feat(processor/regex): Add ability to check every tag for regex repla…

…ce (#10927)

plugins/processors/regex/README.md

@@ -15,7 +15,7 @@ For metrics transforms, `key` denotes the element that should be transformed. Fu
 
   # Tag and field conversions defined in a separate sub-tables
   [[processors.regex.tags]]
-    ## Tag to change
+    ## Tag to change, "*" will change every tag
     key = "resp_code"
     ## Regular expression to match on a tag value
     pattern = "^(\\d)\\d\\d$"

plugins/processors/regex/regex.go

@@ -97,14 +97,17 @@ func (r *Regex) Init() error {
 func (r *Regex) Apply(in ...telegraf.Metric) []telegraf.Metric {
 	for _, metric := range in {
 		for _, converter := range r.Tags {
-			if value, ok := metric.GetTag(converter.Key); ok {
-				if key, newValue := r.convert(converter, value); newValue != "" {
-					if converter.Append {
-						if v, ok := metric.GetTag(key); ok {
-							newValue = v + newValue
-						}
+			if converter.Key == "*" {
+				for _, tag := range metric.TagList() {
+					regex := r.regexCache[converter.Pattern]
+					if regex.MatchString(tag.Value) {
+						newValue := regex.ReplaceAllString(tag.Value, converter.Replacement)
+						updateTag(converter, metric, tag.Key, newValue)
 					}
-					metric.AddTag(key, newValue)
+				}
+			} else if value, ok := metric.GetTag(converter.Key); ok {
+				if key, newValue := r.convert(converter, value); newValue != "" {
+					updateTag(converter, metric, key, newValue)
 				}
 			}
 		}
@@ -212,6 +215,15 @@ func (r *Regex) convert(c converter, src string) (key string, value string) {
 	return c.Key, value
 }
 
+func updateTag(converter converter, metric telegraf.Metric, key string, newValue string) {
+	if converter.Append {
+		if v, ok := metric.GetTag(key); ok {
+			newValue = v + newValue
+		}
+	}
+	metric.AddTag(key, newValue)
+}
+
 func init() {
 	processors.Add("regex", func() telegraf.Processor { return &Regex{} })
 }

plugins/processors/regex/regex_test.go

@@ -1,6 +1,8 @@
 package regex
 
 import (
+	"github.com/influxdata/telegraf/metric"
+	"github.com/stretchr/testify/assert"
 	"testing"
 	"time"
 
@@ -40,6 +42,21 @@ func newM2() telegraf.Metric {
 	)
 }
 
+func newUUIDTags() telegraf.Metric {
+	m1 := metric.New("access_log",
+		map[string]string{
+			"compound": "other-18cb0b46-73b8-4084-9fc4-5105f32a8a68",
+			"simple":   "d60be57c-2f43-4e4f-a68a-4ca8204bae41",
+			"control":  "not_uuid",
+		},
+		map[string]interface{}{
+			"request": "/users/42/",
+		},
+		time.Now(),
+	)
+	return m1
+}
+
 func TestFieldConversions(t *testing.T) {
 	tests := []struct {
 		message        string
@@ -828,3 +845,43 @@ func BenchmarkConversions(b *testing.B) {
 		_ = processed
 	}
 }
+
+func TestAnyTagConversion(t *testing.T) {
+	tests := []struct {
+		message      string
+		converter    converter
+		expectedTags map[string]string
+	}{
+		{
+			message: "Should change existing tag",
+			converter: converter{
+				Key:         "*",
+				Pattern:     "[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}",
+				Replacement: "{UUID}",
+			},
+			expectedTags: map[string]string{
+				"compound": "other-{UUID}",
+				"simple":   "{UUID}",
+				"control":  "not_uuid",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		regex := Regex{
+			Tags: []converter{test.converter},
+			Log:  testutil.Logger{},
+		}
+		require.NoError(t, regex.Init())
+
+		processed := regex.Apply(newUUIDTags())
+
+		expectedFields := map[string]interface{}{
+			"request": "/users/42/",
+		}
+
+		assert.Equal(t, expectedFields, processed[0].Fields(), test.message, "Should not change fields")
+		assert.Equal(t, test.expectedTags, processed[0].Tags(), test.message)
+		assert.Equal(t, "access_log", processed[0].Name(), "Should not change name")
+	}
+}