Add isoBase64URL.trimPadding()

1 files changed, 9 insertions, 1 deletions

diff --git a/packages/server/src/helpers/iso/isoBase64URL.ts b/packages/server/src/helpers/iso/isoBase64URL.ts
index 68ed896..99bf82a 100644
--- a/packages/server/src/helpers/iso/isoBase64URL.ts
+++ b/packages/server/src/helpers/iso/isoBase64URL.ts
@@ -1,4 +1,5 @@
 import { base64 } from '../../deps.ts';
+import type { Base64URLString } from '../../deps.ts';
 
 /**
  * Decode from a Base64URL-encoded string to an ArrayBuffer. Best used when converting a
@@ -65,6 +66,13 @@ export function isBase64(input: string): boolean {
  */
 export function isBase64URL(input: string): boolean {
   // Trim padding characters from the string if present
-  input = input.replace(/=/g, '');
+  input = trimPadding(input);
   return base64.validate(input, true);
 }
+
+/**
+ * Remove optional padding from a base64url-encoded string
+ */
+export function trimPadding(input: Base64URLString): Base64URLString {
+  return input.replace(/=/g, '');
+}