Symlink the resolv.conf around post scripts run

service/lib/agama/network.rb

@@ -46,11 +46,33 @@ def install
       ProxySetup.instance.install
     end
 
+    def link_resolv
+      return unless File.exist?(RESOLV)
+
+      link = File.join(Yast::Installation.destdir, RESOLV)
+      target = File.join(RUN_NM_DIR, File.basename(RESOLV))
+
+      return if File.exist?(link)
+
+      FileUtils.touch RESOLV_FLAG
+      FileUtils.ln_s target, link
+    end
+
+    def unlink_resolv
+      return unless File.exist?(RESOLV_FLAG)
+
+      link = File.join(Yast::Installation.destdir, RESOLV)
+      FileUtils.rm_f link
+      FileUtils.rm_f RESOLV_FLAG
+    end
+
   private
 
     # @return [Logger]
     attr_reader :logger
 
+    RESOLV = "/etc/resolv.conf"
+    RESOLV_FLAG = "/run/agama/manage_resolv"
     ETC_NM_DIR = "/etc/NetworkManager"
     RUN_NM_DIR = "/run/NetworkManager"
     private_constant :ETC_NM_DIR

service/lib/agama/storage/finisher.rb

@@ -27,6 +27,7 @@
 require "agama/with_progress"
 require "agama/helpers"
 require "agama/http"
+require "agama/network"
 require "abstract_method"
 require "fileutils"
 
@@ -261,9 +262,15 @@ def run
 
         # Run the post scripts
         def run_post_scripts
-          require "agama/http"
+          network.link_resolv
           client = Agama::HTTP::Clients::Scripts.new
           client.run("post")
+        ensure
+          network.unlink_resolv
+        end
+
+        def network
+          @network ||= Agama::Network.new(logger)
         end
 
         # Enables the agama-scripts service to run init scripts

service/package/rubygem-agama-yast.changes

@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Thu Mar 20 08:41:23 UTC 2025 - Knut Anderssen <kanderssen@suse.com>
+
+- Symlink the /mnt/etc/resolv.conf to the NetworkManager running
+  one in order to have DNS resolution in the chroot post scripts
+  (bsc#1235617, gh#agama-project/agama#2179).
+
 -------------------------------------------------------------------
 Fri Mar 14 12:34:03 UTC 2025 - Imobach Gonzalez Sosa <igonzalezsosa@suse.com>
 

service/test/agama/network_test.rb

@@ -28,25 +28,29 @@
   subject(:network) { described_class.new(logger) }
 
   let(:logger) { Logger.new($stdout, level: :warn) }
+  let(:targetdir) { File.join(rootdir, "mnt") }
+
+  before do
+    allow(Yast::Installation).to receive(:destdir).and_return(targetdir)
+  end
+
+  after do
+    FileUtils.remove_entry(rootdir)
+  end
 
   describe "#install" do
     let(:rootdir) { Dir.mktmpdir }
+
     let(:etcdir) do
       File.join(rootdir, "etc", "NetworkManager", "system-connections")
     end
-    let(:targetdir) { File.join(rootdir, "mnt") }
     let(:service) { instance_double(Yast2::Systemd::Service, enable: nil) }
 
     before do
-      allow(Yast::Installation).to receive(:destdir).and_return(targetdir)
       allow(Yast2::Systemd::Service).to receive(:find).with("NetworkManager").and_return(service)
       stub_const("Agama::Network::ETC_NM_DIR", etcdir)
     end
 
