Prefix_delete for cellar

lib/active_storage/service/cellar_service.rb

@@ -12,12 +12,11 @@ module ActiveStorage
     end
 
     def download(key)
+      # TODO: error handling
       if block_given?
         instrument :streaming_download, key: key do
           http_start do |http|
-            request = Net::HTTP::Get.new(URI::join(@endpoint, "/#{key}"))
+            http.request(get_request(key)) do |response|
-            sign(request, key)
-            http.request(request) do |response|
               response.read_body do |chunk|
                 yield(chunk.force_encoding(Encoding::BINARY))
               end
@@ -27,9 +26,7 @@ module ActiveStorage
       else
         instrument :download, key: key do
           http_start do |http|
-            request = Net::HTTP::Get.new(URI::join(@endpoint, "/#{key}"))
+            response = http.request(get_request(key))
-            sign(request, key)
-            response = http.request(request)
             if response.is_a?(Net::HTTPSuccess)
               response.body.force_encoding(Encoding::BINARY)
             end
@@ -39,11 +36,23 @@ module ActiveStorage
     end
 
     def delete(key)
+      # TODO: error handling
       instrument :delete, key: key do
         http_start do |http|
-          request = Net::HTTP::Delete.new(URI::join(@endpoint, "/#{key}"))
+          perform_delete(http, key)
-          sign(request, key)
+        end
-          http.request(request)
+      end
+    end
+
+    def delete_prefixed(prefix)
+      # TODO: error handling
+      # TODO: handle pagination if more than 1000 keys
+      instrument :delete_prefixed, prefix: prefix do
+        http_start do |http|
+          list_prefixed(http, prefix).each do |key|
+            # TODO: use bulk delete instead
+            perform_delete(http, key)
+          end
         end
       end
     end
@@ -112,5 +121,47 @@ module ActiveStorage
                        "#{canonicalized_amz_headers}#{canonicalized_resource}"
       Base64.encode64(OpenSSL::HMAC.digest(OpenSSL::Digest.new('sha1'), @secret_access_key, string_to_sign)).strip
     end
+
+    def list_prefixed(http, prefix)
+      request = Net::HTTP::Get.new(URI::join(@endpoint, "/?list-type=2&prefix=#{prefix}"))
+      sign(request, "")
+      response = http.request(request)
+      if response.is_a?(Net::HTTPSuccess)
+        parse_bucket_listing(response.body)
+      end
+    end
+
+    def parse_bucket_listing(bucket_listing_xml)
+      doc = Nokogiri::XML(bucket_listing_xml)
+      doc
+        .xpath('//xmlns:Contents/xmlns:Key')
+        .map{ |k| k.text }
+    end
+
+    def get_request(key)
+      request = Net::HTTP::Get.new(URI::join(@endpoint, "/#{key}"))
+      sign(request, key)
+      request
+    end
+
+    def bulk_deletion_request_body(keys)
+      builder = Nokogiri::XML::Builder.new(:encoding => 'UTF-8') do |xml|
+        xml.Delete do
+          xml.Quiet("true")
+          keys.each do |k|
+            xml.Object do
+              xml.Key(k)
+            end
+          end
+        end
+      end
+      builder.to_xml
+    end
+
+    def perform_delete(http, key)
+      request = Net::HTTP::Delete.new(URI::join(@endpoint, "/#{key}"))
+      sign(request, key)
+      http.request(request)
+    end
   end
 end

spec/lib/active_storage/service/cellar_service_spec.rb

@@ -112,4 +112,55 @@ describe 'CellarService' do
       )
     end
   end
+
+  describe 'parse_bucket_listing' do
+    let(:response) do
+      '<ListBucketResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
+         <Name>example-bucket</Name>
+         <Prefix></Prefix>
+         <KeyCount>2</KeyCount>
+         <MaxKeys>1000</MaxKeys>
+         <Delimiter>/</Delimiter>
+         <IsTruncated>false</IsTruncated>
+         <Contents>
+           <Key>sample1.jpg</Key>
+           <LastModified>2011-02-26T01:56:20.000Z</LastModified>
+           <ETag>&quot;bf1d737a4d46a19f3bced6905cc8b902&quot;</ETag>
+           <Size>142863</Size>
+           <StorageClass>STANDARD</StorageClass>
+         </Contents>
+         <Contents>
+           <Key>sample2.jpg</Key>
+           <LastModified>2011-02-26T01:56:20.000Z</LastModified>
+           <ETag>&quot;bf1d737a4d46a19f3bced6905cc8b902&quot;</ETag>
+           <Size>142863</Size>
+           <StorageClass>STANDARD</StorageClass>
+         </Contents>
+       </ListBucketResult>'
+    end
+
+    subject { cellar_service.send(:parse_bucket_listing, response) }
+
+    it { is_expected.to eq(["sample1.jpg", "sample2.jpg"]) }
+  end
+
+  describe 'bulk_deletion_request_body' do
+    let(:expected_response) do
+      '<?xml version="1.0" encoding="UTF-8"?>
+<Delete>
+  <Quiet>true</Quiet>
+  <Object>
+    <Key>chapi</Key>
+  </Object>
+  <Object>
+    <Key>chapo</Key>
+  </Object>
+</Delete>
+'
+    end
+
+    subject { cellar_service.send(:bulk_deletion_request_body, ['chapi', 'chapo']) }
+
+    it { is_expected.to eq(expected_response) }
+  end
 end