[windows] Add option to support EXE Agent installer (#410)

* The EXE installer handles per-user to per-machine upgrades gracefully, including edges cases that the present cookbook can't reasonably handle on its own. For this reason, we add the option to use the exe installer when needed (i.e. for upgrades from Agent <= 5.10.1 to Agent >= 5.12.0). * The URL to the latest installer changes in 5.12.0 from `ddagent-cli` to `ddagent-cli-latest` so that unattended upgrades don't make chef runs fail. Reflect this here. The new URLs work only since 5.12.0, so this change should only be released once the 5.12.0 installers (msi and exe) are generally available at these URLs. * Made some changes on the package removal to handle `windows` >= 1.39 more gracefully. Updated the spec tests assuming they run on Chef >= 12.6. This should be removed (and the whole recipe should be cleaned up) when we stop supporting Chef < 12.6 on Windows. * Added related documentation.
DataDog · Mar 23, 2017 · 3f6435b · 3f6435b
1 parent 05ba57d
commit 3f6435b
Showing 5 changed files with 97 additions and 20 deletions.
diff --git a/README.md b/README.md
@@ -66,10 +66,20 @@ dd-agent
 --------
 Installs the Datadog agent on the target system, sets the API key, and start the service to report on the local system metrics
 
-**Note for Windows**: With Chef >= 12.6 _and_ the `windows` cookbook >= 1.39.0, Agent upgrades are known to fail.
-For Chef>=12.6 users on Windows, we recommend pinning the `windows` cookbook to a lower version (`~> 1.38.0` for instance).
-If that's not an option, a known workaround is to use the `remove-dd-agent` recipe (since the `2.5.0` version of the present cookbook) to uninstall the Agent
-prior to any Agent upgrade.
+**Notes for Windows**:
+
+* With Chef >= 12.6 _and_ the `windows` cookbook >= 1.39.0, Agent upgrades are known to fail.
+  For Chef>=12.6 users on Windows, we recommend pinning the `windows` cookbook to a lower version (`~> 1.38.0` for instance).
+
+  If that's not an option, a known workaround is to use the `remove-dd-agent` recipe (since the `2.5.0` version of the present cookbook) to uninstall the Agent
+  prior to any Agent upgrade.
+
+* Because of changes in the Windows Agent packaging and install in version 5.12.0, when upgrading the Agent from versions <= 5.10.1 to versions >= 5.12.0,
+  please set the `windows_agent_use_exe` attribute to `true`.
+
+  Once the upgrade is complete, you can leave the attribute to its default value (`false`).
+
+  For more information on these Windows packaging changes, see the related [docs on the dd-agent wiki](https://github.com/DataDog/dd-agent/wiki/Windows-Agent-Installation).
 
 dd-handler
 ----------

diff --git a/attributes/default.rb b/attributes/default.rb
@@ -111,6 +111,13 @@
 # Expected checksum to validate correct agent installer is downloaded (Windows only)
 default['datadog']['windows_agent_checksum'] = nil
 
+# Set to `true` to use the EXE installer on Windows, recommended to gracefully handle upgrades from per-user
+# to per-machine installs on most environments. We recommend setting this option to `true` for Agent upgrades from
+# versions <= 5.10.1 to versions >= 5.12.0.
+# The EXE installer exists since Agent release 5.12.0
+# If you're already using version >= 5.12.0 of the Agent, leave this to false.
+default['datadog']['windows_agent_use_exe'] = false
+
 # Values that differ on Windows
 # The location of the config folder (containing conf.d)
 # The name of the dd agent service

diff --git a/recipes/_install-windows.rb b/recipes/_install-windows.rb
@@ -24,29 +24,66 @@
     node['datadog']['agent_version']
   end
 
-# If no version is specified, select the latest package
-dd_agent_msi = dd_agent_version ? "ddagent-cli-#{dd_agent_version}.msi" : 'ddagent-cli.msi'
-temp_file = ::File.join(Chef::Config[:file_cache_path], 'ddagent-cli.msi')
+# If no version is specified, select the latest package.
+# The latest package basename is `ddagent-cli-latest` since Agent version 5.12.0
+dd_agent_installer_basename = dd_agent_version ? "ddagent-cli-#{dd_agent_version}" : 'ddagent-cli-latest'
+temp_file_basename = ::File.join(Chef::Config[:file_cache_path], 'ddagent-cli')
+
+if node['datadog']['windows_agent_use_exe']
+  dd_agent_installer = "#{dd_agent_installer_basename}.exe"
+  temp_file = "#{temp_file_basename}.exe"
+  installer_type = :custom
+  install_options = '/q'
+else
+  dd_agent_installer = "#{dd_agent_installer_basename}.msi"
+  temp_file = "#{temp_file_basename}.msi"
+  installer_type = :msi
+  # Agent >= 5.12.0 installs per-machine by default, but specifying ALLUSERS=1 shouldn't affect the install
+  install_options = '/norestart ALLUSERS=1'
+end
+
+# Use a separate resource without a `source` so that it looks in the Registry to find the MSI to use
+# for the package removal
+# On Chef >= 12.6, we have to use the `package` resource instead of `windows_package` to allow not specifying a source
+# (this is related to the way the windows cookbook changes the provider of `windows_package` depending on the
+# version of Chef, and to improvements on the `package` resource made in Chef 12.6)
+# FIXME: when we remove Chef < 12.6 support on Windows, which should allow using core resources only
+use_windows_package_resource = Gem::Version.new(Chef::VERSION) < Gem::Version.new('12.6.0')
+if use_windows_package_resource
+  windows_package 'Datadog Agent removal' do
+    package_name 'Datadog Agent'
+    action :nothing
+  end
+else
+  package 'Datadog Agent removal' do
+    package_name 'Datadog Agent'
+    action :nothing
+  end
+end
 
 package_retries = node['datadog']['agent_package_retries']
 package_retry_delay = node['datadog']['agent_package_retry_delay']
 
