added --use-async option: generate async handlers (tornado)

swagger_py_codegen/command.py

@@ -162,9 +162,11 @@ def print_version(ctx, param, value):
 @click.option('--version', is_flag=True, callback=print_version,
               expose_value=False, is_eager=True,
               help='Show current version.')
+@click.option('-a', '--use-async', default=False, is_flag=True,
+              help='Generate async request handlers (tornado)')
 def generate(destination, swagger_doc, force=False, package=None,
              template_dir=None, templates='flask',
-             specification=False, ui=False, validate=False):
+             specification=False, ui=False, validate=False, use_async=False):
     package = package or destination.replace('-', '_')
     data = spec_load(swagger_doc)
     if validate:
@@ -198,6 +200,7 @@ def generate(destination, swagger_doc, force=False, package=None,
         click.secho('%-12s%s' % (status, ui_dest))
 
     for code in generator.generate():
+        code.data['use_async'] = use_async
         source = template.render_code(code)
         dest = join(destination, code.dest(env))
         dest_exists = exists(dest)

swagger_py_codegen/templates/tornado/validators.tpl

@@ -71,7 +71,11 @@ class ValidatorAdaptor(object):
 def request_validate(obj):
     def _request_validate(view):
         @wraps(view)
+        {% if not use_async -%}
         def wrapper(*args, **kwargs):
+        {%- else -%}
+        async def wrapper(*args, **kwargs):
+        {%- endif %}
             request = obj.request
             endpoint = obj.endpoint
             user_info = obj.current_user
@@ -88,7 +92,8 @@ def request_validate(obj):
                 if location == 'json':
                     value = getattr(request, 'body', MultiDict())
                 elif location == 'args':
-                    value = getattr(request, 'query_arguments', MultiDict())
+                    value = {key: list(map(obj.decode_argument, value)) for key, value in
+                             request.query_arguments.items()}
                     for k,v in six.iteritems(value):
                         if isinstance(v, list) and len(v) == 1:
                             value[k] = v[0]
@@ -101,16 +106,25 @@ def request_validate(obj):
                     raise tornado.web.HTTPError(422, message='Unprocessable Entity',
                                                 reason=json.dumps(reasons))
                 setattr(obj, location, result)
+            {% if not use_async -%}
             return view(*args, **kwargs)
+            {%- else -%}
+            return await view(*args, **kwargs)
+            {%- endif %}
         return wrapper
     return _request_validate
 
 
 def response_filter(obj):
     def _response_filter(view):
         @wraps(view)
+        {% if not use_async -%}
         def wrapper(*args, **kwargs):
             resp = view(*args, **kwargs)
+        {%- else -%}
+        async def wrapper(*args, **kwargs):
+            resp = await view(*args, **kwargs)
+        {%- endif %}
             request = obj.request
             endpoint = obj.endpoint
             method = request.method
@@ -145,7 +159,8 @@ def response_filter(obj):
                         reason=json.dumps(errors))
             obj.set_status(status)
             obj.set_headers(headers)
-            obj.write(json.dumps(resp))
+            if resp:
+                obj.write(json.dumps(resp))
             return
         return wrapper
     return _response_filter

swagger_py_codegen/templates/tornado/view.tpl

@@ -9,7 +9,11 @@ class {{ name }}(ApiHandler):
 
     {%- for method, ins in methods.items() %}
 
+    {% if use_async -%}
+    async def {{ method.lower() }}(self{{ params.__len__() and ', ' or '' }}{{ params | join(', ') }}):
+    {%- else -%}
     def {{ method.lower() }}(self{{ params.__len__() and ', ' or '' }}{{ params | join(', ') }}):
+    {%- endif %}
         {%- for request in ins.requests %}
         print(self.{{ request }})
         {%- endfor %}