fix: prevent failure of collected data

pkg/collector/collector.go

@@ -16,7 +16,7 @@ import (
 	"github.com/traefik/traefik/v2/pkg/version"
 )
 
-// collectorURL URL where the stats are send.
+// collectorURL URL where the stats are sent.
 const collectorURL = "https://collect.traefik.io/9vxmmkcdmalbdi635d4jgc5p5rx0h7h8"
 
 // Collected data.
@@ -30,16 +30,30 @@ type data struct {
 
 // Collect anonymous data.
 func Collect(staticConfiguration *static.Configuration) error {
-	anonConfig, err := redactor.Anonymize(staticConfiguration)
+	buf, err := createBody(staticConfiguration)
 	if err != nil {
 		return err
 	}
 
+	resp, err := makeHTTPClient().Post(collectorURL, "application/json; charset=utf-8", buf)
+	if resp != nil {
+		_ = resp.Body.Close()
+	}
+
+	return err
+}
+
+func createBody(staticConfiguration *static.Configuration) (*bytes.Buffer, error) {
+	anonConfig, err := redactor.Anonymize(staticConfiguration)
+	if err != nil {
+		return nil, err
+	}
+
 	log.WithoutContext().Infof("Anonymous stats sent to %s: %s", collectorURL, anonConfig)
 
 	hashConf, err := hashstructure.Hash(staticConfiguration, nil)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	data := &data{
@@ -53,15 +67,10 @@ func Collect(staticConfiguration *static.Configuration) error {
 	buf := new(bytes.Buffer)
 	err = json.NewEncoder(buf).Encode(data)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
-	resp, err := makeHTTPClient().Post(collectorURL, "application/json; charset=utf-8", buf)
-	if resp != nil {
-		resp.Body.Close()
-	}
-
-	return err
+	return buf, err
 }
 
 func makeHTTPClient() *http.Client {

pkg/collector/collector_test.go

@@ -0,0 +1,21 @@
+package collector
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"github.com/traefik/traefik/v2/pkg/config/static"
+)
+
+func Test_createBody(t *testing.T) {
+	var staticConfiguration static.Configuration
+
+	err := hydrate(&staticConfiguration)
+	require.NoError(t, err)
+
+	buffer, err := createBody(&staticConfiguration)
+	require.NoError(t, err)
+
+	assert.NotEmpty(t, buffer)
+}

pkg/collector/hydration_test.go

@@ -0,0 +1,166 @@
+package collector
+
+import (
+	"fmt"
+	"reflect"
+	"time"
+
+	"github.com/traefik/paerser/types"
+)
+
+const (
+	sliceItemNumber     = 2
+	mapItemNumber       = 2
+	defaultString       = "foobar"
+	defaultNumber       = 42
+	defaultBool         = true
+	defaultMapKeyPrefix = "name"
+)
+
+func hydrate(element interface{}) error {
+	field := reflect.ValueOf(element)
+	return fill(field)
+}
+
+func fill(field reflect.Value) error {
+	switch field.Kind() {
+	case reflect.Struct:
+		if err := setStruct(field); err != nil {
+			return err
+		}
+	case reflect.Ptr:
+		if err := setPointer(field); err != nil {
+			return err
+		}
+	case reflect.Slice:
+		if err := setSlice(field); err != nil {
+			return err
+		}
+	case reflect.Map:
+		if err := setMap(field); err != nil {
+			return err
+		}
+	case reflect.Interface:
+		if err := fill(field.Elem()); err != nil {
+			return err
+		}
+	case reflect.String:
+		setTyped(field, defaultString)
+	case reflect.Int:
+		setTyped(field, defaultNumber)
+	case reflect.Int8:
+		setTyped(field, int8(defaultNumber))
+	case reflect.Int16:
+		setTyped(field, int16(defaultNumber))
+	case reflect.Int32:
+		setTyped(field, int32(defaultNumber))
+	case reflect.Int64:
+		switch field.Type() {
+		case reflect.TypeOf(types.Duration(time.Second)):
+			setTyped(field, int64(defaultNumber*int(time.Second)))
+		default:
+			setTyped(field, int64(defaultNumber))
+		}
+	case reflect.Uint:
+		setTyped(field, uint(defaultNumber))
+	case reflect.Uint8:
+		setTyped(field, uint8(defaultNumber))
+	case reflect.Uint16:
+		setTyped(field, uint16(defaultNumber))
+	case reflect.Uint32:
+		setTyped(field, uint32(defaultNumber))
+	case reflect.Uint64:
+		setTyped(field, uint64(defaultNumber))
+	case reflect.Bool:
+		setTyped(field, defaultBool)
+	case reflect.Float32:
+		setTyped(field, float32(defaultNumber))
+	case reflect.Float64:
+		setTyped(field, float64(defaultNumber))
+	}
+
+	return nil
+}
+
+func setTyped(field reflect.Value, i interface{}) {
+	baseValue := reflect.ValueOf(i)
+	if field.Kind().String() == field.Type().String() {
+		field.Set(baseValue)
+	} else {
+		field.Set(baseValue.Convert(field.Type()))
+	}
+}
+
+func setMap(field reflect.Value) error {
+	field.Set(reflect.MakeMap(field.Type()))
+
+	for i := 0; i < mapItemNumber; i++ {
+		baseKeyName := makeKeyName(field.Type().Elem())
+		key := reflect.ValueOf(fmt.Sprintf("%s%d", baseKeyName, i))
+
+		// generate value
+		ptrType := reflect.PtrTo(field.Type().Elem())
+		ptrValue := reflect.New(ptrType)
+		if err := fill(ptrValue); err != nil {
+			return err
+		}
+		value := ptrValue.Elem().Elem()
+
+		field.SetMapIndex(key, value)
+	}
+	return nil
+}
+
+func makeKeyName(typ reflect.Type) string {
+	switch typ.Kind() {
+	case reflect.Ptr:
+		return typ.Elem().Name()
+	case reflect.String,
+		reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+		reflect.Bool, reflect.Float32, reflect.Float64:
+		return defaultMapKeyPrefix
+	default:
+		return typ.Name()
+	}
+}
+
+func setStruct(field reflect.Value) error {
+	for i := 0; i < field.NumField(); i++ {
+		fld := field.Field(i)
+		stFld := field.Type().Field(i)
+
+		if !stFld.IsExported() || fld.Kind() == reflect.Func {
+			continue
+		}
+
+		if err := fill(fld); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func setSlice(field reflect.Value) error {
+	field.Set(reflect.MakeSlice(field.Type(), sliceItemNumber, sliceItemNumber))
+	for j := 0; j < field.Len(); j++ {
+		if err := fill(field.Index(j)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func setPointer(field reflect.Value) error {
+	if field.IsNil() {
+		field.Set(reflect.New(field.Type().Elem()))
+		if err := fill(field.Elem()); err != nil {
+			return err
+		}
+	} else {
+		if err := fill(field.Elem()); err != nil {
+			return err
+		}
+	}
+	return nil
+}