mirror of
https://github.com/encode/django-rest-framework.git
synced 2024-11-26 11:33:59 +03:00
635 lines
22 KiB
Python
635 lines
22 KiB
Python
"""
|
|
Renderers are used to serialize a response into specific media types.
|
|
|
|
They give us a generic way of being able to handle various media types
|
|
on the response, such as JSON encoded data or HTML output.
|
|
|
|
REST framework also provides an HTML renderer the renders the browsable API.
|
|
"""
|
|
from __future__ import unicode_literals
|
|
|
|
import copy
|
|
import json
|
|
from django import forms
|
|
from django.core.exceptions import ImproperlyConfigured
|
|
from django.http.multipartparser import parse_header
|
|
from django.template import RequestContext, loader, Template
|
|
from django.test.client import encode_multipart
|
|
from django.utils.xmlutils import SimplerXMLGenerator
|
|
from rest_framework.compat import StringIO
|
|
from rest_framework.compat import six
|
|
from rest_framework.compat import smart_text
|
|
from rest_framework.compat import yaml
|
|
from rest_framework.settings import api_settings
|
|
from rest_framework.request import is_form_media_type, override_method
|
|
from rest_framework.utils import encoders
|
|
from rest_framework.utils.breadcrumbs import get_breadcrumbs
|
|
from rest_framework import exceptions, status, VERSION
|
|
|
|
|
|
class BaseRenderer(object):
|
|
"""
|
|
All renderers should extend this class, setting the `media_type`
|
|
and `format` attributes, and override the `.render()` method.
|
|
"""
|
|
|
|
media_type = None
|
|
format = None
|
|
charset = 'utf-8'
|
|
render_style = 'text'
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
raise NotImplemented('Renderer class requires .render() to be implemented')
|
|
|
|
|
|
class JSONRenderer(BaseRenderer):
|
|
"""
|
|
Renderer which serializes to JSON.
|
|
Applies JSON's backslash-u character escaping for non-ascii characters.
|
|
"""
|
|
|
|
media_type = 'application/json'
|
|
format = 'json'
|
|
encoder_class = encoders.JSONEncoder
|
|
ensure_ascii = True
|
|
charset = None
|
|
# JSON is a binary encoding, that can be encoded as utf-8, utf-16 or utf-32.
|
|
# See: http://www.ietf.org/rfc/rfc4627.txt
|
|
# Also: http://lucumr.pocoo.org/2013/7/19/application-mimetypes-and-encodings/
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Render `data` into JSON.
|
|
"""
|
|
if data is None:
|
|
return bytes()
|
|
|
|
# If 'indent' is provided in the context, then pretty print the result.
|
|
# E.g. If we're being called by the BrowsableAPIRenderer.
|
|
renderer_context = renderer_context or {}
|
|
indent = renderer_context.get('indent', None)
|
|
|
|
if accepted_media_type:
|
|
# If the media type looks like 'application/json; indent=4',
|
|
# then pretty print the result.
|
|
base_media_type, params = parse_header(accepted_media_type.encode('ascii'))
|
|
indent = params.get('indent', indent)
|
|
try:
|
|
indent = max(min(int(indent), 8), 0)
|
|
except (ValueError, TypeError):
|
|
indent = None
|
|
|
|
ret = json.dumps(data, cls=self.encoder_class,
|
|
indent=indent, ensure_ascii=self.ensure_ascii)
|
|
|
|
# On python 2.x json.dumps() returns bytestrings if ensure_ascii=True,
|
|
# but if ensure_ascii=False, the return type is underspecified,
|
|
# and may (or may not) be unicode.
|
|
# On python 3.x json.dumps() returns unicode strings.
|
|
if isinstance(ret, six.text_type):
|
|
return bytes(ret.encode('utf-8'))
|
|
return ret
|
|
|
|
|
|
class UnicodeJSONRenderer(JSONRenderer):
|
|
ensure_ascii = False
|
|
"""
|
|
Renderer which serializes to JSON.
