chore: Parallel attestors per type.

Signed-off-by: Matthias Glastra <[email protected]>

attestation/context.go

@@ -19,6 +19,7 @@ import (
 	"crypto"
 	"fmt"
 	"os"
+	"sync"
 	"time"
 
 	"github.com/in-toto/go-witness/cryptoutil"
@@ -138,16 +139,27 @@ func (ctx *AttestationContext) RunAttestors() error {
 	order := runTypeOrder()
 	for _, k := range order {
 		log.Debugf("Starting %s attestors...", k.String())
+
+		var wg sync.WaitGroup
+		ch := make(chan int, len(attestors))
+
 		for _, att := range attestors[k] {
-			log.Infof("Starting %v attestor...", att.Name())
-			ctx.runAttestor(att)
+			wg.Add(1)
+			go func(att Attestor) {
+				defer func() { wg.Done(); <-ch }()
+				ctx.runAttestor(att)
+			}(att)
 		}
+		wg.Wait()
+		log.Infof("Completed %s attestors...", k.String())
 	}
 
 	return nil
 }
 
 func (ctx *AttestationContext) runAttestor(attestor Attestor) {
+	log.Infof("Starting %v attestor...", attestor.Name())
+
 	startTime := time.Now()
 	if err := attestor.Attest(ctx); err != nil {
 		ctx.completedAttestors = append(ctx.completedAttestors, CompletedAttestor{
@@ -171,6 +183,8 @@ func (ctx *AttestationContext) runAttestor(attestor Attestor) {
 	if producer, ok := attestor.(Producer); ok {
 		ctx.addProducts(producer)
 	}
+
+	log.Debugf("Finished %v attestor...", attestor.Name())
 }
 
 func (ctx *AttestationContext) CompletedAttestors() []CompletedAttestor {