pass context to response schema validation

API.md

@@ -2148,10 +2148,10 @@ following options:
       expressed as one of:
         - `true` - any payload allowed (no validation performed). This is the default.
         - `false` - no payload allowed.
-        - a [Joi](http://github.com/hapijs/joi) validation object.
+        - a [Joi](http://github.com/hapijs/joi) validation object. This will receive the request's headers, params, query, payload, and auth credentials and isAuthenticated flags as context.
         - a validation function using the signature `function(value, options, next)` where:
             - `value` - the object containing the response object.
-            - `options` - the server validation options.
+            - `options` - the server validation options, merged with an object containing the request's headers, params, payload, and auth credentials object and isAuthenticated flag.
             - `next(err)` - the callback function called when validation is completed.
     - `status` - HTTP status-code-specific validation rules. The `status` key is set to an
       object where each key is a 3 digit HTTP status code and the value has the same

lib/validation.js

@@ -194,12 +194,27 @@ exports.response = function (request, next) {
         return next(Boom.badImplementation(err.message));
     };
 
+    var localOptions = {
+        context: {
+            headers: request.headers,
+            params: request.params,
+            query: request.query,
+            payload: request.payload,
+            auth: {
+                isAuthenticated: request.auth.isAuthenticated,
+                credentials: request.auth.credentials
+            }
+        }
+    };
+
+    Hoek.merge(localOptions, request.route.settings.response.options);
+
     if (typeof schema !== 'function') {
-        return Joi.validate(source, schema, request.route.settings.response.options, postValidate);
+        return Joi.validate(source, schema, localOptions, postValidate);
     }
 
     request._protect.run('validate:response', postValidate, function (exit) {
 
-        return schema(source, request.route.settings.response.options, exit);
+        return schema(source, localOptions, exit);
     });
 };

test/validation.js

@@ -753,6 +753,43 @@ describe('validation', function () {
         });
     });
 
+    it('validates response with context', function (done) {
+
+        var i = 0;
+        var handler = function (request, reply) {
+
+            return reply({ some: 'thing', more: 'stuff' });
+        };
+
+        var server = new Hapi.Server({ debug: false });
+        server.connection();
+        server.route({
+            method: 'GET',
+            path: '/',
+            config: {
+                response: {
+                    schema: Joi.object({
+                        some: Joi.string(),
+                        more: Joi.string()
+                    }).when('$query.user', { is: 'admin', otherwise: Joi.object({ more: Joi.forbidden() }) })
+                }
+            },
+            handler: handler
+        });
+
+        server.inject('/?user=admin', function (res) {
+
+            expect(res.statusCode).to.equal(200);
+            expect(res.payload).to.equal('{"some":"thing","more":"stuff"}');
+
+            server.inject('/?user=test', function (res) {
+
+                expect(res.statusCode).to.equal(500);
+                done();
+            });
+        });
+    });
+
     it('validates error response', function (done) {
 
         var i = 0;