|
|
Does *not* apply JSON's character escaping for non-ascii characters.
|
|
"""
|
|
|
|
|
|
class JSONPRenderer(JSONRenderer):
|
|
"""
|
|
Renderer which serializes to json,
|
|
wrapping the json output in a callback function.
|
|
"""
|
|
|
|
media_type = 'application/javascript'
|
|
format = 'jsonp'
|
|
callback_parameter = 'callback'
|
|
default_callback = 'callback'
|
|
charset = 'utf-8'
|
|
|
|
def get_callback(self, renderer_context):
|
|
"""
|
|
Determine the name of the callback to wrap around the json output.
|
|
"""
|
|
request = renderer_context.get('request', None)
|
|
params = request and request.QUERY_PARAMS or {}
|
|
return params.get(self.callback_parameter, self.default_callback)
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Renders into jsonp, wrapping the json output in a callback function.
|
|
|
|
Clients may set the callback function name using a query parameter
|
|
on the URL, for example: ?callback=exampleCallbackName
|
|
"""
|
|
renderer_context = renderer_context or {}
|
|
callback = self.get_callback(renderer_context)
|
|
json = super(JSONPRenderer, self).render(data, accepted_media_type,
|
|
renderer_context)
|
|
return callback.encode(self.charset) + b'(' + json + b');'
|
|
|
|
|
|
class XMLRenderer(BaseRenderer):
|
|
"""
|
|
Renderer which serializes to XML.
|
|
"""
|
|
|
|
media_type = 'application/xml'
|
|
format = 'xml'
|
|
charset = 'utf-8'
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Renders *obj* into serialized XML.
|
|
"""
|
|
if data is None:
|
|
return ''
|
|
|
|
stream = StringIO()
|
|
|
|
xml = SimplerXMLGenerator(stream, self.charset)
|
|
xml.startDocument()
|
|
xml.startElement("root", {})
|
|
|
|
self._to_xml(xml, data)
|
|
|
|
xml.endElement("root")
|
|
xml.endDocument()
|
|
return stream.getvalue()
|
|
|
|
def _to_xml(self, xml, data):
|
|
if isinstance(data, (list, tuple)):
|
|
for item in data:
|
|
xml.startElement("list-item", {})
|
|
self._to_xml(xml, item)
|
|
xml.endElement("list-item")
|
|
|
|
elif isinstance(data, dict):
|
|
for key, value in six.iteritems(data):
|
|
xml.startElement(key, {})
|
|
self._to_xml(xml, value)
|
|
xml.endElement(key)
|
|
|
|
elif data is None:
|
|
# Don't output any value
|
|
pass
|
|
|
|
else:
|
|
xml.characters(smart_text(data))
|
|
|
|
|
|
class YAMLRenderer(BaseRenderer):
|
|
"""
|
|
Renderer which serializes to YAML.
|
|
"""
|
|
|
|
media_type = 'application/yaml'
|
|
format = 'yaml'
|
|
encoder = encoders.SafeDumper
|
|
charset = 'utf-8'
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Renders *obj* into serialized YAML.
|
|
"""
|
|
assert yaml, 'YAMLRenderer requires pyyaml to be installed'
|
|
|
|
if data is None:
|
|
return ''
|
|
|
|
return yaml.dump(data, stream=None, encoding=self.charset, Dumper=self.encoder)
|
|
|
|
|
|
class TemplateHTMLRenderer(BaseRenderer):
|
|
"""
|
|
An HTML renderer for use with templates.
|
|
|
|
The data supplied to the Response object should be a dictionary that will
|
|
be used as context for the template.
|
|
|
|
The template name is determined by (in order of preference):
|
|
|
|
1. An explicit `.template_name` attribute set on the response.
|
|
2. An explicit `.template_name` attribute set on this class.
|
|
3. The return result of calling `view.get_template_names()`.
|
|
|
|
For example:
|
|
data = {'users': User.objects.all()}
|
|
return Response(data, template_name='users.html')
|
|
|
|
For pre-rendered HTML, see StaticHTMLRenderer.
