Merge pull request #1083 from chef/ec2_hypervisor

Detect new Amazon hypervisor used by the C5 instances

4 files changed, 72 insertions, 22 deletions

diff --git a/.travis.yml b/.travis.yml
index dd49c7c8..4acca285 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,7 +10,6 @@ branches:
     - 8-stable
 
 before_install:
-  - gem update --system
   - gem --version
   - rvm @global do gem uninstall bundler -a -x -I || true
   - gem install bundler
diff --git a/appveyor.yml b/appveyor.yml
index bf6cd845..7728c8ad 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -7,6 +7,7 @@ platform:
 environment:
   matrix:
     - ruby_version: "23"
+    - ruby_version: "24"  
 
 clone_folder: c:\projects\ohai
 clone_depth: 1
@@ -19,7 +20,6 @@ install:
   - SET PATH=C:\Ruby%ruby_version%\bin;%PATH%
   - echo %PATH%
   - ruby --version
-  - gem update --system
   - gem --version
   - gem uninstall bundler -a -x -I
   - gem install bundler --quiet --no-ri --no-rdoc
diff --git a/lib/ohai/plugins/ec2.rb b/lib/ohai/plugins/ec2.rb
index 1a3598d8..fdf0084a 100644
--- a/lib/ohai/plugins/ec2.rb
+++ b/lib/ohai/plugins/ec2.rb
@@ -21,7 +21,8 @@
 # How we detect EC2 from easiest to hardest & least reliable
 # 1. Ohai ec2 hint exists. This always works
 # 2. Xen hypervisor UUID starts with 'ec2'. This catches Linux HVM & paravirt instances
-# 3. DMI data mentions amazon. This catches HVM instances in a VPC
+# 3. DMI bios version data mentions amazon. This catches HVM instances in a VPC on the Xen based hypervisor
+# 3. DMI bios vendor data mentions amazon. This catches HVM instances in a VPC on the non-Xen based hypervisor
 # 4. Kernel data mentioned Amazon. This catches Windows HVM & paravirt instances
 
 Ohai.plugin(:EC2) do
@@ -33,32 +34,43 @@ Ohai.plugin(:EC2) do
   include Ohai::Mixin::HttpHelper
 
   provides "ec2"
-  depends "dmi"
 
-  # look for amazon string in dmi bios data
+  # look for amazon string in dmi vendor bios data within the sys tree.
+  # this works even if the system lacks dmidecode use by the Dmi plugin
+  # this gets us detection of new Xen-less HVM instances that are within a VPC
+  # @return [Boolean] do we have Amazon DMI data?
+  def has_ec2_amazon_dmi?
+    # detect a version of '4.2.amazon'
+    if file_val_if_exists("/sys/class/dmi/id/bios_vendor") =~ /Amazon/
+      Ohai::Log.debug("Plugin EC2: has_ec2_amazon_dmi? == true")
+      true
+    else
+      Ohai::Log.debug("Plugin EC2: has_ec2_amazon_dmi? == false")
+      false
+    end
+  end
+
+  # look for amazon string in dmi bios version data within the sys tree.
+  # this works even if the system lacks dmidecode use by the Dmi plugin
   # this gets us detection of HVM instances that are within a VPC
   # @return [Boolean] do we have Amazon DMI data?
-  def has_ec2_dmi?
+  def has_ec2_xen_dmi?
     # detect a version of '4.2.amazon'
-    if get_attribute(:dmi, :bios, :all_records, 0, :Version) =~ /amazon/
-      Ohai::Log.debug("Plugin EC2: has_ec2_dmi? == true")
+    if file_val_if_exists("/sys/class/dmi/id/bios_version") =~ /amazon/
+      Ohai::Log.debug("Plugin EC2: has_ec2_xen_dmi? == true")
       true
     else
-      Ohai::Log.debug("Plugin EC2: has_ec2_dmi? == false")
+      Ohai::Log.debug("Plugin EC2: has_ec2_xen_dmi? == false")
       false
     end
   end
 
-  # looks for a xen UUID that starts with ec2
-  # uses the sys tree on Linux and a WMI query on windows
-  # this gets us detection of HVM and Paravirt hosts
+  # looks for a xen UUID that starts with ec2 from within the Linux sys tree
   # @return [Boolean] do we have a Xen UUID or not?
   def has_ec2_xen_uuid?
-    if ::File.exist?("/sys/hypervisor/uuid")
-      if ::File.read("/sys/hypervisor/uuid") =~ /^ec2/
-        Ohai::Log.debug("Plugin EC2: has_ec2_xen_uuid? == true")
-        return true
-      end
+    if file_val_if_exists("/sys/hypervisor/uuid") =~ /^ec2/
+      Ohai::Log.debug("Plugin EC2: has_ec2_xen_uuid? == true")
+      return true
     end
     Ohai::Log.debug("Plugin EC2: has_ec2_xen_uuid? == false")
     false
@@ -82,13 +94,22 @@ Ohai.plugin(:EC2) do
     end
   end
 
