updater.rb in rubygems-update-2.7.0

- old
+ new

@@ -1,9 +1,9 @@
 # frozen_string_literal: true
-require "fileutils"
+
+require "bundler/vendored_fileutils"
 require "stringio"
-require "tmpdir"
 require "zlib"
 
 module Bundler
   class CompactIndexClient
     class Updater
@@ -20,10 +20,11 @@
         end
       end
 
       def initialize(fetcher)
         @fetcher = fetcher
+        require "tmpdir"
       end
 
       def update(local_path, remote_path, retrying = nil)
         headers = {}
 
@@ -32,11 +33,18 @@
 
           # first try to fetch any new bytes on the existing file
           if retrying.nil? && local_path.file?
             FileUtils.cp local_path, local_temp_path
             headers["If-None-Match"] = etag_for(local_temp_path)
-            headers["Range"] = "bytes=#{local_temp_path.size}-"
+            headers["Range"] =
+              if local_temp_path.size.nonzero?
+                # Subtract a byte to ensure the range won't be empty.
+                # Avoids 416 (Range Not Satisfiable) responses.
+                "bytes=#{local_temp_path.size - 1}-"
+              else
+                "bytes=#{local_temp_path.size}-"
+              end
           else
             # Fastly ignores Range when Accept-Encoding: gzip is set
             headers["Accept-Encoding"] = "gzip"
           end
 
@@ -46,16 +54,19 @@
           content = response.body
           if response["Content-Encoding"] == "gzip"
             content = Zlib::GzipReader.new(StringIO.new(content)).read
           end
 
-          mode = response.is_a?(Net::HTTPPartialContent) ? "a" : "w"
           SharedHelpers.filesystem_access(local_temp_path) do
-            local_temp_path.open(mode) {|f| f << content }
+            if response.is_a?(Net::HTTPPartialContent) && local_temp_path.size.nonzero?
+              local_temp_path.open("a") {|f| f << slice_body(content, 1..-1) }
+            else
+              local_temp_path.open("w") {|f| f << content }
+            end
           end
 
-          response_etag = response["ETag"].gsub(%r{\AW/}, "")
+          response_etag = (response["ETag"] || "").gsub(%r{\AW/}, "")
           if etag_for(local_temp_path) == response_etag
             SharedHelpers.filesystem_access(local_path) do
               FileUtils.mv(local_temp_path, local_path)
             end
             return nil
@@ -72,16 +83,24 @@
       def etag_for(path)
         sum = checksum_for_file(path)
         sum ? %("#{sum}") : nil
       end
 
+      def slice_body(body, range)
+        if body.respond_to?(:byteslice)
+          body.byteslice(range)
+        else # pre-1.9.3
+          body.unpack("@#{range.first}a#{range.end + 1}").first
+        end
+      end
+
       def checksum_for_file(path)
         return nil unless path.file?
         # This must use IO.read instead of Digest.file().hexdigest
         # because we need to preserve \n line endings on windows when calculating
         # the checksum
         SharedHelpers.filesystem_access(path, :read) do
-          Digest::MD5.hexdigest(IO.read(path))
+          SharedHelpers.digest(:MD5).hexdigest(IO.read(path))
         end
       end
     end
   end
 end