|
|
"""
|
|
|
|
media_type = 'text/html'
|
|
format = 'html'
|
|
template_name = None
|
|
exception_template_names = [
|
|
'%(status_code)s.html',
|
|
'api_exception.html'
|
|
]
|
|
charset = 'utf-8'
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Renders data to HTML, using Django's standard template rendering.
|
|
|
|
The template name is determined by (in order of preference):
|
|
|
|
1. An explicit .template_name set on the response.
|
|
2. An explicit .template_name set on this class.
|
|
3. The return result of calling view.get_template_names().
|
|
"""
|
|
renderer_context = renderer_context or {}
|
|
view = renderer_context['view']
|
|
request = renderer_context['request']
|
|
response = renderer_context['response']
|
|
|
|
if response.exception:
|
|
template = self.get_exception_template(response)
|
|
else:
|
|
template_names = self.get_template_names(response, view)
|
|
template = self.resolve_template(template_names)
|
|
|
|
context = self.resolve_context(data, request, response)
|
|
return template.render(context)
|
|
|
|
def resolve_template(self, template_names):
|
|
return loader.select_template(template_names)
|
|
|
|
def resolve_context(self, data, request, response):
|
|
if response.exception:
|
|
data['status_code'] = response.status_code
|
|
return RequestContext(request, data)
|
|
|
|
def get_template_names(self, response, view):
|
|
if response.template_name:
|
|
return [response.template_name]
|
|
elif self.template_name:
|
|
return [self.template_name]
|
|
elif hasattr(view, 'get_template_names'):
|
|
return view.get_template_names()
|
|
raise ImproperlyConfigured('Returned a template response with no template_name')
|
|
|
|
def get_exception_template(self, response):
|
|
template_names = [name % {'status_code': response.status_code}
|
|
for name in self.exception_template_names]
|
|
|
|
try:
|
|
# Try to find an appropriate error template
|
|
return self.resolve_template(template_names)
|
|
except Exception:
|
|
# Fall back to using eg '404 Not Found'
|
|
return Template('%d %s' % (response.status_code,
|
|
response.status_text.title()))
|
|
|
|
|
|
# Note, subclass TemplateHTMLRenderer simply for the exception behavior
|
|
class StaticHTMLRenderer(TemplateHTMLRenderer):
|
|
"""
|
|
An HTML renderer class that simply returns pre-rendered HTML.
|
|
|
|
The data supplied to the Response object should be a string representing
|
|
the pre-rendered HTML content.
|
|
|
|
For example:
|
|
data = '<html><body>example</body></html>'
|
|
return Response(data)
|
|
|
|
For template rendered HTML, see TemplateHTMLRenderer.
|
|
"""
|
|
media_type = 'text/html'
|
|
format = 'html'
|
|
charset = 'utf-8'
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
renderer_context = renderer_context or {}
|
|
response = renderer_context['response']
|
|
|
|
if response and response.exception:
|
|
request = renderer_context['request']
|
|
template = self.get_exception_template(response)
|
|
context = self.resolve_context(data, request, response)
|
|
return template.render(context)
|
|
|
|
return data
|
|
|
|
|
|
class HTMLFormRenderer(BaseRenderer):
|
|
"""
|
|
Renderers serializer data into an HTML form.
|
|
|
|
If the serializer was instantiated without an object then this will
|
|
return an HTML form not bound to any object,
|
|
otherwise it will return an HTML form with the appropriate initial data
|
|
populated from the object.
|
|
|
|
Note that rendering of field and form errors is not currently supported.