-    after do
-      FileUtils.remove_entry(rootdir)
-    end
-
     context "when NetworkManager configuration files are present" do
       before do
         FileUtils.mkdir_p(File.join(etcdir, "system-connections"))
@@ -95,4 +99,74 @@
       end
     end
   end
+
+  describe "#link_resolv" do
+    let(:rootdir) { Dir.mktmpdir }
+
+    let(:fixtures) { File.join(FIXTURES_PATH, "root_dir") }
+    let(:resolv_fixture) { File.join(FIXTURES_PATH, "etc", "resolv.conf") }
+    let(:resolv_flag) { File.join(rootdir, "run", "agama", "manage_resolv") }
+    let(:resolv) { File.join(targetdir, "etc", "resolv.conf") }
+
+    before do
+      stub_const("Agama::Network::RESOLV_FLAG", resolv_flag)
+      stub_const("Agama::Network::RUN_NM_DIR", File.join(rootdir, "run", "NetworkManager"))
+      FileUtils.mkdir_p targetdir
+      FileUtils.cp_r(Dir["#{fixtures}/*"], rootdir)
+      FileUtils.cp_r(Dir["#{fixtures}/*"], targetdir)
+    end
+
+    context "when the /etc/resolv.conf exists in the installation destdir" do
+      before do
+        FileUtils.mkdir_p File.join(targetdir, "etc")
+        FileUtils.touch File.join(targetdir, "etc", "resolv.conf")
+      end
+
+      it "does nothing" do
+        expect(FileUtils).to_not receive(:ln_s)
+        network.link_resolv
+      end
+    end
+
+    context "when there is no /etc/resolv.conf in the installation destdir" do
+      it "symlinks it to /run/NetworkManager/resolv.conf" do
+        network.link_resolv
+        expect(File.exist?(resolv)).to eql(true)
+        expect(File.symlink?(resolv)).to eql(true)
+      end
+
+      it "creates a flag indicating that the resolv.conf is managed by Agama" do
+        network.link_resolv
+        expect(File.exist?(resolv_flag)).to eql(true)
+      end
+    end
+  end
+
+  describe "#unlink_resolv" do
+    let(:rootdir) { Dir.mktmpdir }
+
+    let(:fixtures) { File.join(FIXTURES_PATH, "root_dir") }
+    let(:resolv_fixture) { File.join(FIXTURES_PATH, "etc", "resolv.conf") }
+    let(:resolv_flag) { File.join(rootdir, "run", "agama", "manage_resolv") }
+    let(:resolv) { File.join(targetdir, "etc", "resolv.conf") }
+
+    before do
+      stub_const("Agama::Network::RESOLV_FLAG", resolv_flag)
+      stub_const("Agama::Network::RUN_NM_DIR", File.join(rootdir, "run", "NetworkManager"))
+      FileUtils.mkdir_p targetdir
+      FileUtils.cp_r(Dir["#{fixtures}/*"], rootdir)
+      FileUtils.cp_r(Dir["#{fixtures}/*"], targetdir)
+    end
+
+    context "when the /etc/resolv.conf was marked as managed by Agama" do
+      it "removes the /etc/resolv.con symlink from the installation destdir" do
+        network.link_resolv
+        expect(File.exist?(resolv_flag)).to eql(true)
+        expect(File.symlink?(resolv)).to eql(true)
+        network.unlink_resolv
+        expect(File.exist?(resolv)).to eql(false)
+        expect(File.exist?(resolv_flag)).to eql(false)
+      end
+    end
+  end
 end

service/test/agama/storage/manager_test.rb

@@ -22,7 +22,7 @@
 require_relative "../../test_helper"
 require_relative "../with_progress_examples"
 require_relative "../with_issues_examples"
-require_relative "./storage_helpers"
+require_relative "storage_helpers"
 require "agama/dbus/clients/questions"
 require "agama/config"
 require "agama/http"
@@ -59,6 +59,7 @@
     # mock writting config as proposal call can do storage probing, which fails in CI
     allow_any_instance_of(Agama::Storage::Bootloader).to receive(:write_config)
     allow(Agama::HTTP::Clients::Scripts).to receive(:new).and_return(scripts_client)
+    allow(Agama::Network).to receive(:new).and_return(network)
     allow(Yast::Installation).to receive(:destdir).and_return(File.join(tmp_dir, "mnt"))
     stub_const("Agama::Storage::Finisher::CopyLogsStep::SCRIPTS_DIR",
       File.join(tmp_dir, "run", "agama", "scripts"))
@@ -73,6 +74,7 @@
   let(:software) do
     instance_double(Agama::DBus::Clients::Software, selected_product: "ALP")
   end
+  let(:network) { instance_double(Agama::Network, link_resolv: nil, unlink_resolv: nil) }
   let(:bootloader_finish) { instance_double(Bootloader::FinishClient, write: nil) }
   let(:security) { instance_double(Agama::Security, probe: nil, write: nil) }
 
@@ -378,13 +380,16 @@
     let(:devicegraph) { "staging-plain-partitions.yaml" }
 
     it "copy needed files, installs the bootloader, sets up the snapshots, " \
-       "copy logs, runs the post-installation scripts, and umounts the file systems" do
+       "copy logs, symlink resolv.conf, runs the post-installation scripts, " \
+       "unlink resolv.conf, and umounts the file systems" do
       expect(security).to receive(:write)
       expect(copy_files).to receive(:run)
       expect(bootloader_finish).to receive(:write)
       expect(Yast::WFM).to receive(:CallFunction).with("storage_finish", ["Write"])
       expect(Yast::WFM).to receive(:CallFunction).with("snapshots_finish", ["Write"])
+      expect(network).to receive(:link_resolv)
       expect(scripts_client).to receive(:run).with("post")
+      expect(network).to receive(:unlink_resolv)
       expect(Yast::Execute).to receive(:on_target!)
         .with("systemctl", "enable", "agama-scripts", allowed_exitstatus: [0, 1])
       expect(Yast::WFM).to receive(:CallFunction).with("umount_finish", ["Write"])

service/test/fixtures/root_dir/run/NetworkManager/resolv.conf

@@ -0,0 +1,3 @@
+# Generated by NetworkManager
+search default
+nameserver 192.168.100.1