Log error on resource schema conflict

sdk/resource/resource.go

@@ -21,6 +21,7 @@ import (
 
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/internal/global"
 )
 
 // Resource describes an entity about which identifying information
@@ -40,7 +41,7 @@ var (
 	defaultResourceOnce sync.Once
 )
 
-var errMergeConflictSchemaURL = errors.New("cannot merge resource due to conflicting Schema URL")
+var errMergeConflictSchemaURL = errors.New("conflicting Schema URL")
 
 // New returns a Resource combined from the user-provided detectors.
 func New(ctx context.Context, opts ...Option) (*Resource, error) {
@@ -177,7 +178,16 @@ func Merge(a, b *Resource) (*Resource, error) {
 	case a.schemaURL == b.schemaURL:
 		schemaURL = a.schemaURL
 	default:
-		return Empty(), errMergeConflictSchemaURL
+		// Log conflict, but do not return an error. The user is not always
+		// able to handle these errors directly (i.e. resource detectors from
+		// 3rd-party packages). Returning something, and logging information,
+		// here is a better user-story than returning an unrecoverable error.
+		global.Error(
+			errMergeConflictSchemaURL,
+			"the merged resource schema URL is empty",
+			"URL 1", a.schemaURL,
+			"URL 2", b.schemaURL,
+		)
 	}
 
 	// Note: 'b' attributes will overwrite 'a' with last-value-wins in attribute.Key()