|
|
"""
|
|
media_type = 'text/html'
|
|
format = 'form'
|
|
template = 'rest_framework/form.html'
|
|
charset = 'utf-8'
|
|
|
|
def data_to_form_fields(self, data):
|
|
fields = {}
|
|
for key, val in data.fields.items():
|
|
if getattr(val, 'read_only', True):
|
|
continue
|
|
|
|
kwargs = {}
|
|
kwargs['required'] = val.required
|
|
|
|
#if getattr(v, 'queryset', None):
|
|
# kwargs['queryset'] = v.queryset
|
|
|
|
if getattr(val, 'choices', None) is not None:
|
|
kwargs['choices'] = val.choices
|
|
|
|
if getattr(val, 'regex', None) is not None:
|
|
kwargs['regex'] = val.regex
|
|
|
|
if getattr(val, 'widget', None):
|
|
widget = copy.deepcopy(val.widget)
|
|
kwargs['widget'] = widget
|
|
|
|
if getattr(val, 'default', None) is not None:
|
|
kwargs['initial'] = val.default
|
|
|
|
if getattr(val, 'label', None) is not None:
|
|
kwargs['label'] = val.label
|
|
|
|
if getattr(val, 'help_text', None) is not None:
|
|
kwargs['help_text'] = val.help_text
|
|
|
|
fields[key] = val.form_field_class(**kwargs)
|
|
|
|
return fields
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Render serializer data and return an HTML form, as a string.
|
|
"""
|
|
# The HTMLFormRenderer currently uses something of a hack to render
|
|
# the content, by translating each of the serializer fields into
|
|
# an html form field, creating a dynamic form using those fields,
|
|
# and then rendering that form.
|
|
|
|
# This isn't strictly neccessary, as we could render the serilizer
|
|
# fields to HTML directly. The implementation is historical and will
|
|
# likely change at some point.
|
|
|
|
self.renderer_context = renderer_context or {}
|
|
request = renderer_context['request']
|
|
|
|
# Creating an on the fly form see:
|
|
# http://stackoverflow.com/questions/3915024/dynamically-creating-classes-python
|
|
fields = self.data_to_form_fields(data)
|
|
DynamicForm = type(str('DynamicForm'), (forms.Form,), fields)
|
|
data = None if data.empty else data
|
|
|
|
template = loader.get_template(self.template)
|
|
context = RequestContext(request, {'form': DynamicForm(data)})
|
|
|
|
return template.render(context)
|
|
|
|
|
|
class BrowsableAPIRenderer(BaseRenderer):
|
|
"""
|
|
HTML renderer used to self-document the API.
|
|
"""
|
|
media_type = 'text/html'
|
|
format = 'api'
|
|
template = 'rest_framework/api.html'
|
|
charset = 'utf-8'
|
|
form_renderer_class = HTMLFormRenderer
|
|
|
|
def get_default_renderer(self, view):
|
|
"""
|
|
Return an instance of the first valid renderer.
|
|
(Don't use another documenting renderer.)
|
|
"""
|
|
renderers = [renderer for renderer in view.renderer_classes
|
|
if not issubclass(renderer, BrowsableAPIRenderer)]
|
|
if not renderers:
|
|
return None
|
|
return renderers[0]()
|
|
|
|
def get_content(self, renderer, data,
|
|
accepted_media_type, renderer_context):
|
|
"""
|
|
Get the content as if it had been rendered by the default
|
|
non-documenting renderer.
|
|
"""
|
|
if not renderer:
|
|
return '[No renderers were found]'
|
|
|
|
renderer_context['indent'] = 4
|
|
content = renderer.render(data, accepted_media_type, renderer_context)
|
|
|
|
render_style = getattr(renderer, 'render_style', 'text')
|
|
assert render_style in ['text', 'binary'], 'Expected .render_style ' \
|
|
'"text" or "binary", but got "%s"' % render_style
|
|
if render_style == 'binary':
|
|
return '[%d bytes of binary content]' % len(content)
|
|
|
|
return content
|
|
|
|
def show_form_for_method(self, view, method, request, obj):
|
|
"""
|
|
Returns True if a form should be shown for this method.
