Added recipe for go_expvar metrics collection

recipes/go_expvar.rb

@@ -0,0 +1,24 @@
+include_recipe 'datadog::dd-agent'
+
+# Monitor Go metrics exported via expvar
+#  node['datadog']['go_expvar']['instances'] = [
+#   {
+#     'expvar_url' => 'http://localhost:8080/debug/vars',
+#     'tags' => [
+#        'application:my_go_app'
+#      ],
+#     'metrics' => [
+#       {
+#         'path' => 'test_metrics_name_1', 'alias' => 'go_expvar.test_metrics_name_1', 'type' => 'gauge'
+#       },
+#       {
+#         'path' => 'test_metrics_name_2', 'alias' => 'go_expvar.test_metrics_name_2', 'type' => 'gauge', 'tags' => ['tag1', 'tag2']
+#       }
+#     ]
+#   }
+#  ]
+
+datadog_monitor 'go_expvar' do
+  init_config node['datadog']['go_expvar']['init_config']
+  instances node['datadog']['go_expvar']['instances']
+end

spec/integrations/go_expvar_spec.rb

@@ -0,0 +1,60 @@
+describe 'datadog::go_expvar' do
+  expected_yaml = <<-EOF
+    init_config: {}
+    instances:
+    - expvar_url: http://localhost:8080/debug/vars
+      tags:
+      - application:my_go_app
+      metrics:
+      - path: test_metric_name_1
+        alias: go_expvar.test_metric_name_1
+        type: gauge
+      - path: test_metric_name_2
+        alias: go_expvar.test_metric_name_2
+        type: rate
+        tags:
+        - category:customtag1
+        - customtag2
+  EOF
+
+  cached(:chef_run) do
+    ChefSpec::SoloRunner.new(step_into: ['datadog_monitor']) do |node|
+      node.automatic['languages'] = { 'python' => { 'version' => '2.7.2' } }
+
+      node.set['datadog'] = {
+        'api_key' => 'someapikey',
+        'go_expvar' => {
+          init_config: nil,
+          instances: [
+            {
+              'expvar_url' => 'http://localhost:8080/debug/vars',
+              'tags' => ['application:my_go_app'],
+              'metrics' => [
+                {
+                  'path' => 'test_metric_name_1', 'alias' => 'go_expvar.test_metric_name_1', 'type' => 'gauge'
+                },
+                {
+                  'path' => 'test_metric_name_2', 'alias' => 'go_expvar.test_metric_name_2', 'type' => 'rate', 'tags' => ['category:customtag1', 'customtag2']
+                }
+              ]
+            }
+          ]
+        }
+      }
+    end.converge(described_recipe)
+  end
+
+  subject { chef_run }
+
+  it_behaves_like 'datadog-agent'
+
+  it { is_expected.to include_recipe('datadog::dd-agent') }
+
+  it { is_expected.to add_datadog_monitor('go_expvar') }
+
+  it 'renders expected YAML config file' do
+    expect(chef_run).to render_file('/etc/dd-agent/conf.d/go_expvar.yaml').with_content { |content|
+      expect(YAML.load(content).to_json).to be_json_eql(YAML.load(expected_yaml).to_json)
+    }
+  end
+end

templates/default/go_expvar.yaml.erb

@@ -0,0 +1,3 @@
+# Generated by Chef, local modifications will be overwritten
+
+<%= JSON.parse(({ 'init_config' => @init_config, 'instances' => @instances}).to_json).to_yaml %>