refactor: IP address handling in ipaddrPlugin

Author: winverse

packages/velog-server/src/common/plugins/global/ipaddrPlugin.ts

@@ -4,8 +4,12 @@ const ipaddrPlugin: FastifyPluginAsync = async (fastify) => {
   fastify.decorateRequest('ipaddr', null)
   fastify.addHook('preHandler', (request, reply, done) => {
     const fromCdnIp = request.headers['gcdn-client-ip']
+    const xForwardedIp = request.headers['X-Forwarded-For']
+
     const graphCdnAddress = Array.isArray(fromCdnIp) ? fromCdnIp[0] : fromCdnIp
-    const ipaddr = graphCdnAddress || request.ips?.slice(-1)[0] || request.ip
+    const xForwardedForAdress = Array.isArray(xForwardedIp) ? xForwardedIp[0] : xForwardedIp
+
+    const ipaddr = xForwardedForAdress ?? graphCdnAddress ?? request.ips?.slice(-1)[0] ?? request.ip
     request.ipaddr = ipaddr
     done()
   })