1 files changed, 24 insertions, 0 deletions
diff --git a/src/discord/verification.ts b/src/discord/verification.ts
new file mode 100644
index 0000000..c60c70e
--- /dev/null
+++ b/src/discord/verification.ts
@@ -0,0 +1,24 @@
+import { verifyKey } from 'discord-interactions';
+import type { Environment, DiscordInteraction } from './interfaces.ts';
+
+export async function verifyDiscordRequest(
+  request: Request,
+  environment: Environment,
+): Promise<{ isValid: boolean; interaction?: DiscordInteraction }> {
+  const signature = request.headers.get('x-signature-ed25519');
+  const timestamp = request.headers.get('x-signature-timestamp');
+  const body = await request.text();
+  const isValidRequest =
+    signature &&
+    timestamp &&
+    (await verifyKey(
+      body,
+      signature,
+      timestamp,
+      environment.DISCORD_PUBLIC_KEY,
+    ));
+
+  if (!isValidRequest) return { isValid: false };
+
+  return { interaction: JSON.parse(body) as DiscordInteraction, isValid: true };
+}