[component] Change component.Type underlying type to a struct (#9472)

**Description:** 

Follow up to #9414 and
open-telemetry/opentelemetry-collector-contrib/pull/31038.

**Link to tracking Issue:** Fixes #9208.

.chloggen/mx-psi_switch-to-type.yaml

@@ -0,0 +1,25 @@
+# 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. otlpreceiver)
+component: component
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Change underlying type of `component.Type` to an opaque struct.
+
+# One or more tracking issues or pull requests related to the change
+issues: [9208]
+
+# (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:
+
+# 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: [api]

component/config.go

@@ -110,11 +110,13 @@ func callValidateIfPossible(v reflect.Value) error {
 }
 
 // Type is the component type as it is used in the config.
-type Type string
+type Type struct {
+	name string
+}
 
 // String returns the string representation of the type.
 func (t Type) String() string {
-	return string(t)
+	return t.name
 }
 
 // typeRegexp is used to validate the type of a component.
@@ -130,12 +132,12 @@ var typeRegexp = regexp.MustCompile(`^[a-zA-Z][0-9a-zA-Z_]*$`)
 // - can only contain ASCII alphanumeric characters and '_'.
 func NewType(ty string) (Type, error) {
 	if len(ty) == 0 {
-		return Type(""), fmt.Errorf("id must not be empty")
+		return Type{}, fmt.Errorf("id must not be empty")
 	}
 	if !typeRegexp.MatchString(ty) {
-		return Type(""), fmt.Errorf("invalid character(s) in type %q", ty)
+		return Type{}, fmt.Errorf("invalid character(s) in type %q", ty)
 	}
-	return Type(ty), nil
+	return Type{name: ty}, nil
 }
 
 // MustNewType creates a type. It panics if the type is invalid.
@@ -155,14 +157,18 @@ func MustNewType(strType string) Type {
 // collecting metrics, traces and logs, this can expand in the future.
 type DataType = Type
 
+func mustNewDataType(strType string) DataType {
+	return MustNewType(strType)
+}
+
 // Currently supported data types. Add new data types here when new types are supported in the future.
-const (
+var (
 	// DataTypeTraces is the data type tag for traces.
-	DataTypeTraces DataType = "traces"
+	DataTypeTraces = mustNewDataType("traces")
 
 	// DataTypeMetrics is the data type tag for metrics.
-	DataTypeMetrics DataType = "metrics"
+	DataTypeMetrics = mustNewDataType("metrics")
 
 	// DataTypeLogs is the data type tag for logs.
-	DataTypeLogs DataType = "logs"
+	DataTypeLogs = mustNewDataType("logs")
 )

component/config_test.go

@@ -13,7 +13,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-var _ fmt.Stringer = (Type)("")
+var _ fmt.Stringer = Type{}
 
 type configChildStruct struct {
 	Child    errConfig

config/confighttp/confighttp_test.go

@@ -423,7 +423,7 @@ func TestHTTPClientSettingWithAuthConfig(t *testing.T) {
 			name: "with_auth_configuration_has_extension_and_compression",
 			settings: ClientConfig{
 				Endpoint:    "localhost:1234",
-				Auth:        &configauth.Authentication{AuthenticatorID: component.NewID("mock")},
+				Auth:        &configauth.Authentication{AuthenticatorID: component.MustNewID("mock")},
 				Compression: configcompression.TypeGzip,
 			},
 			shouldErr: false,