fedora_uri: uri, io: file)
       version_id = mint_version(uri, latest_version(uri))
-      perform_find(id: Valkyrie::ID.new(uri.to_s.sub(/^.+\/\//, PROTOCOL)), version_id: version_id)
+      perform_find(id: Valkyrie::ID.new(uri.to_s.sub(/^.+\/\//, protocol)), version_id: version_id)
     end
 
     # @param id [Valkyrie::ID]
@@ -201,12 +206,12 @@ def io
     # Translate the Valkrie ID into a URL for the fedora file
     # @return [RDF::URI]
     def fedora_identifier(id:)
-      identifier = id.to_s.sub(PROTOCOL, "#{connection.http.scheme}://")
+      identifier = id.to_s.sub(protocol, "#{connection.http.scheme}://")
       RDF::URI(identifier)
     end
 
     def valkyrie_identifier(uri:)
-      id = uri.to_s.sub("http://", PROTOCOL)
+      id = uri.to_s.sub("http://", protocol)
       Valkyrie::ID.new(id)
     end
 

lib/valkyrie/storage/memory.rb

@@ -6,6 +6,8 @@ module Valkyrie::Storage
   #   in cases where you want to preserve real data
   class Memory
     attr_reader :cache
+    PROTOCOL = 'memory://'
+
     def initialize
       @cache = {}
     end
@@ -16,7 +18,7 @@ def initialize
     # @param _extra_arguments [Hash] additional arguments which may be passed to other adapters
     # @return [Valkyrie::StorageAdapter::StreamFile]
     def upload(file:, original_filename:, resource: nil, **_extra_arguments)
-      identifier = Valkyrie::ID.new("memory://#{resource.id}")
+      identifier = Valkyrie::ID.new("#{protocol}#{resource.id}")
       version_id = Valkyrie::ID.new("#{identifier}##{SecureRandom.uuid}")
       cache[identifier] ||= {}
       cache[identifier][:current] = Valkyrie::StorageAdapter::StreamFile.new(id: identifier, io: file, version_id: version_id)
@@ -67,7 +69,7 @@ def find_by(id:)
     # @param id [Valkyrie::ID]
     # @return [Boolean] true if this adapter can handle this type of identifer
     def handles?(id:)
-      id.to_s.start_with?("memory://")
+      id.to_s.start_with?(protocol)
     end
 
     # @param feature [Symbol] Feature to test for.
@@ -83,6 +85,11 @@ def supports?(feature)
       end
     end
 
+    # @return [String] identifier prefix
+    def protocol
+      PROTOCOL
+    end
+
     def id_and_version(id)
       id, version = id.to_s.split("#")
       [Valkyrie::ID.new(id), version]

lib/valkyrie/storage/versioned_disk.rb

@@ -7,6 +7,8 @@ module Valkyrie::Storage
   # with "deletionmarker" in the name of the file.
   class VersionedDisk
     attr_reader :base_path, :path_generator, :file_mover
+    PROTOCOL = 'versiondisk://'
+
     def initialize(base_path:, path_generator: ::Valkyrie::Storage::Disk::BucketedStorage, file_mover: FileUtils.method(:cp))
       @base_path = Pathname.new(base_path.to_s)
       @path_generator = path_generator.new(base_path: base_path)
@@ -26,7 +28,7 @@ def upload(file:, original_filename:, resource: nil, paused: false, **extra_argu
       return sleep(0.001) && upload(file: file, original_filename: original_filename, resource: resource, paused: true, **extra_arguments) if !paused && File.exist?(new_path)
       FileUtils.mkdir_p(new_path.parent)
       file_mover.call(file.try(:path) || file.try(:disk_path), new_path)
-      find_by(id: Valkyrie::ID.new("versiondisk://#{new_path}"))
+      find_by(id: Valkyrie::ID.new("#{protocol}#{new_path}"))
     end
 
     def current_timestamp
@@ -50,13 +52,13 @@ def upload_version(id:, file:, paused: false)
       return sleep(0.001) && upload_version(id: id, file: file, paused: true) if !paused && File.exist?(new_path)
       FileUtils.mkdir_p(new_path.parent)
       file_mover.call(file.try(:path) || file.try(:disk_path), new_path)
-      find_by(id: Valkyrie::ID.new("versiondisk://#{new_path}"))
+      find_by(id: Valkyrie::ID.new("#{protocol}#{new_path}"))
     end
 
     # @param id [Valkyrie::ID]
     # @return [Boolean] true if this adapter can handle this type of identifer
     def handles?(id:)
-      id.to_s.start_with?("versiondisk://#{base_path}")
+      id.to_s.start_with?("#{protocol}#{base_path}")
     end
 
     # @param feature [Symbol] Feature to test for.
@@ -66,6 +68,11 @@ def supports?(feature)
       false
     end
 
+    # @return [String] identifier prefix
+    def protocol
+      PROTOCOL
+    end
+
     # Return the file associated with the given identifier
     # @param id [Valkyrie::ID]
     # @return [Valkyrie::StorageAdapter::File]
@@ -95,7 +102,7 @@ def delete(id:)
     # @return [Array<Valkyrie::StorageAdapter::File>]
     def find_versions(id:)
       version_files(id: id).select { |x| !x.to_s.include?("deletionmarker") }.map do |file|
-        find_by(id: Valkyrie::ID.new("versiondisk://#{file}"))
+        find_by(id: Valkyrie::ID.new("#{protocol}#{file}"))
       end
     end
 
@@ -106,7 +113,7 @@ def version_files(id:)
     end
 
     def file_path(version_id)
-      version_id.to_s.gsub(/^versiondisk:\/\//, '')
+      version_id.to_s.gsub(/^#{Regexp.escape(protocol)}/, '')
     end
 
     # @return VersionId A VersionId value that's resolved a current reference,
@@ -128,6 +135,10 @@ def initialize(id)
         @id = id
       end
 
+      def protocol
+        PROTOCOL
+      end
+
       def current_reference_id
         self.class.new(Valkyrie::ID.new(string_id.gsub(version, "current")))
       end
@@ -139,13 +150,13 @@ def resolve_current
       end
 
       def file_path
-        @file_path ||= string_id.gsub(/^versiondisk:\/\//, '')
+        @file_path ||= string_id.gsub(/^#{Regexp.escape(protocol)}/, '')
       end
 
       def version_files
         root = Pathname.new(file_path)
         root.parent.children.select { |file| file.basename.to_s.end_with?(filename) }.sort.reverse.map do |file|
-          VersionId.new(Valkyrie::ID.new("versiondisk://#{file}"))
+          VersionId.new(Valkyrie::ID.new("#{protocol}#{file}"))
         end
       end