[processor/k8sattributes] move k8sattr.fieldExtractConfigRegex.disallow feature gate to stable (#37615)

<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description

move k8sattr.fieldExtractConfigRegex.disallow feature gate to stable
which was hiding the `FieldExtractConfig.Regex` parameter and was
deprecated. According to the standards, it can be now moved to `stable`.

<!-- Issue number (e.g. #1234) or full URL to issue, if applicable. -->
#### Link to tracking issue
Fixes #25128

---------

Signed-off-by: odubajDT <[email protected]>

Author: odubajDT

.chloggen/regex-deprecation.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: breaking
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: processor/k8sattributes
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Move k8sattr.fieldExtractConfigRegex.disallow feature gate to stable"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [25128]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

processor/k8sattributesprocessor/README.md

@@ -233,21 +233,18 @@ extract:
     - tag_name: a1 # extracts value of annotation from pods with key `annotation-one` and inserts it as a tag with key `a1`
       key: annotation-one
       from: pod
-    - tag_name: a2 # extracts value of annotation from namespaces with key `annotation-two` with regexp and inserts it as a tag with key `a2`
+    - tag_name: a2 # extracts value of annotation from namespaces with key `annotation-two` and inserts it as a tag with key `a2`
       key: annotation-two
-      regex: field=(?P<value>.+)
       from: namespace
-    - tag_name: a3 # extracts value of annotation from nodes with key `annotation-three` with regexp and inserts it as a tag with key `a3`
+    - tag_name: a3 # extracts value of annotation from nodes with key `annotation-three` and inserts it as a tag with key `a3`
       key: annotation-three
-      regex: field=(?P<value>.+)
       from: node
   labels:
     - tag_name: l1 # extracts value of label from namespaces with key `label1` and inserts it as a tag with key `l1`
       key: label1
       from: namespace
-    - tag_name: l2 # extracts value of label from pods with key `label2` with regexp and inserts it as a tag with key `l2`
+    - tag_name: l2 # extracts value of label from pods with key `label2` and inserts it as a tag with key `l2`
       key: label2
-      regex: field=(?P<value>.+)
       from: pod
     - tag_name: l3 # extracts value of label from nodes with key `label3` and inserts it as a tag with key `l3`
       key: label3
@@ -480,23 +477,7 @@ timestamp value as an RFC3339 compliant timestamp.
 ### `k8sattr.fieldExtractConfigRegex.disallow`
 
 The `k8sattr.fieldExtractConfigRegex.disallow` [feature gate](https://github.com/open-telemetry/opentelemetry-collector/blob/main/featuregate/README.md#collector-feature-gates) disallows the usage of the `extract.annotations.regex` and `extract.labels.regex` fields.
-The validation performed on the configuration will fail, if at least one of the parameters is set (non-empty) and `k8sattr.fieldExtractConfigRegex.disallow` is set to `true` (default `false`).
-
-#### Example Usage
-
-The following config with the feature gate set will lead to validation error:
-
-`config.yaml`:
-
-  ```yaml
-  extract:
-    labels:
-      regex: <my-regex1>
-    annotations:
-      regex: <my-regex2>
-  ```
-
-  Run collector: `./otelcol --config config.yaml --feature-gates=k8sattr.fieldExtractConfigRegex.disallow`
+The feature gate is in `stable` stage, which means it can no longer be disabled and is therefore enabled by default.
 
 #### Migration
 

processor/k8sattributesprocessor/config.go

@@ -15,11 +15,13 @@ import (
 	"github.com/open-telemetry/opentelemetry-collector-contrib/processor/k8sattributesprocessor/internal/kube"
 )
 
+//nolint:unused
 var disallowFieldExtractConfigRegex = featuregate.GlobalRegistry().MustRegister(
 	"k8sattr.fieldExtractConfigRegex.disallow",
-	featuregate.StageBeta,
+	featuregate.StageStable,
 	featuregate.WithRegisterDescription("When enabled, usage of the FieldExtractConfig.Regex field is disallowed"),
 	featuregate.WithRegisterFromVersion("v0.106.0"),
+	featuregate.WithRegisterToVersion("v0.122.0"),
 )
 
 // Config defines configuration for k8s attributes processor.
@@ -77,20 +79,6 @@ func (cfg *Config) Validate() error {
 			return fmt.Errorf("%s is not a valid choice for From. Must be one of: pod, namespace, node", f.From)
 		}
 
-		if f.Regex != "" {
-			if disallowFieldExtractConfigRegex.IsEnabled() {
-				return fmt.Errorf("the extract.annotations.regex and extract.labels.regex fields have been deprecated, please use the `ExtractPatterns` function in the transform processor instead")
-			}
-			r, err := regexp.Compile(f.Regex)
-			if err != nil {
-				return err
-			}
-			names := r.SubexpNames()
-			if len(names) != 2 || names[1] != "value" {
-				return fmt.Errorf("regex must contain exactly one named submatch (value)")
-			}
-		}
-
 		if f.KeyRegex != "" {
 			_, err := regexp.Compile("^(?:" + f.KeyRegex + ")$")
 			if err != nil {
@@ -212,29 +200,6 @@ type FieldExtractConfig struct {
 	// Out of Key or KeyRegex, only one option is expected to be configured at a time.
 	KeyRegex string `mapstructure:"key_regex"`
 