|
|
"""
|
|
if not method in view.allowed_methods:
|
|
return # Not a valid method
|
|
|
|
if not api_settings.FORM_METHOD_OVERRIDE:
|
|
return # Cannot use form overloading
|
|
|
|
try:
|
|
view.check_permissions(request)
|
|
if obj is not None:
|
|
view.check_object_permissions(request, obj)
|
|
except exceptions.APIException:
|
|
return False # Doesn't have permissions
|
|
return True
|
|
|
|
def get_rendered_html_form(self, view, method, request):
|
|
"""
|
|
Return a string representing a rendered HTML form, possibly bound to
|
|
either the input or output data.
|
|
|
|
In the absence of the View having an associated form then return None.
|
|
"""
|
|
with override_method(view, request, method) as request:
|
|
obj = getattr(view, 'object', None)
|
|
if not self.show_form_for_method(view, method, request, obj):
|
|
return
|
|
|
|
if method in ('DELETE', 'OPTIONS'):
|
|
return True # Don't actually need to return a form
|
|
|
|
if (not getattr(view, 'get_serializer', None)
|
|
or not any(is_form_media_type(parser.media_type) for parser in view.parser_classes)):
|
|
return
|
|
|
|
serializer = view.get_serializer(instance=obj)
|
|
data = serializer.data
|
|
form_renderer = self.form_renderer_class()
|
|
return form_renderer.render(data, self.accepted_media_type, self.renderer_context)
|
|
|
|
def get_raw_data_form(self, view, method, request):
|
|
"""
|
|
Returns a form that allows for arbitrary content types to be tunneled
|
|
via standard HTML forms.
|
|
(Which are typically application/x-www-form-urlencoded)
|
|
"""
|
|
with override_method(view, request, method) as request:
|
|
# If we're not using content overloading there's no point in
|
|
# supplying a generic form, as the view won't treat the form's
|
|
# value as the content of the request.
|
|
if not (api_settings.FORM_CONTENT_OVERRIDE
|
|
and api_settings.FORM_CONTENTTYPE_OVERRIDE):
|
|
return None
|
|
|
|
# Check permissions
|
|
obj = getattr(view, 'object', None)
|
|
if not self.show_form_for_method(view, method, request, obj):
|
|
return
|
|
|
|
# If possible, serialize the initial content for the generic form
|
|
default_parser = view.parser_classes[0]
|
|
renderer_class = getattr(default_parser, 'renderer_class', None)
|
|
if (hasattr(view, 'get_serializer') and renderer_class):
|
|
# View has a serializer defined and parser class has a
|
|
# corresponding renderer that can be used to render the data.
|
|
|
|
# Get a read-only version of the serializer
|
|
serializer = view.get_serializer(instance=obj)
|
|
for field_name, field in serializer.fields.items():
|
|
if field.read_only:
|
|
del serializer.fields[field_name]
|
|
|
|
# Render the raw data content
|
|
renderer = renderer_class()
|
|
accepted = self.accepted_media_type
|
|
context = self.renderer_context.copy().update({'indent': 4})
|
|
content = renderer.render(serializer.data, accepted, context)
|
|
else:
