Handle RangeNotSatisfiable for compact index

lib/bundler/fetcher/downloader.rb

@@ -11,10 +11,10 @@ def initialize(connection, redirect_limit)
         @redirect_limit = redirect_limit
       end
 
-      def fetch(uri, options = {}, counter = 0)
+      def fetch(uri, headers = {}, counter = 0)
         raise HTTPError, "Too many redirects" if counter >= redirect_limit
 
-        response = request(uri, options)
+        response = request(uri, headers)
         Bundler.ui.debug("HTTP #{response.code} #{response.message} #{uri}")
 
         case response
@@ -26,7 +26,12 @@ def fetch(uri, options = {}, counter = 0)
             new_uri.user = uri.user
             new_uri.password = uri.password
           end
-          fetch(new_uri, options, counter + 1)
+          fetch(new_uri, headers, counter + 1)
+        when Net::HTTPRequestedRangeNotSatisfiable
+          new_headers = headers.dup
+          new_headers.delete("Range")
+          new_headers["Accept-Encoding"] = "gzip"
+          fetch(uri, new_headers)
         when Net::HTTPRequestEntityTooLarge
           raise FallbackError, response.body
         when Net::HTTPUnauthorized
@@ -38,11 +43,11 @@ def fetch(uri, options = {}, counter = 0)
         end
       end
 
-      def request(uri, options)
+      def request(uri, headers)
         validate_uri_scheme!(uri)
 
         Bundler.ui.debug "HTTP GET #{uri}"
-        req = Net::HTTP::Get.new uri.request_uri, options
+        req = Net::HTTP::Get.new uri.request_uri, headers
         if uri.user
           user = CGI.unescape(uri.user)
           password = uri.password ? CGI.unescape(uri.password) : nil

spec/install/gems/compact_index_spec.rb

@@ -821,6 +821,37 @@ def start
     expect(the_bundle).to include_gems "rack 1.0.0"
   end
 
+  it "performs full update of compact index info cache if range is not satisfiable" do
+    gemfile <<-G
+      source "#{source_uri}"
+      gem 'rack', '0.9.1'
+    G
+
+    rake_info_path = File.join(Bundler.rubygems.user_home, ".bundle", "cache", "compact_index",
+      "localgemserver.test.80.dd34752a738ee965a2a4298dc16db6c5", "info", "rack")
+
+    bundle! :install, :artifice => "compact_index"
+
+    expected_rack_info_content = File.read(rake_info_path)
+
+    # Modify the cache files. We expect them to be reset to the normal ones when we re-run :install
+    File.open(rake_info_path, "w") {|f| f << (expected_rack_info_content + "this is different") }
+
+    # Update the Gemfile so the next install does its normal things
+    gemfile <<-G
+      source "#{source_uri}"
+      gem 'rack', '1.0.0'
+    G
+
+    # The cache files now being longer means the requested range is going to be not satisfiable
+    # Bundler must end up requesting the whole file to fix things up.
+    bundle! :install, :artifice => "compact_index_range_not_satisfiable"
+
+    resulting_rack_info_content = File.read(rake_info_path)
+
+    expect(resulting_rack_info_content).to eq(expected_rack_info_content)
+  end
+
   it "fails gracefully when the source URI has an invalid scheme" do
     install_gemfile <<-G
       source "htps://rubygems.org"

spec/support/artifice/compact_index_range_not_satisfiable.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require File.expand_path("../compact_index", __FILE__)
+
+Artifice.deactivate
+
+class CompactIndexRangeNotSatisfiable < CompactIndexAPI
+  get "/versions" do
+    if env["HTTP_RANGE"]
+      status 416
+    else
+      etag_response do
+        file = tmp("versions.list")
+        file.delete if file.file?
+        file = CompactIndex::VersionsFile.new(file.to_s)
+        file.create(gems)
+        file.contents
+      end
+    end
+  end
+
+  get "/info/:name" do
+    if env["HTTP_RANGE"]
+      status 416
+    else
+      etag_response do
+        gem = gems.find {|g| g.name == params[:name] }
+        CompactIndex.info(gem ? gem.versions : [])
+      end
+    end
+  end
+end
+
+Artifice.activate_with(CompactIndexRangeNotSatisfiable)