From 677216d2c4ddc5f0df857b8f9e8fa6ccfd5fd55a Mon Sep 17 00:00:00 2001 From: Michael Merickel Date: Wed, 18 Apr 2012 00:50:10 -0500 Subject: reverted back to using a component registry during json encoding --- docs/narr/renderers.rst | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-) (limited to 'docs') diff --git a/docs/narr/renderers.rst b/docs/narr/renderers.rst index 02063a112..c36caeb87 100644 --- a/docs/narr/renderers.rst +++ b/docs/narr/renderers.rst @@ -182,10 +182,10 @@ using the API of the ``request.response`` attribute. See JSON Renderer ~~~~~~~~~~~~~ -The ``json`` renderer renders view callable results to :term:`JSON`. It -passes the return value through the ``json.dumps`` standard library function, -and wraps the result in a response object. It also sets the response -content-type to ``application/json``. +The ``json`` renderer renders view callable results to :term:`JSON`. By +default, it passes the return value through the ``json.dumps`` standard +library function, and wraps the result in a response object. It also sets +the response content-type to ``application/json``. Here's an example of a view that returns a dictionary. Since the ``json`` renderer is specified in the configuration for this view, the view will @@ -209,11 +209,11 @@ representing the JSON serialization of the return value: '{"content": "Hello!"}' The return value needn't be a dictionary, but the return value must contain -values serializable by ``json.dumps``. +values serializable by the configured serializer (by default ``json.dumps``). .. note:: - Extra arguments can be passed to ``json.dumps`` by overriding the default + Extra arguments can be passed to the serializer by overriding the default ``json`` renderer. See :class:`pyramid.renderers.JSON` and :ref:`adding_and_overriding_renderers` for more information. @@ -240,8 +240,8 @@ Serializing Custom Objects Custom objects can be made easily JSON-serializable in Pyramid by defining a ``__json__`` method on the object's class. This method should return values -natively serializable by ``json.dumps`` (such as ints, lists, dictionaries, -strings, and so forth). +natively JSON-serializable (such as ints, lists, dictionaries, strings, and +so forth). .. code-block:: python :linenos: @@ -267,22 +267,18 @@ possible (or at least not reasonable) to add a custom ``__json__`` method to to their classes in order to influence serialization. If the object passed to the renderer is not a serializable type, and has no ``__json__`` method, usually a :exc:`TypeError` will be raised during serialization. You can -change this behavior by creating a JSON renderer with a "default" function -which tries to "sniff" at the object, and returns a valid serialization (a -string) or raises a TypeError if it can't determine what to do with the -object. A short example follows: +change this behavior by creating a custom JSON renderer and adding adapters +to handle custom types. The renderer will attempt to adapt non-serializable +objects using the registered adapters. It will raise a :exc:`TypeError` if it +can't determine what to do with the object. A short example follows: .. code-block:: python :linenos: from pyramid.renderers import JSON - def default(obj): - if isinstance(obj, datetime.datetime): - return obj.isoformat() - raise TypeError('%r is not serializable % (obj,)) - - json_renderer = JSON(default=default) + json_renderer = JSON() + json_renderer.add_adapter(datetime.datetime, lambda x: x.isoformat()) # then during configuration .... config = Configurator() -- cgit v1.2.3 From e012aa12760f6c29bfc9967c50a51d3f47db47da Mon Sep 17 00:00:00 2001 From: Chris McDonough Date: Thu, 3 May 2012 02:42:55 -0400 Subject: allow __json__ and custom adapters to accept request arg --- docs/narr/renderers.rst | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'docs') diff --git a/docs/narr/renderers.rst b/docs/narr/renderers.rst index c36caeb87..57b5bc65b 100644 --- a/docs/narr/renderers.rst +++ b/docs/narr/renderers.rst @@ -241,7 +241,8 @@ Serializing Custom Objects Custom objects can be made easily JSON-serializable in Pyramid by defining a ``__json__`` method on the object's class. This method should return values natively JSON-serializable (such as ints, lists, dictionaries, strings, and -so forth). +so forth). It should accept a single additional argument, ``request``, which +will be the active request object at render time. .. code-block:: python :linenos: @@ -252,7 +253,7 @@ so forth). def __init__(self, x): self.x = x - def __json__(self): + def __json__(self, request): return {'x':self.x} @view_config(renderer='json') @@ -269,8 +270,7 @@ to the renderer is not a serializable type, and has no ``__json__`` method, usually a :exc:`TypeError` will be raised during serialization. You can change this behavior by creating a custom JSON renderer and adding adapters to handle custom types. The renderer will attempt to adapt non-serializable -objects using the registered adapters. It will raise a :exc:`TypeError` if it -can't determine what to do with the object. A short example follows: +objects using the registered adapters. A short example follows: .. code-block:: python :linenos: @@ -278,12 +278,19 @@ can't determine what to do with the object. A short example follows: from pyramid.renderers import JSON json_renderer = JSON() - json_renderer.add_adapter(datetime.datetime, lambda x: x.isoformat()) + def datetime_adapter(obj, request): + return obj.isoformat() + json_renderer.add_adapter(datetime.datetime, datetime_adapter) # then during configuration .... config = Configurator() config.add_renderer('json', json_renderer) +The adapter should accept two arguments: the object needing to be serialized +and ``request``, which will be the current request object at render time. +The adapter should raise a :exc:`TypeError` if it can't determine what to do +with the object. + See :class:`pyramid.renderers.JSON` and :ref:`adding_and_overriding_renderers` for more information. -- cgit v1.2.3