|
|
content = None
|
|
|
|
# Generate a generic form that includes a content type field,
|
|
# and a content field.
|
|
content_type_field = api_settings.FORM_CONTENTTYPE_OVERRIDE
|
|
content_field = api_settings.FORM_CONTENT_OVERRIDE
|
|
|
|
media_types = [parser.media_type for parser in view.parser_classes]
|
|
choices = [(media_type, media_type) for media_type in media_types]
|
|
initial = media_types[0]
|
|
|
|
# NB. http://jacobian.org/writing/dynamic-form-generation/
|
|
class GenericContentForm(forms.Form):
|
|
def __init__(self):
|
|
super(GenericContentForm, self).__init__()
|
|
|
|
self.fields[content_type_field] = forms.ChoiceField(
|
|
label='Media type',
|
|
choices=choices,
|
|
initial=initial
|
|
)
|
|
self.fields[content_field] = forms.CharField(
|
|
label='Content',
|
|
widget=forms.Textarea,
|
|
initial=content
|
|
)
|
|
|
|
return GenericContentForm()
|
|
|
|
def get_name(self, view):
|
|
return view.get_view_name()
|
|
|
|
def get_description(self, view):
|
|
return view.get_view_description(html=True)
|
|
|
|
def get_breadcrumbs(self, request):
|
|
return get_breadcrumbs(request.path)
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
"""
|
|
Render the HTML for the browsable API representation.
|
|
"""
|
|
self.accepted_media_type = accepted_media_type or ''
|
|
self.renderer_context = renderer_context or {}
|
|
|
|
view = renderer_context['view']
|
|
request = renderer_context['request']
|
|
response = renderer_context['response']
|
|
|
|
renderer = self.get_default_renderer(view)
|
|
content = self.get_content(renderer, data, accepted_media_type, renderer_context)
|
|
|
|
put_form = self.get_rendered_html_form(view, 'PUT', request)
|
|
post_form = self.get_rendered_html_form(view, 'POST', request)
|
|
patch_form = self.get_rendered_html_form(view, 'PATCH', request)
|
|
delete_form = self.get_rendered_html_form(view, 'DELETE', request)
|
|
options_form = self.get_rendered_html_form(view, 'OPTIONS', request)
|
|
|
|
raw_data_put_form = self.get_raw_data_form(view, 'PUT', request)
|
|
raw_data_post_form = self.get_raw_data_form(view, 'POST', request)
|
|
raw_data_patch_form = self.get_raw_data_form(view, 'PATCH', request)
|
|
raw_data_put_or_patch_form = raw_data_put_form or raw_data_patch_form
|
|
|
|
name = self.get_name(view)
|
|
description = self.get_description(view)
|
|
breadcrumb_list = self.get_breadcrumbs(request)
|
|
|
|
template = loader.get_template(self.template)
|
|
context = RequestContext(request, {
|
|
'content': content,
|
|
'view': view,
|
|
'request': request,
|
|
'response': response,
|
|
'description': description,
|
|
'name': name,
|
|
'version': VERSION,
|
|
'breadcrumblist': breadcrumb_list,
|
|
'allowed_methods': view.allowed_methods,
|
|
'available_formats': [renderer.format for renderer in view.renderer_classes],
|
|
|
|
'put_form': put_form,
|
|
'post_form': post_form,
|
|
'patch_form': patch_form,
|
|
'delete_form': delete_form,
|
|
'options_form': options_form,
|
|
|
|
'raw_data_put_form': raw_data_put_form,
|
|
'raw_data_post_form': raw_data_post_form,
|
|
'raw_data_patch_form': raw_data_patch_form,
|
|
'raw_data_put_or_patch_form': raw_data_put_or_patch_form,
|
|
|
|
'api_settings': api_settings
|
|
})
|
|
|
|
ret = template.render(context)
|
|
|
|
# Munge DELETE Response code to allow us to return content
|
|
# (Do this *after* we've rendered the template so that we include
|
|
# the normal deletion response code in the output)
|
|
if response.status_code == status.HTTP_204_NO_CONTENT:
|
|
response.status_code = status.HTTP_200_OK
|
|
|
|
return ret
|
|
|
|
|
|
class MultiPartRenderer(BaseRenderer):
|
|
media_type = 'multipart/form-data; boundary=BoUnDaRyStRiNg'
|
|
format = 'multipart'
|
|
charset = 'utf-8'
|
|
BOUNDARY = 'BoUnDaRyStRiNg'
|
|
|
|
def render(self, data, accepted_media_type=None, renderer_context=None):
|
|
return encode_multipart(self.BOUNDARY, data)
|
|
|