 # Download the installer to a temp location
 remote_file temp_file do
-  source node['datadog']['windows_agent_url'] + dd_agent_msi
+  source node['datadog']['windows_agent_url'] + dd_agent_installer
   checksum node['datadog']['windows_agent_checksum'] if node['datadog']['windows_agent_checksum']
   retries package_retries unless package_retries.nil?
   retry_delay package_retry_delay unless package_retry_delay.nil?
   # As of v1.37, the windows cookbook doesn't upgrade the package if a newer version is downloaded
   # As a workaround uninstall the package first if a new MSI is downloaded
-  notifies :remove, 'windows_package[Datadog Agent]', :immediately
+  if use_windows_package_resource
+    notifies :remove, 'windows_package[Datadog Agent removal]', :immediately
+  else
+    notifies :remove, 'package[Datadog Agent removal]', :immediately
+  end
 end
 
 # Install the package
 windows_package 'Datadog Agent' do # ~FC009
   source temp_file
-  installer_type :msi
-  options '/norestart ALLUSERS=1'
+  installer_type installer_type
+  options install_options
   action :install
   success_codes [0, 3010]
 end
diff --git a/spec/dd-agent_spec.rb b/spec/dd-agent_spec.rb
@@ -144,7 +144,7 @@ def set_env_var(name, value)
     end
 
     context 'on Windows' do
-      cached(:chef_run)  do
+      cached(:chef_run) do
         set_env_var('ProgramData', 'C:\ProgramData')
         ChefSpec::SoloRunner.new(
           :platform => 'windows',
@@ -155,7 +155,25 @@ def set_env_var(name, value)
         end.converge described_recipe
       end
 
-      it_behaves_like 'windows Datadog Agent'
+      it_behaves_like 'windows Datadog Agent', :msi
+    end
+
+    context 'on Windows with EXE installer' do
+      cached(:chef_run) do
+        set_env_var('ProgramData', 'C:\ProgramData')
+        ChefSpec::SoloRunner.new(
+          :platform => 'windows',
+          :version => '2012R2',
+          :file_cache_path => 'C:/chef/cache'
+        ) do |node|
+          node.set['datadog'] = {
+            'api_key' => 'somethingnotnil',
+            'windows_agent_use_exe' => true
+          }
+        end.converge described_recipe
+      end
+
+      it_behaves_like 'windows Datadog Agent', :exe
     end
   end
 
@@ -231,7 +249,7 @@ def set_env_var(name, value)
 
       temp_file = ::File.join('C:/chef/cache', 'ddagent-cli.msi')
 
-      it_behaves_like 'windows Datadog Agent'
+      it_behaves_like 'windows Datadog Agent', :msi
       # remote_file source gets converted to an array, so we need to do
       # some tricky things to be able to regex against it
       # Relevant: http://stackoverflow.com/a/12325983
@@ -286,7 +304,7 @@ def set_env_var(name, value)
 
       temp_file = ::File.join('C:/chef/cache', 'ddagent-cli.msi')
 
-      it_behaves_like 'windows Datadog Agent'
+      it_behaves_like 'windows Datadog Agent', :msi
       # remote_file source gets converted to an array, so we need to do
       # some tricky things to be able to regex against it
       # Relevant: http://stackoverflow.com/a/12325983

diff --git a/spec/shared_examples.rb b/spec/shared_examples.rb
@@ -72,20 +72,25 @@
   end
 end
 
-shared_examples_for 'windows Datadog Agent' do
+shared_examples_for 'windows Datadog Agent' do |installer_extension|
   it_behaves_like 'common windows resources'
 
-  agent_installer = 'C:/chef/cache/ddagent-cli.msi'
+  agent_installer = "C:/chef/cache/ddagent-cli.#{installer_extension}"
 
   it 'downloads the remote file only if it\'s changed' do
     expect(chef_run).to create_remote_file(agent_installer)
   end
 
-  it 'notifies the removal of the Datadog Agent' do
-    expect(chef_run.remote_file(agent_installer)).to notify('windows_package[Datadog Agent]').to(:remove)
+  it 'doesn\'t remove existing version of the Datadog Agent by default' do
+    expect(chef_run.package('Datadog Agent removal')).to do_nothing
+  end
+
+  it 'notifies the removal of the Datadog Agent when a remote file is downloaded' do
+    expect(chef_run.remote_file(agent_installer)).to notify('package[Datadog Agent removal]').to(:remove)
   end
 
   it 'installs Datadog Agent' do
-    expect(chef_run).to install_windows_package('Datadog Agent')
+    installer_type = installer_extension == :msi ? :msi : :custom
+    expect(chef_run).to install_windows_package('Datadog Agent').with(installer_type: installer_type)
   end
 end