Add Azure metadata endpoint support

The Azure metadata endpoint has gone GA. This pulls instance information straight from the source.

Signed-off-by: Tim Smith <tsmith@chef.io>

1 files changed, 53 insertions, 0 deletions

diff --git a/lib/ohai/mixin/azure_metadata.rb b/lib/ohai/mixin/azure_metadata.rb
new file mode 100644
index 00000000..e44c0241
--- /dev/null
+++ b/lib/ohai/mixin/azure_metadata.rb
@@ -0,0 +1,53 @@
+#
+# Author:: Tim Smith (<tsmith@chef.io>)
+# Copyright:: Copyright 2017 Chef Software, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require "net/http"
+
+module Ohai
+  module Mixin
+    module AzureMetadata
+
+      AZURE_METADATA_ADDR = "169.254.169.254" unless defined?(AZURE_METADATA_ADDR)
+      AZURE_METADATA_URL = "/metadata/instance?api-version=2017-04-02" unless defined?(AZURE_METADATA_URL)
+
+      # fetch the meta content with a timeout and the required header
+      def http_get(uri)
+        conn = Net::HTTP.start(AZURE_METADATA_ADDR)
+        conn.read_timeout = 6
+        conn.get(uri, initheader = { "Metadata" => "true" })
+      end
+
+      def fetch_metadata
+        Ohai::Log.debug("Mixin AzureMetadata: Fetching metadata from host #{AZURE_METADATA_ADDR} at #{AZURE_METADATA_URL}")
+        response = http_get(AZURE_METADATA_URL)
+        if response.code == "200"
+          begin
+            data = StringIO.new(response.body)
+            parser = FFI_Yajl::Parser.new
+            parser.parse(data)
+          rescue FFI_Yajl::ParseError
+            Ohai::Log.debug("Mixin AzureMetadata: Metadata response is NOT valid JSON")
+            {}
+          end
+        else
+          Ohai::Log.debug("Mixin AzureMetadata: Received resonse code #{response.code} requesting metadata")
+          {}
+        end
+      end
+    end
+  end
+end