Fix `loopback.getCurrentContext`

- ensure the method is always defined

 - return `null` when the context is not active
   (we are not inside a request-handling chain)

lib/loopback.js

@@ -185,6 +185,11 @@ loopback.template = function(file) {
   return ejs.compile(str);
 };
 
+loopback.getCurrentContext = function() {
+  // A placeholder method, see lib/middleware/context.js for the real version
+  return null;
+};
+
 /*!
  * Built in models / services
  */

lib/middleware/context.js

@@ -16,7 +16,7 @@ function createContext(scope) {
     process.context[scope] = ns;
     // Set up loopback.getCurrentContext()
     loopback.getCurrentContext = function() {
-      return ns;
+      return ns && ns.active ? ns : null;
     };
 
     chain(juggler);

test/loopback.test.js

@@ -20,6 +20,10 @@ describe('loopback', function() {
       expect(require('fs').existsSync(loopback.faviconFile), 'file exists')
         .to.equal(true);
     });
+
+    it.onServer('has `getCurrentContext` method', function() {
+      expect(loopback.getCurrentContext).to.be.a('function');
+    });
   });
 
   describe('loopback.createDataSource(options)', function() {