Merge pull request #5123 from chef/lcg/resolv-replace

replace glibc resolver with ruby resolver

5 files changed, 43 insertions, 0 deletions

diff --git a/lib/chef/application.rb b/lib/chef/application.rb
index f8df71f723..6c2fc8b11b 100644
--- a/lib/chef/application.rb
+++ b/lib/chef/application.rb
@@ -28,6 +28,10 @@ require "mixlib/cli"
 require "tmpdir"
 require "rbconfig"
 require "chef/application/exit_code"
+require "resolv"
+# on linux, we replace the glibc resolver with the ruby resolv library, which
+# supports reloading.
+require "resolv-replace" if RbConfig::CONFIG["host_os"] =~ /linux/
 
 class Chef
   class Application
diff --git a/lib/chef/provider/file.rb b/lib/chef/provider/file.rb
index 7f85085eeb..bb0762ceb7 100644
--- a/lib/chef/provider/file.rb
+++ b/lib/chef/provider/file.rb
@@ -154,6 +154,7 @@ class Chef
         do_contents_changes
         do_acl_changes
         do_selinux
+        do_resolv_conf_fixup
         load_resource_attributes_from_file(@new_resource)
       end
 
@@ -445,6 +446,13 @@ class Chef
         end
       end
 
+      def do_resolv_conf_fixup
+        # reload /etc/resolv.conf after we edit it -- only on linux -- and see lib/chef/application.rb
+        if new_resource.path == "/etc/resolv.conf" && RbConfig::CONFIG["host_os"] =~ /linux/
+          Resolv::DefaultResolver.replace_resolvers [Resolv::DNS.new("/etc/resolv.conf")]
+        end
+      end
+
       def do_acl_changes
         if access_controls.requires_changes?
           converge_by(access_controls.describe_changes) do
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 2f6747c9af..44a599436c 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -152,6 +152,8 @@ RSpec.configure do |config|
   config.filter_run_excluding :unix_only => true unless unix?
   config.filter_run_excluding :aix_only => true unless aix?
   config.filter_run_excluding :debian_family_only => true unless debian_family?
+  config.filter_run_excluding :linux_only => true unless linux?
+  config.filter_run_excluding :non_linux_only => true if linux?
   config.filter_run_excluding :supports_cloexec => true unless supports_cloexec?
   config.filter_run_excluding :selinux_only => true unless selinux_enabled?
   config.filter_run_excluding :requires_root => true unless root?
diff --git a/spec/support/platform_helpers.rb b/spec/support/platform_helpers.rb
index 9ba56a15e3..783429161a 100644
--- a/spec/support/platform_helpers.rb
+++ b/spec/support/platform_helpers.rb
@@ -138,6 +138,10 @@ def freebsd?
   !!(RUBY_PLATFORM =~ /freebsd/)
 end
 
+def linux?
+  !!(RUBY_PLATFORM =~ /linux/)
+end
+
 def debian_family?
   !!(ohai[:platform_family] == "debian")
 end
diff --git a/spec/support/shared/unit/provider/file.rb b/spec/support/shared/unit/provider/file.rb
index cb539ffbc3..ee3438da70 100644
--- a/spec/support/shared/unit/provider/file.rb
+++ b/spec/support/shared/unit/provider/file.rb
@@ -683,6 +683,31 @@ shared_examples_for Chef::Provider::File do
       end
     end
 
+    context "do_resolv_conf_fixup" do
+      %w{/resolv.conf /etc/resolv.con /etc/foo/resolv.conf /c/resolv.conf}.each do |path|
+        context "when managing #{path}" do
+          let(:resource_path) { path }
+          it "does not reload the nameservers" do
+            expect(Resolv::DefaultResolver).not_to receive(:replace_resolvers)
+            provider.send(:do_resolv_conf_fixup)
+          end
+        end
+      end
+      context "when managing /etc/resolv.conf", linux_only: true do
+        let(:resource_path) { "/etc/resolv.conf" }
+        it "reloads the nameservers on linux" do
+          expect(Resolv::DefaultResolver).to receive(:replace_resolvers)
+          provider.send(:do_resolv_conf_fixup)
+        end
+      end
+      context "when managing /etc/resolv.conf", non_linux_only: true do
+        let(:resource_path) { "/etc/resolv.conf" }
+        it "does not reload the nameservers on non-linux" do
+          expect(Resolv::DefaultResolver).not_to receive(:replace_resolvers)
+          provider.send(:do_resolv_conf_fixup)
+        end
+      end
+    end
   end
 
   context "action delete" do