Function TestServiceSampling

internal/telemetry/telemetry_test.go:432–487

(t *testing.T)

}

func TestServiceSampling(t *testing.T) {
	tests := []struct {
		name         string
		sampleRate   int
		sampleBucket byte
		wantPayloads int
	}{
		{
			name:         "sampleRate 0 sends all events",
			sampleRate:   0,
			sampleBucket: 99,
			wantPayloads: 1,
		},
		{
			name:         "sampleRate 100 sends all events regardless of bucket",
			sampleRate:   100,
			sampleBucket: 99,
			wantPayloads: 1,
		},
		{
			name:         "bucket below sampleRate sends events",
			sampleRate:   50,
			sampleBucket: 49,
			wantPayloads: 1,
		},
		{
			name:         "bucket at sampleRate drops events",
			sampleRate:   50,
			sampleBucket: 50,
			wantPayloads: 0,
		},
		{
			name:         "bucket above sampleRate drops events",
			sampleRate:   1,
			sampleBucket: 50,
			wantPayloads: 0,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			// Given a configured sample rate and a deterministic sampling bucket
			t.Cleanup(stubDeviceID("test-device"))
			var payloads []SendTelemetryPayload
			svc := NewService(func(p SendTelemetryPayload) { payloads = append(payloads, p) }, WithSampleRate(tt.sampleRate))
			// Fix the random bucket so sampling boundaries can be asserted through delivery.
			svc.(*service).sampleBucket = tt.sampleBucket
			svc.Record(ghtelemetry.Event{Type: "test"})

			// When the invocation finishes
			svc.Finish()

			// Then the sampling policy determines whether a payload is delivered
			assert.Len(t, payloads, tt.wantPayloads)
		})
	}
}

func TestServiceReducingSampleRateExcludesInvocation(t *testing.T) {