From 72ef99d2115e536822afaf5f04e2fa8c63f91c4e Mon Sep 17 00:00:00 2001
From: nimbold <11913706+nimbold@users.noreply.github.com>
Date: Mon, 8 Jun 2026 05:46:24 +0330
Subject: [PATCH] refactor: add backward compatibility support for extension
 tokens

---
 Sources/Firelink/LocalExtensionServer.swift | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/Sources/Firelink/LocalExtensionServer.swift b/Sources/Firelink/LocalExtensionServer.swift
index 4dec076..5dec809 100644
--- a/Sources/Firelink/LocalExtensionServer.swift
+++ b/Sources/Firelink/LocalExtensionServer.swift
@@ -8,7 +8,15 @@ final class LocalExtensionServer: @unchecked Sendable {
         static let maxRequestBytes = 128 * 1024
         static let maxURLCount = 200
         static let extensionRequestHeader = "x-firelink-extension"
-        static let extensionRequestToken = "firelink-extension-v1"
+        
+        // IMPORTANT(Backward Compatibility):
+        // Extension updates on Mozilla/Chrome stores can take several days to be approved.
+        // Therefore, we MUST NOT introduce breaking changes to the LocalExtensionServer API 
+        // without maintaining backward compatibility for older extensions.
+        // If you need to update the API (e.g., changing the payload structure), add the new 
+        // token here and handle both versions in `processRequest`.
+        static let supportedExtensionTokens = Set(["firelink-extension-v1"])
+        
         static let allowedSchemes = Set(["http", "https", "ftp", "sftp"])
     }
 
@@ -138,7 +146,8 @@ final class LocalExtensionServer: @unchecked Sendable {
             return .methodNotAllowed
         }
 
-        guard request.header(named: Constants.extensionRequestHeader) == Constants.extensionRequestToken else {
+        guard let token = request.header(named: Constants.extensionRequestHeader),
+              Constants.supportedExtensionTokens.contains(token) else {
             return .forbidden
         }