Improve JWTAuthenticator validation of Issuer,Discovery

internal/controller/utilserr.go

@@ -0,0 +1,21 @@
+// Copyright 2024 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package controller
+
+import (
+	"fmt"
+	"strings"
+)
+
+func TruncateMostLongErr(err error) string {
+	const max = 300
+	msg := err.Error()
+
+	// always log oidc and x509 errors completely
+	if len(msg) <= max || strings.Contains(msg, "oidc:") || strings.Contains(msg, "x509:") {
+		return msg
+	}
+
+	return msg[:max] + fmt.Sprintf(" [truncated %d chars]", len(msg)-max)
+}