Fix token middleware crash

Fix token middleware to check if `req.loopbackContext` is active.
The context is not active for example when express-session calls
setImmediate which breaks CLS.

Author: azatoth

package.json

@@ -63,6 +63,7 @@
     "cookie-parser": "^1.3.4",
     "es5-shim": "^4.1.0",
     "eslint-config-loopback": "^1.0.0",
+    "express-session": "^1.14.0",
     "grunt": "^1.0.1",
     "grunt-browserify": "^5.0.0",
     "grunt-cli": "^1.2.0",

server/middleware/token.js

@@ -125,7 +125,7 @@ function token(options) {
       req.accessToken = token || null;
       rewriteUserLiteral(req, currentUserLiteral);
       var ctx = req.loopbackContext;
-      if (ctx) ctx.set('accessToken', token);
+      if (ctx && ctx.active) ctx.set('accessToken', token);
       next(err);
     });
   };

test/access-token.test.js

@@ -8,6 +8,8 @@ var LoopBackContext = require('loopback-context');
 var contextMiddleware = require('loopback-context').perRequest;
 var loopback = require('../');
 var extend = require('util')._extend;
+var session = require('express-session');
+
 var Token = loopback.AccessToken.extend('MyToken');
 var ds = loopback.createDataSource({ connector: loopback.Memory });
 Token.attachTo(ds);
@@ -509,6 +511,30 @@ describe('app.enableAuth()', function() {
         done();
       });
   });
+
+  // See https://github.com/strongloop/loopback-context/issues/6
+  it('checks whether context is active', function(done) {
+    var app = loopback();
+
+    app.enableAuth();
+    app.use(contextMiddleware());
+    app.use(session({
+      secret: 'kitty',
+      saveUninitialized: true,
+      resave: true,
+    }));
+    app.use(loopback.token({ model: Token }));
+    app.get('/', function(req, res) { res.send('OK'); });
+    app.use(loopback.rest());
+
+    request(app)
+      .get('/')
+      .set('authorization', this.token.id)
+      .set('cookie', 'connect.sid=s%3AFTyno9_MbGTJuOwdh9bxsYCVxlhlulTZ.' +
+        'PZvp85jzLXZBCBkhCsSfuUjhij%2Fb0B1K2RYZdxSQU0c')
+      .expect(200, 'OK')
+      .end(done);
+  });
 });
 
 function createTestingToken(done) {