WIP

Author: Watson1978

Gemfile

@@ -9,7 +9,9 @@ gem "grpc", "~> 1.73"
 gem "grpc-tools"
 gem "irb"
 gem "rake", "~> 13.0"
-gem "test-unit", "~> 3.0"
+gem "rr"
+gem "test-unit"
+gem "test-unit-rr"
 gem "timecop"
 
 gem "rubocop", "~> 1.75"

test/fluent/plugin/test_in_opentelemetry_metrics.rb

@@ -3,25 +3,125 @@
 require "helper"
 
 require "fluent/plugin/in_opentelemetry_metrics"
+require "fluent/plugin/opentelemetry/constant"
 require "fluent/plugin/opentelemetry/request"
 require "fluent/test/driver/input"
 
-class Fluent::Plugin::OpentelemetryMetricsInputTest < Test::Unit::TestCase
+require "test_plugin_classes"
 
+class Fluent::Plugin::OpentelemetryMetricsInputTest < Test::Unit::TestCase
   def setup
     Fluent::Test.setup
+
+    # Enable mock_process_clock for freezing Fluent::EventTime
+    Timecop.mock_process_clock = true
+    Timecop.freeze(Time.parse("2025-01-01 00:00:00 UTC"))
+    @event_time = Fluent::EventTime.now
   end
-  
+
+  setup do
+    # check @type and type in one configuration
+    conf = <<~CONFIG
+      <source>
+        @type test_in_gen
+        @id test_in_gen
+        num 10
+      </source>
+      <filter>
+        @type test_filter
+        @id test_filter
+      </filter>
+      <match **>
+        @type relabel
+        @id test_relabel
+        @label @test
+      </match>
+      <label @test>
+        <match **>
+          @type test_out
+          @id test_out
+        </match>
+      </label>
+      <label @copy>
+        <match **>
+          @type copy
+          <store>
+            @type test_out
+            @id copy_out_1
+          </store>
+          <store>
+            @type test_out
+            @id copy_out_2
+          </store>
+        </match>
+      </label>
+      <label @ERROR>
+        <match>
+          @type null
+          @id null
+        </match>
+      </label>
+    CONFIG
+
+    @root_agent = Fluent::RootAgent.new(log: $log) # rubocop:disable Style/GlobalVars
+    stub(Fluent::Engine).root_agent { @root_agent }
+    @root_agent = configure_root_agent(@root_agent, conf)
+  end
+
+  def teardown
+    Timecop.mock_process_clock = false
+    Timecop.return
+  end
+
+  def create_driver(conf = config)
+    Fluent::Test::Driver::Input.new(Fluent::Plugin::OpentelemetryMetricsInput).configure(conf)
+  end
+
+  def configure_root_agent(root_agent, conf_str)
+    conf = Fluent::Config.parse(conf_str, "(test)", "(test_dir)", true)
+    root_agent.configure(conf)
+    root_agent
+  end
+
+  def config
+    <<~CONFIG
+      tag opentelemetry.test
+      emit_interval 1s
+    CONFIG
+  end
+
   def test_metrics_record_conforms_to_spec
     metrics = Fluent::Plugin::OpentelemetryMetricsInput::Metrics.new(metric_name_prefix: "fluentd_")
 
-    assert_false metrics.values.empty?
-
     # validate the metrics record
     assert_nothing_raised do
       # If record does not conform to OpenTelemetry Protocol, it raises Google::Protobuf::ParseError.
       # To validate strictly, it set ignore_unknown_fields to false.
       Fluent::Plugin::Opentelemetry::Request::Metrics.new(metrics.record, ignore_unknown_fields: false)
     end
   end
+
+  def test_emit_metrics
+    d = create_driver
+    d.run(expect_records: 1)
+
+    event = d.events.first
+    assert_equal("opentelemetry.test", event[0])
+    assert_equal(@event_time, event[1])
+    assert_equal(Fluent::Plugin::Opentelemetry::RECORD_TYPE_METRICS, event[2]["type"])
+    assert_nothing_raised do
+      JSON.parse(event[2]["message"])
+    end
+  end
+
+  def test_metrics_name_prefix
+    d = create_driver(config + "metric_name_prefix foobarbaz_")
+    d.run(expect_records: 1)
+
+    event = d.events.first
+    record = JSON.parse(event[2]["message"])
+
+    metrics = record["resourceMetrics"][0]["scopeMetrics"][0]["metrics"]
+    assert_true(metrics.all? { |metric| metric["name"].start_with?("foobarbaz_") })
+  end
 end

test/helper.rb

@@ -14,6 +14,9 @@
 require "timecop"
 require "zlib"
 
+require "rr"
+require "test/unit/rr"
+
 include Fluent::Test::Helpers
 
 module TestData