feat: parallel generation of JSON web key set

go.mod

@@ -69,6 +69,7 @@ require (
 	golang.org/x/crypto v0.10.0
 	golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1
 	golang.org/x/oauth2 v0.9.0
+	golang.org/x/sync v0.2.0
 	golang.org/x/tools v0.10.0
 )
 

jwk/handler.go

@@ -7,6 +7,8 @@ import (
 	"encoding/json"
 	"net/http"
 
+	"golang.org/x/sync/errgroup"
+
 	"github.com/ory/x/httprouterx"
 
 	"github.com/gofrs/uuid"
@@ -89,25 +91,34 @@ func (h *Handler) SetRoutes(admin *httprouterx.RouterAdmin, public *httprouterx.
 //	  200: jsonWebKeySet
 //	  default: errorOAuth2
 func (h *Handler) discoverJsonWebKeys(w http.ResponseWriter, r *http.Request) {
-	var jwks jose.JSONWebKeySet
-
-	ctx := r.Context()
-	for _, set := range stringslice.Unique(h.r.Config().WellKnownKeys(ctx)) {
-		keys, err := h.r.KeyManager().GetKeySet(ctx, set)
-		if errors.Is(err, x.ErrNotFound) {
-			h.r.Logger().Warnf("JSON Web Key Set \"%s\" does not exist yet, generating new key pair...", set)
-			keys, err = h.r.KeyManager().GenerateAndPersistKeySet(ctx, set, uuid.Must(uuid.NewV4()).String(), string(jose.RS256), "sig")
-			if err != nil {
-				h.r.Writer().WriteError(w, r, err)
-				return
+	eg, ctx := errgroup.WithContext(r.Context())
+	wellKnownKeys := stringslice.Unique(h.r.Config().WellKnownKeys(ctx))
+	keys := make(chan *jose.JSONWebKeySet, len(wellKnownKeys))
+	for _, set := range wellKnownKeys {
+		set := set
+		eg.Go(func() error {
+			k, err := h.r.KeyManager().GetKeySet(ctx, set)
+			if errors.Is(err, x.ErrNotFound) {
+				h.r.Logger().Warnf("JSON Web Key Set %q does not exist yet, generating new key pair...", set)
+				k, err = h.r.KeyManager().GenerateAndPersistKeySet(ctx, set, uuid.Must(uuid.NewV4()).String(), string(jose.RS256), "sig")
+				if err != nil {
+					return err
+				}
+			} else if err != nil {
+				return err
 			}
-		} else if err != nil {
-			h.r.Writer().WriteError(w, r, err)
-			return
-		}
-
-		keys = ExcludePrivateKeys(keys)
-		jwks.Keys = append(jwks.Keys, keys.Keys...)
+			keys <- ExcludePrivateKeys(k)
+			return nil
+		})
+	}
+	if err := eg.Wait(); err != nil {
+		h.r.Writer().WriteError(w, r, err)
+		return
+	}
+	close(keys)
+	var jwks jose.JSONWebKeySet
+	for k := range keys {
+		jwks.Keys = append(jwks.Keys, k.Keys...)
 	}
 
 	h.r.Writer().Write(w, r, &jwks)