Refactor collectors

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

pkg/collector/textfile/textfile_test.go

@@ -0,0 +1,154 @@
+package textfile
+
+import (
+	"io"
+	"strings"
+	"testing"
+
+	"github.com/dimchansky/utfbom"
+	dto "github.com/prometheus/client_model/go"
+)
+
+func TestCRFilter(t *testing.T) {
+	sr := strings.NewReader("line 1\r\nline 2")
+	cr := carriageReturnFilteringReader{r: sr}
+	b, err := io.ReadAll(cr)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if string(b) != "line 1\nline 2" {
+		t.Errorf("Unexpected output %q", b)
+	}
+}
+
+func TestCheckBOM(t *testing.T) {
+	testdata := []struct {
+		encoding utfbom.Encoding
+		err      string
+	}{
+		{utfbom.Unknown, ""},
+		{utfbom.UTF8, ""},
+		{utfbom.UTF16BigEndian, "UTF16BigEndian"},
+		{utfbom.UTF16LittleEndian, "UTF16LittleEndian"},
+		{utfbom.UTF32BigEndian, "UTF32BigEndian"},
+		{utfbom.UTF32LittleEndian, "UTF32LittleEndian"},
+	}
+	for _, d := range testdata {
+		err := checkBOM(d.encoding)
+		if d.err == "" && err != nil {
+			t.Error(err)
+		}
+		if d.err != "" && err == nil {
+			t.Errorf("Missing expected error %s", d.err)
+		}
+		if err != nil && !strings.Contains(err.Error(), d.err) {
+			t.Error(err)
+		}
+	}
+}
+
+func TestDuplicateMetricEntry(t *testing.T) {
+	metric_name := "windows_sometest"
+	metric_help := "This is a Test."
+	metric_type := dto.MetricType_GAUGE
+
+	gauge_value := 1.0
+
+	gauge := dto.Gauge{
+		Value: &gauge_value,
+	}
+
+	label1_name := "display_name"
+	label1_value := "foobar"
+
+	label1 := dto.LabelPair{
+		Name:  &label1_name,
+		Value: &label1_value,
+	}
+
+	label2_name := "display_version"
+	label2_value := "13.4.0"
+
+	label2 := dto.LabelPair{
+		Name:  &label2_name,
+		Value: &label2_value,
+	}
+
+	metric1 := dto.Metric{
+		Label: []*dto.LabelPair{&label1, &label2},
+		Gauge: &gauge,
+	}
+
+	metric2 := dto.Metric{
+		Label: []*dto.LabelPair{&label1, &label2},
+		Gauge: &gauge,
+	}
+
+	duplicate := dto.MetricFamily{
+		Name:   &metric_name,
+		Help:   &metric_help,
+		Type:   &metric_type,
+		Metric: []*dto.Metric{&metric1, &metric2},
+	}
+
+	duplicateFamily := []*dto.MetricFamily{}
+	duplicateFamily = append(duplicateFamily, &duplicate)
+
+	// Ensure detection for duplicate metrics
+	if !duplicateMetricEntry(duplicateFamily) {
+		t.Errorf("Duplicate not found in duplicateFamily")
+	}
+
+	label3_name := "test"
+	label3_value := "1.0"
+
+	label3 := dto.LabelPair{
+		Name:  &label3_name,
+		Value: &label3_value,
+	}
+	metric3 := dto.Metric{
+		Label: []*dto.LabelPair{&label1, &label2, &label3},
+		Gauge: &gauge,
+	}
+
+	differentLabels := dto.MetricFamily{
+		Name:   &metric_name,
+		Help:   &metric_help,
+		Type:   &metric_type,
+		Metric: []*dto.Metric{&metric1, &metric3},
+	}
+
+	duplicateFamily = []*dto.MetricFamily{}
+	duplicateFamily = append(duplicateFamily, &differentLabels)
+
+	// Additional label on second metric should not be cause for duplicate detection
+	if duplicateMetricEntry(duplicateFamily) {
+		t.Errorf("Unexpected duplicate found in differentLabels")
+	}
+
+	label4_value := "2.0"
+
+	label4 := dto.LabelPair{
+		Name:  &label3_name,
+		Value: &label4_value,
+	}
+	metric4 := dto.Metric{
+		Label: []*dto.LabelPair{&label1, &label2, &label4},
+		Gauge: &gauge,
+	}
+
+	differentValues := dto.MetricFamily{
+		Name:   &metric_name,
+		Help:   &metric_help,
+		Type:   &metric_type,
+		Metric: []*dto.Metric{&metric3, &metric4},
+	}
+	duplicateFamily = []*dto.MetricFamily{}
+	duplicateFamily = append(duplicateFamily, &differentValues)
+
+	// Additional label with different values metric should not be cause for duplicate detection
+	if duplicateMetricEntry(duplicateFamily) {
+		t.Errorf("Unexpected duplicate found in differentValues")
+	}
+}