Expose raw Failure and Payload protos on SDK error and result types

converter/value.go

@@ -57,3 +57,22 @@ func (v RawValue) MarshalJSON() ([]byte, error) {
 func (v *RawValue) UnmarshalJSON(b []byte) error {
 	return fmt.Errorf("RawValue is not JSON serializable")
 }
+
+// ValuesPayloads is an optional interface that EncodedValue and EncodedValues may implement
+// to expose the underlying commonpb.Payloads without decoding.
+type ValuesPayloads interface {
+	// Payloads gets the underlying commonpb.Payloads
+	Payloads() *commonpb.Payloads
+}
+
+// GetPayloads acts as a helper to extract the raw *commonpb.Payloads from an EncodedValue
+// or EncodedValues, if the underlying implementation supports it via the ValuesPayloads interface.
+// If the underlying implementation does not support it, this returns nil.
+//
+// Exposed as: [go.temporal.io/sdk/converter.GetPayloads]
+func GetPayloads(encoded interface{}) *commonpb.Payloads {
+	if vp, ok := encoded.(ValuesPayloads); ok {
+		return vp.Payloads()
+	}
+	return nil
+}

internal/error.go

@@ -566,6 +566,10 @@ func (e *temporalError) failure() *failurepb.Failure {
 	return e.originalFailure
 }
 
+func (e *temporalError) Failure() *failurepb.Failure {
+	return e.originalFailure
+}
+
 // IsCanceledError returns whether error in CanceledError.
 func IsCanceledError(err error) bool {
 	var canceledErr *CanceledError

internal/workflow.go

@@ -2132,6 +2132,11 @@ func (b EncodedValue) HasValue() bool {
 	return b.value != nil
 }
 
+// Payloads gets the underlying commonpb.Payloads
+func (b EncodedValue) Payloads() *commonpb.Payloads {
+	return b.value
+}
+
 // SideEffect executes the provided function once, records its result into the workflow history. The recorded result on
 // history will be returned without executing the provided function during replay. This guarantees the deterministic
 // requirement for workflow as the exact same result will be returned in replay.

internal/workflow_testsuite.go

@@ -98,11 +98,16 @@ func (b EncodedValues) Get(valuePtr ...interface{}) error {
 	return b.dataConverter.FromPayloads(b.values, valuePtr...)
 }
 
-// HasValues return whether there are values
+// HasValues return whether there are values encoded.
 func (b EncodedValues) HasValues() bool {
 	return b.values != nil
 }
 
+// Payloads gets the underlying commonpb.Payloads
+func (b EncodedValues) Payloads() *commonpb.Payloads {
+	return b.values
+}
+
 // Get extract data from encoded data to desired value type. valuePtr is pointer to the actual value type.
 func (b ErrorDetailsValues) Get(valuePtr ...interface{}) error {
 	if !b.HasValues() {
@@ -117,11 +122,16 @@ func (b ErrorDetailsValues) Get(valuePtr ...interface{}) error {
 	return nil
 }
 
-// HasValues return whether there are values.
+// HasValues return whether there are values encoded.
 func (b ErrorDetailsValues) HasValues() bool {
 	return len(b) != 0
 }
 
+// Payloads gets the underlying commonpb.Payloads
+func (b ErrorDetailsValues) Payloads() *commonpb.Payloads {
+	return nil
+}
+
 // NewTestWorkflowEnvironment creates a new instance of TestWorkflowEnvironment. Use the returned TestWorkflowEnvironment
 // to run your workflow in the test environment.
 func (s *WorkflowTestSuite) NewTestWorkflowEnvironment() *TestWorkflowEnvironment {