[extension/headerssetter] Change DefaultValue to use configopaque.String type (open-telemetry#39144)

#### Description
Change `DefaultValue` to `opaque.String`  type

#### Link to tracking issue
Fixes
open-telemetry#39127

Signed-off-by: Dani Louca <[email protected]>
Co-authored-by: Antoine Toulme <[email protected]>

Author: 2 people

.chloggen/configopaque-heasersetter.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: extension/headerssetter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Change `DefaultValue` to use `configopaque.String` type.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [39127]
+
+# (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: [user, api]

extension/headerssetterextension/config.go

@@ -5,6 +5,8 @@ package headerssetterextension // import "github.com/open-telemetry/opentelemetr
 
 import (
 	"fmt"
+
+	"go.opentelemetry.io/collector/config/configopaque"
 )
 
 var (
@@ -19,12 +21,12 @@ type Config struct {
 }
 
 type HeaderConfig struct {
-	Action        ActionValue `mapstructure:"action"`
-	Key           *string     `mapstructure:"key"`
-	Value         *string     `mapstructure:"value"`
-	FromContext   *string     `mapstructure:"from_context"`
-	FromAttribute *string     `mapstructure:"from_attribute"`
-	DefaultValue  *string     `mapstructure:"default_value"`
+	Action        ActionValue          `mapstructure:"action"`
+	Key           *string              `mapstructure:"key"`
+	Value         *string              `mapstructure:"value"`
+	FromContext   *string              `mapstructure:"from_context"`
+	FromAttribute *string              `mapstructure:"from_attribute"`
+	DefaultValue  *configopaque.String `mapstructure:"default_value"`
 }
 
 // ActionValue is the enum to capture the four types of actions to perform on a header

extension/headerssetterextension/config_test.go

@@ -42,7 +42,7 @@ func TestLoadConfig(t *testing.T) {
 						Key:          stringp("X-Scope-OrgID"),
 						Action:       INSERT,
 						FromContext:  stringp("tenant_id"),
-						DefaultValue: stringp("some_id"),
+						DefaultValue: opaquep("some_id"),
 						Value:        nil,
 					},
 					{
@@ -163,7 +163,7 @@ func TestValidateConfig(t *testing.T) {
 					Key:          stringp("name"),
 					Action:       INSERT,
 					FromContext:  stringp("from context"),
-					DefaultValue: stringp("default"),
+					DefaultValue: opaquep("default"),
 				},
 			},
 			nil,

extension/headerssetterextension/extension.go

@@ -66,7 +66,7 @@ func newHeadersSetterExtension(cfg *Config, logger *zap.Logger) (*headerSetterEx
 		case header.FromAttribute != nil:
 			defaultValue := ""
 			if header.DefaultValue != nil {
-				defaultValue = *header.DefaultValue
+				defaultValue = string(*header.DefaultValue)
 			}
 			s = &source.AttributeSource{
 				Key:          *header.FromAttribute,
@@ -75,7 +75,7 @@ func newHeadersSetterExtension(cfg *Config, logger *zap.Logger) (*headerSetterEx
 		case header.FromContext != nil:
 			defaultValue := ""
 			if header.DefaultValue != nil {
-				defaultValue = *header.DefaultValue
+				defaultValue = string(*header.DefaultValue)
 			}
 			s = &source.ContextSource{
 				Key:          *header.FromContext,

extension/headerssetterextension/extension_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"go.opentelemetry.io/collector/client"
+	"go.opentelemetry.io/collector/config/configopaque"
 )
 
 type mockRoundTripper struct{}
@@ -225,7 +226,7 @@ var (
 						Key:          &header,
 						Action:       INSERT,
 						FromContext:  stringp("tenant"),
-						DefaultValue: stringp("default_tenant"),
+						DefaultValue: opaquep("default_tenant"),
 					},
 				},
 			},
@@ -243,7 +244,7 @@ var (
 						Key:          &header,
 						Action:       INSERT,
 						FromContext:  stringp("tenant"),
-						DefaultValue: stringp("default_tenant"),
+						DefaultValue: opaquep("default_tenant"),
 					},
 				},
 			},
@@ -260,3 +261,7 @@ var (
 func stringp(str string) *string {
 	return &str
 }
+
+func opaquep(stro configopaque.String) *configopaque.String {
+	return &stro
+}

extension/headerssetterextension/go.mod

@@ -7,6 +7,7 @@ require (
 	go.opentelemetry.io/collector/client v1.29.1-0.20250402200755-cb5c3f4fb9dc
 	go.opentelemetry.io/collector/component v1.29.1-0.20250402200755-cb5c3f4fb9dc
 	go.opentelemetry.io/collector/component/componenttest v0.123.1-0.20250402200755-cb5c3f4fb9dc
+	go.opentelemetry.io/collector/config/configopaque v1.29.1-0.20250402200755-cb5c3f4fb9dc
 	go.opentelemetry.io/collector/confmap v1.29.1-0.20250402200755-cb5c3f4fb9dc
 	go.opentelemetry.io/collector/confmap/xconfmap v0.123.1-0.20250402200755-cb5c3f4fb9dc
 	go.opentelemetry.io/collector/extension v1.29.1-0.20250402200755-cb5c3f4fb9dc