-	// Regex is an optional field used to extract a sub-string from a complex field value.
-	// The supplied regular expression must contain one named parameter with the string "value"
-	// as the name. For example, if your pod spec contains the following annotation,
-	//
-	// kubernetes.io/change-cause: 2019-08-28T18:34:33Z APP_NAME=my-app GIT_SHA=58a1e39 CI_BUILD=4120
-	//
-	// and you'd like to extract the GIT_SHA and the CI_BUILD values as tags, then you must
-	// specify the following two extraction rules:
-	//
-	// extract:
-	//   annotations:
-	//     - tag_name: git.sha
-	//       key: kubernetes.io/change-cause
-	//       regex: GIT_SHA=(?P<value>\w+)
-	//     - tag_name: ci.build
-	//       key: kubernetes.io/change-cause
-	//       regex: JENKINS=(?P<value>[\w]+)
-	//
-	// this will add the `git.sha` and `ci.build` resource attributes.
-	// Deprecated: [v0.106.0] Use the `ExtractPatterns` function in the transform processor instead.
-	// More information about how to replace the regex field can be found in the k8sattributes processor readme.
-	Regex string `mapstructure:"regex"`
-
 	// From represents the source of the labels/annotations.
 	// Allowed values are "pod", "namespace", and "node". The default is pod.
 	From string `mapstructure:"from"`

processor/k8sattributesprocessor/config_test.go

@@ -13,7 +13,6 @@ import (
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/confmap/confmaptest"
 	"go.opentelemetry.io/collector/confmap/xconfmap"
-	"go.opentelemetry.io/collector/featuregate"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/k8sconfig"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/processor/k8sattributesprocessor/internal/kube"
@@ -24,9 +23,8 @@ func TestLoadConfig(t *testing.T) {
 	t.Parallel()
 
 	tests := []struct {
-		id            component.ID
-		expected      component.Config
-		disallowRegex bool
+		id       component.ID
+		expected component.Config
 	}{
 		{
 			id: component.NewID(metadata.Type),
@@ -48,11 +46,11 @@ func TestLoadConfig(t *testing.T) {
 					Metadata: []string{"k8s.pod.name", "k8s.pod.uid", "k8s.pod.ip", "k8s.deployment.name", "k8s.namespace.name", "k8s.node.name", "k8s.pod.start_time", "k8s.cluster.uid"},
 					Annotations: []FieldExtractConfig{
 						{TagName: "a1", Key: "annotation-one", From: "pod"},
-						{TagName: "a2", Key: "annotation-two", Regex: "field=(?P<value>.+)", From: kube.MetadataFromPod},
+						{TagName: "a2", Key: "annotation-two", From: kube.MetadataFromPod},
 					},
 					Labels: []FieldExtractConfig{
 						{TagName: "l1", Key: "label1", From: "pod"},
-						{TagName: "l2", Key: "label2", Regex: "field=(?P<value>.+)", From: kube.MetadataFromPod},
+						{TagName: "l2", Key: "label2", From: kube.MetadataFromPod},
 					},
 				},
 				Filter: FilterConfig{
@@ -110,7 +108,6 @@ func TestLoadConfig(t *testing.T) {
 				},
 				WaitForMetadataTimeout: 10 * time.Second,
 			},
-			disallowRegex: false,
 		},
 		{
 			id: component.NewIDWithName(metadata.Type, "3"),
@@ -135,37 +132,9 @@ func TestLoadConfig(t *testing.T) {
 				WaitForMetadataTimeout: 10 * time.Second,
 			},
 		},
-		{
-			id: component.NewIDWithName(metadata.Type, "deprecated-regex"),
-			expected: &Config{
-				APIConfig:   k8sconfig.APIConfig{AuthType: k8sconfig.AuthTypeKubeConfig},
-				Passthrough: false,
-				Extract: ExtractConfig{
-					Metadata: enabledAttributes(),
-					Annotations: []FieldExtractConfig{
-						{Regex: "field=(?P<value>.+)", From: "pod"},
-					},
-					Labels: []FieldExtractConfig{
-						{Regex: "field=(?P<value>.+)", From: "pod"},
-					},
-				},
-				Exclude: ExcludeConfig{
-					Pods: []ExcludePodConfig{
-						{Name: "jaeger-agent"},
-						{Name: "jaeger-collector"},
-					},
-				},
-				WaitForMetadataTimeout: 10 * time.Second,
-			},
-			disallowRegex: false,
-		},
 		{
 			id: component.NewIDWithName(metadata.Type, "too_many_sources"),
 		},
-		{
-			id:            component.NewIDWithName(metadata.Type, "deprecated-regex"),
-			disallowRegex: true,
-		},
 		{
 			id: component.NewIDWithName(metadata.Type, "bad_keys_labels"),
 		},
@@ -178,30 +147,12 @@ func TestLoadConfig(t *testing.T) {
 		{
 			id: component.NewIDWithName(metadata.Type, "bad_from_annotations"),
 		},
-		{
-			id: component.NewIDWithName(metadata.Type, "bad_regex_labels"),
-		},
-		{
-			id: component.NewIDWithName(metadata.Type, "bad_regex_annotations"),
-		},
 		{
 			id: component.NewIDWithName(metadata.Type, "bad_keyregex_labels"),
 		},
 		{
 			id: component.NewIDWithName(metadata.Type, "bad_keyregex_annotations"),
 		},
-		{
-			id: component.NewIDWithName(metadata.Type, "bad_regex_groups_labels"),
-		},
-		{
-			id: component.NewIDWithName(metadata.Type, "bad_regex_groups_annotations"),
-		},
-		{
-			id: component.NewIDWithName(metadata.Type, "bad_regex_name_labels"),
-		},
-		{
-			id: component.NewIDWithName(metadata.Type, "bad_regex_name_annotations"),
-		},
 		{
 			id: component.NewIDWithName(metadata.Type, "bad_filter_label_op"),
 		},
@@ -212,12 +163,6 @@ func TestLoadConfig(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.id.String(), func(t *testing.T) {
-			if !tt.disallowRegex {
-				require.NoError(t, featuregate.GlobalRegistry().Set(disallowFieldExtractConfigRegex.ID(), false))
-				t.Cleanup(func() {
-					require.NoError(t, featuregate.GlobalRegistry().Set(disallowFieldExtractConfigRegex.ID(), true))
-				})
-			}
 			cm, err := confmaptest.LoadConf(filepath.Join("testdata", "config.yaml"))
 			require.NoError(t, err)
 

