test(processors.aws_ec2): Add unit-test for tracking metrics (#14788)

plugins/processors/aws_ec2/ec2_test.go

@@ -1,12 +1,17 @@
 package aws_ec2
 
 import (
+	"sync"
 	"testing"
 	"time"
 
+	"github.com/coocood/freecache"
 	"github.com/stretchr/testify/require"
 
+	"github.com/influxdata/telegraf"
 	"github.com/influxdata/telegraf/config"
+	"github.com/influxdata/telegraf/metric"
+	"github.com/influxdata/telegraf/plugins/common/parallel"
 	"github.com/influxdata/telegraf/testutil"
 )
 
@@ -72,3 +77,110 @@ func TestBasicInitInvalidTagsReturnAnError(t *testing.T) {
 	err := p.Init()
 	require.Error(t, err)
 }
+
+func TestTracking(t *testing.T) {
+	// Setup raw input and expected output
+	inputRaw := []telegraf.Metric{
+		metric.New(
+			"m1",
+			map[string]string{
+				"metric_tag": "from_metric",
+			},
+			map[string]interface{}{"value": int64(1)},
+			time.Unix(0, 0),
+		),
+		metric.New(
+			"m2",
+			map[string]string{
+				"metric_tag": "foo_metric",
+			},
+			map[string]interface{}{"value": int64(2)},
+			time.Unix(0, 0),
+		),
+	}
+	expected := []telegraf.Metric{
+		metric.New(
+			"m1",
+			map[string]string{
+				"metric_tag": "from_metric",
+				"accountId":  "123456789",
+				"instanceId": "i-123456789123",
+			},
+			map[string]interface{}{"value": int64(1)},
+			time.Unix(0, 0),
+		),
+		metric.New(
+			"m2",
+			map[string]string{
+				"metric_tag": "foo_metric",
+				"accountId":  "123456789",
+				"instanceId": "i-123456789123",
+			},
+			map[string]interface{}{"value": int64(2)},
+			time.Unix(0, 0),
+		),
+	}
+
+	// Create fake notification for testing
+	var mu sync.Mutex
+	delivered := make([]telegraf.DeliveryInfo, 0, len(inputRaw))
+	notify := func(di telegraf.DeliveryInfo) {
+		mu.Lock()
+		defer mu.Unlock()
+		delivered = append(delivered, di)
+	}
+
+	// Convert raw input to tracking metric
+	input := make([]telegraf.Metric, 0, len(inputRaw))
+	for _, m := range inputRaw {
+		tm, _ := metric.WithTracking(m, notify)
+		input = append(input, tm)
+	}
+
+	// Prepare and start the plugin
+	plugin := &AwsEc2Processor{
+		MaxParallelCalls: DefaultMaxParallelCalls,
+		TagCacheSize:     DefaultCacheSize,
+		Timeout:          config.Duration(DefaultTimeout),
+		CacheTTL:         config.Duration(DefaultCacheTTL),
+		ImdsTags:         []string{"accountId", "instanceId"},
+		Log:              &testutil.Logger{},
+		imdsTagsMap:      make(map[string]struct{}),
+	}
+	require.NoError(t, plugin.Init())
+
+	// Instead of starting the plugin which tries to connect to the remote
+	// service, we just fill the cache and start the minimum mechanics to
+	// process the metrics.
+	plugin.tagCache = freecache.NewCache(DefaultCacheSize)
+	require.NoError(t, plugin.tagCache.Set([]byte("accountId"), []byte("123456789"), -1))
+	require.NoError(t, plugin.tagCache.Set([]byte("instanceId"), []byte("i-123456789123"), -1))
+
+	var acc testutil.Accumulator
+	plugin.parallel = parallel.NewOrdered(&acc, plugin.asyncAdd, plugin.TagCacheSize, plugin.MaxParallelCalls)
+
+	// Schedule the metrics and wait until they are ready to perform the
+	// comparison
+	for _, in := range input {
+		require.NoError(t, plugin.Add(in, &acc))
+	}
+
+	require.Eventually(t, func() bool {
+		return int(acc.NMetrics()) >= len(expected)
+	}, 3*time.Second, 100*time.Millisecond)
+
+	actual := acc.GetTelegrafMetrics()
+	testutil.RequireMetricsEqual(t, expected, actual)
+
+	// Simulate output acknowledging delivery
+	for _, m := range actual {
+		m.Accept()
+	}
+
+	// Check delivery
+	require.Eventuallyf(t, func() bool {
+		mu.Lock()
+		defer mu.Unlock()
+		return len(input) == len(delivered)
+	}, time.Second, 100*time.Millisecond, "%d delivered but %d expected", len(delivered), len(expected))
+}