value.go

package converter

import (
	"fmt"

	commonpb "go.temporal.io/api/common/v1"
)

type (
	// EncodedValue is used to encapsulate/extract encoded value from workflow/activity.
	EncodedValue interface {
		// HasValue return whether there is value encoded.
		HasValue() bool
		// Get extract the encoded value into strong typed value pointer.
		//
		// Note, values should not be reused for extraction here because merging on
		// top of existing values may result in unexpected behavior similar to
		// json.Unmarshal.
		Get(valuePtr interface{}) error
	}

	// EncodedValues is used to encapsulate/extract encoded one or more values from workflow/activity.
	EncodedValues interface {
		// HasValues return whether there are values encoded.
		HasValues() bool
		// Get extract the encoded values into strong typed value pointers.
		//
		// Note, values should not be reused for extraction here because merging on
		// top of existing values may result in unexpected behavior similar to
		// json.Unmarshal.
		Get(valuePtr ...interface{}) error
	}

	// RawValue is a representation of an unconverted, raw payload.
	//
	// This type can be used as a parameter or return type in workflows and activities to pass through
	// a raw payload. Encoding/decoding of the payload is still done by the system. A RawValue enabled
	// payload converter is required for this.
	RawValue struct {
		payload *commonpb.Payload
	}
)

// NewRawValue creates a new RawValue instance.
func NewRawValue(payload *commonpb.Payload) RawValue {
	return RawValue{payload: payload}
}

func (v RawValue) Payload() *commonpb.Payload {
	return v.payload
}

func (v RawValue) MarshalJSON() ([]byte, error) {
	return nil, fmt.Errorf("RawValue is not JSON serializable")
}

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
}