processor/k8sattributesprocessor/options.go

@@ -236,15 +236,6 @@ func extractFieldRules(fieldType string, fields ...FieldExtractConfig) ([]kube.F
 			name = fmt.Sprintf("k8s.%v.%v.%v", a.From, fieldType, a.Key)
 		}
 
-		var r *regexp.Regexp
-		if a.Regex != "" {
-			var err error
-			r, err = regexp.Compile(a.Regex)
-			if err != nil {
-				return rules, err
-			}
-		}
-
 		var keyRegex *regexp.Regexp
 		var hasKeyRegexReference bool
 		if a.KeyRegex != "" {
@@ -260,7 +251,7 @@ func extractFieldRules(fieldType string, fields ...FieldExtractConfig) ([]kube.F
 		}
 
 		rules = append(rules, kube.FieldExtractionRule{
-			Name: name, Key: a.Key, KeyRegex: keyRegex, HasKeyRegexReference: hasKeyRegexReference, Regex: r, From: a.From,
+			Name: name, Key: a.Key, KeyRegex: keyRegex, HasKeyRegexReference: hasKeyRegexReference, From: a.From,
 		})
 	}
 	return rules, nil

processor/k8sattributesprocessor/options_test.go

@@ -89,16 +89,14 @@ func TestWithExtractAnnotations(t *testing.T) {
 				{
 					TagName: "tag1",
 					Key:     "key1",
-					Regex:   "field=(?P<value>.+)",
 					From:    kube.MetadataFromPod,
 				},
 			},
 			[]kube.FieldExtractionRule{
 				{
-					Name:  "tag1",
-					Key:   "key1",
-					Regex: regexp.MustCompile(`field=(?P<value>.+)`),
-					From:  kube.MetadataFromPod,
+					Name: "tag1",
+					Key:  "key1",
+					From: kube.MetadataFromPod,
 				},
 			},
 			"",
@@ -228,16 +226,14 @@ func TestWithExtractLabels(t *testing.T) {
 				{
 					TagName: "tag1",
 					Key:     "key1",
-					Regex:   "field=(?P<value>.+)",
 					From:    kube.MetadataFromPod,
 				},
 			},
 			[]kube.FieldExtractionRule{
 				{
-					Name:  "tag1",
-					Key:   "key1",
-					Regex: regexp.MustCompile(`field=(?P<value>.+)`),
-					From:  kube.MetadataFromPod,
+					Name: "tag1",
+					Key:  "key1",
+					From: kube.MetadataFromPod,
 				},
 			},
 			"",
@@ -610,18 +606,6 @@ func Test_extractFieldRules(t *testing.T) {
 				},
 			},
 		},
-		{
-			name: "badregex",
-			args: args{"field", []FieldExtractConfig{
-				{
-					TagName: "name",
-					Key:     "key",
-					Regex:   "[",
-					From:    kube.MetadataFromPod,
-				},
-			}},
-			wantErr: true,
-		},
 		{
 			name: "keyregex-capture-group",
 			args: args{"labels", []FieldExtractConfig{