Merge pull request #335 from samvera-labs/working-on-valkyrie-underst…

…anding-part-2

Working on valkyrie understanding part 2

lib/valkyrie/storage_adapter.rb

@@ -22,8 +22,11 @@ def unregister(short_name)
       # Find the adapter associated with the provided short name
       # @param short_name [Symbol]
       # @return [Valkyrie::StorageAdapter]
+      # @raise Valkyrie::StorageAdapter::AdapterNotFoundError when we are unable to find the named adapter
       def find(short_name)
-        storage_adapters[short_name]
+        storage_adapters.fetch(short_name)
+      rescue KeyError
+        raise "Unable to find #{self} with short_name of #{short_name.inspect}. Registered adapters are #{storage_adapters.keys.inspect}"
       end
 
       # Search through all registered storage adapters until it finds one that
@@ -37,15 +40,18 @@ def find_by(id:)
       end
 
       # Search through all registered storage adapters until it finds one that
-      # can handle the passed in identifier.  The call delete on that adapter
+      # can handle the passed in identifier.  Then call delete on that adapter
       # with the given identifier.
       # @param id [Valkyrie::ID]
       def delete(id:)
         adapter_for(id: id).delete(id: id)
       end
 
       # Return the registered storage adapter which handles the given ID.
+      # @param id [Valkyrie::ID]
+      # @return [Valkyrie::StorageAdapter]
       def adapter_for(id:)
+        # TODO: Determine the appropriate response when we have an unhandled :id
         storage_adapters.values.find do |storage_adapter|
           storage_adapter.handles?(id: id)
         end

spec/valkyrie/storage_adapter_spec.rb

@@ -15,6 +15,14 @@
     end
   end
 
+  describe '.find' do
+    context "with an unregistered adapter" do
+      it "raises a #{described_class}::AdapterNotFoundError" do
+        expect { described_class.find(:obviously_missing) }.to raise_error(RuntimeError, /:obviously_missing/)
+      end
+    end
+  end
+
   describe ".find_by" do
     it "delegates down to its storage_adapters to find one which handles the given identifier" do
       file = instance_double(Valkyrie::StorageAdapter::StreamFile, id: "yo")