test(processors.converter): Add unit-test for tracking metrics (#14740)

plugins/processors/converter/converter_test.go

@@ -2,12 +2,14 @@ package converter
 
 import (
 	"math"
+	"sync"
 	"testing"
 	"time"
 
 	"github.com/stretchr/testify/require"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/metric"
 	"github.com/influxdata/telegraf/testutil"
 )
 
@@ -667,14 +669,13 @@ func TestConverter(t *testing.T) {
 			},
 		},
 	}
+
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			tt.converter.Log = testutil.Logger{}
+			require.NoError(t, tt.converter.Init())
 
-			err := tt.converter.Init()
-			require.NoError(t, err)
 			actual := tt.converter.Apply(tt.input)
-
 			testutil.RequireMetricsEqual(t, tt.expected, actual)
 		})
 	}
@@ -773,11 +774,9 @@ func TestMeasurement(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			tt.converter.Log = testutil.Logger{}
-			err := tt.converter.Init()
-			require.NoError(t, err)
+			require.NoError(t, tt.converter.Init())
 
 			actual := tt.converter.Apply(tt.input)
-
 			testutil.RequireMetricsEqual(t, tt.expected, actual)
 		})
 	}
@@ -787,6 +786,56 @@ func TestEmptyConfigInitError(t *testing.T) {
 	converter := &Converter{
 		Log: testutil.Logger{},
 	}
-	err := converter.Init()
-	require.Error(t, err)
+	require.Error(t, converter.Init())
+}
+
+func TestTracking(t *testing.T) {
+	inputRaw := []telegraf.Metric{
+		metric.New("foo", map[string]string{}, map[string]interface{}{"value": 42, "topic": "telegraf"}, time.Unix(0, 0)),
+		metric.New("bar", map[string]string{}, map[string]interface{}{"value": 42, "topic": "telegraf"}, time.Unix(0, 0)),
+		metric.New("baz", map[string]string{}, map[string]interface{}{"value": 42, "topic": "telegraf"}, time.Unix(0, 0)),
+	}
+
+	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)
+	}
+
+	input := make([]telegraf.Metric, 0, len(inputRaw))
+	for _, m := range inputRaw {
+		tm, _ := metric.WithTracking(m, notify)
+		input = append(input, tm)
+	}
+
+	expected := []telegraf.Metric{
+		metric.New("telegraf", map[string]string{}, map[string]interface{}{"value": 42}, time.Unix(0, 0)),
+		metric.New("telegraf", map[string]string{}, map[string]interface{}{"value": 42}, time.Unix(0, 0)),
+		metric.New("telegraf", map[string]string{}, map[string]interface{}{"value": 42}, time.Unix(0, 0)),
+	}
+
+	plugin := &Converter{
+		Fields: &Conversion{
+			Measurement: []string{"topic"},
+		},
+	}
+	require.NoError(t, plugin.Init())
+
+	// Process expected metrics and compare with resulting metrics
+	actual := plugin.Apply(input...)
+	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(expected) == len(delivered)
+	}, time.Second, 100*time.Millisecond, "%d delivered but %d expected", len(delivered), len(expected))
 }