feat(cli): add json output to attestation push (#730)

Signed-off-by: Miguel Martinez Trivino <[email protected]>

Author: migmartri

app/cli/cmd/attestation_push.go

@@ -82,10 +82,16 @@ func newAttestationPushCmd() *cobra.Command {
 				return newGracefulError(err)
 			}
 
-			if err := encodeJSON(res.Envelope); err != nil {
-				return err
+			// NOTE: we are not moving yet to full table by default
+			// to maintain backward compatibility
+			if flagOutputFormat == formatJSON {
+				return encodeJSON(res)
 			}
 
+			// default to mix of json and text to stdout and stderr by default
+			// kept to maintain backward compatibility
+			// TODO: in the future we'll render either a table or a proper report
+			fmt.Println(res.Envelope)
 			if res.Digest != "" {
 				logger.Info().Msgf("Attestation Digest: %s", res.Digest)
 			}

app/cli/internal/action/attestation_push.go

@@ -16,6 +16,7 @@
 package action
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -35,8 +36,8 @@ type AttestationPushOpts struct {
 }
 
 type AttestationResult struct {
-	Digest   string         `json:"digest"`
-	Envelope *dsse.Envelope `json:"envelope"`
+	Digest   string `json:"digest"`
+	Envelope string `json:"envelope"`
 }
 
 type AttestationPush struct {
@@ -129,7 +130,14 @@ func (action *AttestationPush) Run(ctx context.Context, attestationID string, ru
 		return nil, err
 	}
 
-	attestationResult := &AttestationResult{Envelope: envelope}
+	var rawEnvelope bytes.Buffer
+	encoder := json.NewEncoder(&rawEnvelope)
+	encoder.SetIndent("", "   ")
+	if err := encoder.Encode(envelope); err != nil {
+		return nil, fmt.Errorf("failed to encode output: %w", err)
+	}
+
+	attestationResult := &AttestationResult{Envelope: rawEnvelope.String()}
 
 	action.Logger.Debug().Msg("render completed")
 	if action.c.CraftingState.DryRun {