+  # return the contents of a file if the file exists
+  # @param path[String] abs path to the file
+  # @return [String] contents of the file if it exists
+  def file_val_if_exists(path)
+    if ::File.exist?(path)
+      ::File.read(path)
+    end
+  end
+
   # a single check that combines all the various detection methods for EC2
   # @return [Boolean] Does the system appear to be on EC2
   def looks_like_ec2?
     return true if hint?("ec2")
 
     # Even if it looks like EC2 try to connect first
-    if has_ec2_xen_uuid? || has_ec2_dmi? || has_ec2_identifying_number?
+    if has_ec2_xen_uuid? || has_ec2_amazon_dmi? || has_ec2_xen_dmi? || has_ec2_identifying_number?
       return true if can_socket_connect?(Ohai::Mixin::Ec2Metadata::EC2_METADATA_ADDR, 80)
     end
   end
diff --git a/spec/unit/plugins/ec2_spec.rb b/spec/unit/plugins/ec2_spec.rb
index bf64da2b..00937a3a 100644
--- a/spec/unit/plugins/ec2_spec.rb
+++ b/spec/unit/plugins/ec2_spec.rb
@@ -28,6 +28,8 @@ describe Ohai::System, "plugin ec2" do
   before(:each) do
     allow(plugin).to receive(:hint?).with("ec2").and_return(false)
     allow(File).to receive(:exist?).with("/sys/hypervisor/uuid").and_return(false)
+    allow(File).to receive(:exist?).with("/sys/class/dmi/id/bios_vendor").and_return(false)
+    allow(File).to receive(:exist?).with("/sys/class/dmi/id/bios_version").and_return(false)
   end
 
   shared_examples_for "!ec2" do
@@ -332,11 +334,39 @@ describe Ohai::System, "plugin ec2" do
     end
   end # shared examples for ec2
 
-  describe "with ec2 dmi data" do
+  describe "with amazon dmi bios version data" do
     it_behaves_like "ec2"
 
     before(:each) do
-      plugin[:dmi] = { :bios => { :all_records => [ { :Version => "4.2.amazon" } ] } }
+      allow(File).to receive(:exist?).with("/sys/class/dmi/id/bios_version").and_return(true)
+      allow(File).to receive(:read).with("/sys/class/dmi/id/bios_version").and_return("4.2.amazon\n")
+    end
+  end
+
+  describe "with non-amazon dmi bios version data" do
+    it_behaves_like "!ec2"
+
+    before(:each) do
+      allow(File).to receive(:exist?).with("/sys/class/dmi/id/bios_version").and_return(true)
+      allow(File).to receive(:read).with("/sys/class/dmi/id/bios_version").and_return("1.0\n")
+    end
+  end
+
+  describe "with amazon dmi bios vendor data" do
+    it_behaves_like "ec2"
+
+    before(:each) do
+      allow(File).to receive(:exist?).with("/sys/class/dmi/id/bios_vendor").and_return(true)
+      allow(File).to receive(:read).with("/sys/class/dmi/id/bios_vendor").and_return("Amazon EC2\n")
+    end
+  end
+
+  describe "with non-amazon dmi bios vendor data" do
+    it_behaves_like "!ec2"
+
+    before(:each) do
+      allow(File).to receive(:exist?).with("/sys/class/dmi/id/bios_vendor").and_return(true)
+      allow(File).to receive(:read).with("/sys/class/dmi/id/bios_vendor").and_return("Xen\n")
     end
   end
 
@@ -345,7 +375,7 @@ describe Ohai::System, "plugin ec2" do
 
     before(:each) do
       allow(File).to receive(:exist?).with("/sys/hypervisor/uuid").and_return(true)
-      allow(File).to receive(:read).with("/sys/hypervisor/uuid").and_return("ec2a0561-e4d6-8e15-d9c8-2e0e03adcde8")
+      allow(File).to receive(:read).with("/sys/hypervisor/uuid").and_return("ec2a0561-e4d6-8e15-d9c8-2e0e03adcde8\n")
     end
   end
 
@@ -354,7 +384,7 @@ describe Ohai::System, "plugin ec2" do
 
     before(:each) do
       allow(File).to receive(:exist?).with("/sys/hypervisor/uuid").and_return(true)
-      allow(File).to receive(:read).with("/sys/hypervisor/uuid").and_return("123a0561-e4d6-8e15-d9c8-2e0e03adcde8")
+      allow(File).to receive(:read).with("/sys/hypervisor/uuid").and_return("123a0561-e4d6-8e15-d9c8-2e0e03adcde8\n")
     end
   end