From fa9da61aba9af15eb1e4f7a44f05f9d46534f94b Mon Sep 17 00:00:00 2001
From: Runrioter <runrioter@qq.com>
Date: Thu, 24 Aug 2017 15:39:29 +0800
Subject: [PATCH 1/2] fix example bug and use syntactic sugar

---
 example.js   | 4 ++--
 index.js     | 4 +---
 package.json | 2 +-
 3 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/example.js b/example.js
index abf009d..ea47cce 100644
--- a/example.js
+++ b/example.js
@@ -1,7 +1,7 @@
 
 var session = require('./');
-var koa = require('koa');
-var app = koa();
+var Koa = require('koa');
+var app = new Koa();
 
 app.keys = ['some secret hurr'];
 
diff --git a/index.js b/index.js
index d7978c1..b095060 100644
--- a/index.js
+++ b/index.js
@@ -24,9 +24,7 @@ const _CONTEXT_SESSION = Symbol('context#_contextSession');
 module.exports = function(opts, app) {
   // session(app[, opts])
   if (opts && typeof opts.use === 'function') {
-    const tmp = app;
-    app = opts;
-    opts = tmp;
+    [ app, opts ] = [ opts, app ];
   }
   // app required
   if (!app || typeof app.use !== 'function') {
diff --git a/package.json b/package.json
index c05e259..5091185 100644
--- a/package.json
+++ b/package.json
@@ -39,4 +39,4 @@
     "test-travis": "npm run lint && NODE_ENV=test node ./node_modules/.bin/istanbul cover ./node_modules/.bin/_mocha --report lcovonly -- --require should test/*.test.js",
     "lint": "eslint lib test index.js"
   }
-}
\ No newline at end of file
+}

From b2e7c3ac8683342925ab38f4242279fbd16943a5 Mon Sep 17 00:00:00 2001
From: Runrioter <runrioter@qq.com>
Date: Tue, 19 Sep 2017 18:12:28 +0800
Subject: [PATCH 2/2] feat: make encode/decode support store-based session

#88
---
 index.js            |  9 ---------
 lib/context.js      | 26 ++++++++++++++++++++------
 test/cookie.test.js |  8 ++++----
 3 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/index.js b/index.js
index b095060..62aabce 100644
--- a/index.js
+++ b/index.js
@@ -2,7 +2,6 @@
 
 const debug = require('debug')('koa-session');
 const ContextSession = require('./lib/context');
-const util = require('./lib/util');
 const assert = require('assert');
 const uid = require('uid-safe');
 const is = require('is-type-of');
@@ -70,14 +69,6 @@ function formatOpts(opts) {
 
   debug('session options %j', opts);
 
-  // setup encoding/decoding
-  if (typeof opts.encode !== 'function') {
-    opts.encode = util.encode;
-  }
-  if (typeof opts.decode !== 'function') {
-    opts.decode = util.decode;
-  }
-
   const store = opts.store;
   if (store) {
     assert(is.function(store.get), 'store.get must be function');
diff --git a/lib/context.js b/lib/context.js
index f1dc702..8aed0ae 100644
--- a/lib/context.js
+++ b/lib/context.js
@@ -69,10 +69,20 @@ class ContextSession {
     const ctx = this.ctx;
     const opts = this.opts;
 
-    const externalKey = ctx.cookies.get(opts.key, opts);
-    debug('get external key from cookie %s', externalKey);
+    const cookie = ctx.cookies.get(opts.key, opts);
+    debug('get external key from cookie %s', cookie);
 
-    if (!externalKey) {
+    if (!cookie) {
+      // create a new `externalKey`
+      this.create();
+      return;
+    }
+    let externalKey = cookie;
+    try {
+      if (typeof opts.decode === 'function') {
+        externalKey = opts.decode(externalKey);
+      }
+    } catch (err) {
       // create a new `externalKey`
       this.create();
       return;
@@ -109,7 +119,7 @@ class ContextSession {
     let json;
     debug('parse %s', cookie);
     try {
-      json = opts.decode(cookie);
+      json = typeof opts.decode === 'function' ? opts.decode(cookie) : util.decode(cookie);
     } catch (err) {
       // backwards compatibility:
       // create a new session if parsing fails.
@@ -263,13 +273,17 @@ class ContextSession {
         changed,
         rolling: opts.rolling,
       });
-      this.ctx.cookies.set(key, externalKey, opts);
+      let cookie = externalKey;
+      if (typeof opts.encode === 'function') {
+        cookie = opts.encode(externalKey);
+      }
+      this.ctx.cookies.set(key, cookie, opts);
       return;
     }
 
     // save to cookie
     debug('save %j to cookie', json);
-    json = opts.encode(json);
+    json = typeof opts.encode === 'function' ? opts.encode(json) : util.encode(json);
     debug('save %s', json);
 
     this.ctx.cookies.set(key, json, opts);
diff --git a/test/cookie.test.js b/test/cookie.test.js
index dc15fb9..ddc2462 100644
--- a/test/cookie.test.js
+++ b/test/cookie.test.js
@@ -761,10 +761,10 @@ describe('Koa Session Cookie', () => {
     before(() => {
       app = App({ rolling: true });
 
-      app.use(function* () {
-        console.log(this.path);
-        if (this.path === '/set') this.session = { foo: 'bar' };
-        this.body = this.session;
+      app.use(async function(ctx) {
+        console.log(ctx.path);
+        if (ctx.path === '/set') ctx.session = { foo: 'bar' };
+        ctx.body = ctx.session;
       });
     });