Files
feedkit/processors/normalize/helpers.go

85 lines
1.9 KiB
Go

package normalize
import (
"encoding/json"
"fmt"
"time"
"gitea.maximumdirect.net/ejr/feedkit/event"
)
// PayloadJSONBytes extracts a JSON payload into bytes suitable for json.Unmarshal.
//
// Supported payload shapes:
// - json.RawMessage
// - []byte
// - string
// - map[string]any
func PayloadJSONBytes(e event.Event) ([]byte, error) {
if e.Payload == nil {
return nil, fmt.Errorf("payload is nil")
}
switch v := e.Payload.(type) {
case json.RawMessage:
if len(v) == 0 {
return nil, fmt.Errorf("payload is empty json.RawMessage")
}
return []byte(v), nil
case []byte:
if len(v) == 0 {
return nil, fmt.Errorf("payload is empty []byte")
}
return v, nil
case string:
if v == "" {
return nil, fmt.Errorf("payload is empty string")
}
return []byte(v), nil
case map[string]any:
b, err := json.Marshal(v)
if err != nil {
return nil, fmt.Errorf("marshal map payload: %w", err)
}
return b, nil
default:
return nil, fmt.Errorf("unsupported payload type %T", e.Payload)
}
}
// DecodeJSONPayload extracts the event payload as bytes and unmarshals it into T.
func DecodeJSONPayload[T any](in event.Event) (T, error) {
var zero T
b, err := PayloadJSONBytes(in)
if err != nil {
return zero, fmt.Errorf("extract payload: %w", err)
}
var parsed T
if err := json.Unmarshal(b, &parsed); err != nil {
return zero, fmt.Errorf("decode raw payload: %w", err)
}
return parsed, nil
}
// FinalizeEvent builds the output event envelope by copying the input and applying
// the new schema/payload, plus optional EffectiveAt.
func FinalizeEvent(in event.Event, outSchema string, outPayload any, effectiveAt time.Time) (*event.Event, error) {
out := in
out.Schema = outSchema
out.Payload = outPayload
if !effectiveAt.IsZero() {
t := effectiveAt.UTC()
out.EffectiveAt = &t
}
if err := out.Validate(); err != nil {
return nil, err
}
return &out, nil
}