diff --git a/server/web3service/controllers/jwt.js b/server/web3service/controllers/jwt.js
index 6783773..f419503 100644
--- a/server/web3service/controllers/jwt.js
+++ b/server/web3service/controllers/jwt.js
@@ -3,6 +3,42 @@ const base64url = require('base64url');
 const jwksClient = require('jwks-rsa');
 const jwt = require('jsonwebtoken');
 
+const jwksKeyHash = {};
+
+function asyncVerify(jwksUri, data) {
+  return new Promise((resolve) => {
+    const ret = {
+      err: null,
+      decoded: null
+    };
+    const client = jwksClient({
+      jwksUri: jwksUri
+    });
+    function getKey(header, cb ) {
+      console.log(header);
+      client.getSigningKey(header.kid, function(err, key) {
+        console.log(err);
+        console.log(key);
+        const signingKey = key.publicKey || key.rsaPublicKey;
+        if (!err) {
+          jwksKeyHash[jwksUri] = {
+            'key': key,
+            'last_refresh_time': 0
+          };
+        }
+        cb(null, signingKey);
+      });
+    };
+    jwt.verify(data, getKey, function(err, decoded) {
+      console.log(err);
+      console.log(decoded);
+      ret.err = err;
+      ret.decoded = decoded;
+      resolve(ret);
+    });
+  });
+}
+
 async function verify(session) {
   const postData = session.getBody();
   console.log(postData);
@@ -11,21 +47,14 @@ async function verify(session) {
   const header = base64url.decode(arr[0]);
   const payload = base64url.decode(arr[1]);
   const sign = base64url.decode(arr[2]);
-  const client = jwksClient({
-    jwksUri: jwksUri
-  });
-  function getKey(header, cb ) {
-    console.log(header);
-    client.getSigningKey(header.kid, function(err, key) {
-      console.log(err);
-      console.log(key);
-      const signingKey = key.publicKey || key.rsaPublicKey;
-      cb(null, signingKey);
-    });
-  };
-  jwt.verify(postData['data'], getKey, function(err, decoded) {
-    console.log(err);
-    console.log(decoded);
+  const {err, decoded} = await asyncVerify(jwksUri, postData['data']);
+  console.log(err, decoded);
+  if (err != null) {
+    session.rspErr(500, err);
+    return;
+  }
+  session.rspData({
+    'decoded': decoded
   });
 }