Merge pull request #218 from onefinestay/http_response_type

require string responses for http

docs/built_in_extensions.rst

@@ -76,7 +76,12 @@ Nameko's HTTP entrypoint supports simple GET and POST:
     received: post body
 
 
-The HTTP entrypoint is built on top of `werkzeug <http://werkzeug.pocoo.org/>`_. Service methods can return specific status codes and headers, or a :class:`werkzeug.wrappers.Response` object:
+The HTTP entrypoint is built on top of `werkzeug <http://werkzeug.pocoo.org/>`_. Service methods must return one of:
+
+- a string, which becomes the response body
+- a 2-tuple ``(status code, response body)``
+- a 3-tuple ``(status_code, headers dict, response body)``
+- an instance of :class:`werkzeug.wrappers.Response`
 
 .. literalinclude:: examples/advanced_http.py
 

docs/examples/http.py

@@ -1,12 +1,13 @@
 # http.py
 
+import json
 from nameko.web.handlers import http
 
 class HttpService(object):
 
     @http('GET', '/get/<int:value>')
     def get_method(self, value):
-        return {'value': value}
+        return json.dumps({'value': value})
 
     @http('POST', '/post')
     def do_post(self, body):

nameko/web/handlers.py

@@ -28,8 +28,11 @@ def response_from_result(result):
         payload = result
         status = 200
 
+    if not isinstance(payload, basestring):
+        raise TypeError("Payload must be a string. Got `{!r}`".format(payload))
+
     return Response(
-        unicode(payload),
+        payload,
         status=status,
         headers=headers,
     )

test/web/test_http_handler.py

@@ -57,9 +57,9 @@ def test_get(web_session):
 
 def test_post(web_session):
     rv = web_session.post('/post', json={
-        'value': 23,
+        'value': 'foo',
     })
-    assert rv.text == "23"
+    assert rv.text == "foo"
 
 
 def test_custom_response(web_session):
@@ -90,3 +90,9 @@ def test_broken_method_expected(web_session):
     rv = web_session.get('/fail_expected')
     assert rv.status_code == 400
     assert "ValueError: oops" in rv.text
+
+
+def test_bad_payload(web_session):
+    rv = web_session.post('/post', json={'value': 23})
+    assert rv.status_code == 500
+    assert "Error: TypeError: Payload must be a string. Got `23`" in rv.text