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correctly handle multiple requests in a single POST request, add documentation

Natenom/support-murmur-13-1446181288462
Michael Ziegler 14 years ago
parent
commit
a075c0f13c
  1. 199
      pyweb/extdirect.py

199
pyweb/extdirect.py

@ -2,7 +2,7 @@
# kate: space-indent on; indent-width 4; replace-tabs on;
"""
* Copyright (C) 2010, Michael "Svedrin" Ziegler <diese-addy@funzt-halt.net>
* Copyright (C) 200, Michael "Svedrin" Ziegler <diese-addy@funzt-halt.net>
*
* Mumble-Django is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@ -18,8 +18,16 @@
import simplejson
import inspect
import functools
import traceback
from sys import stderr
from django.http import HttpResponse
from django.conf import settings
from django.conf.urls.defaults import patterns
from django.core.urlresolvers import reverse
from django.utils.datastructures import MultiValueDictKeyError
from django.views.decorators.csrf import csrf_exempt
def getname( cls_or_name ):
if type(cls_or_name) not in ( str, unicode ):
@ -27,66 +35,165 @@ def getname( cls_or_name ):
return cls_or_name
class Provider( object ):
def __init__( self, base_url ):
self.base_url = base_url
self.classes = {}
def register_instance( self, cls_or_name, instance ):
name = getname(cls_or_name)
if name not in self.classes:
raise KeyError(name)
self.classes[ name ][0] = instance
return instance
""" Provider for Ext.Direct. This class handles building API information and
routing requests to the appropriate functions, and serializing their
response and exceptions - if any.
Instantiation:
>>> EXT_JS_PROVIDER = Provider( [name="Ext.app.REMOTING_API"] )
After instantiating the Provider, register functions to it like so:
>>> @EXT_JS_PROVIDER.register_method("myclass")
def myview( request, possibly, some, other, arguments ):
" does something with all those args and returns something "
return 13.37
Note that those views **MUST NOT** return an HttpResponse but simply
the plain result, as the Provider will build a response from whatever
your view returns!
To be able to access the Provider, include its URLs in an arbitrary
URL pattern, like so:
>>> from views import EXT_JS_PROVIDER # import our provider instance
>>> urlpatterns = patterns(
# other patterns go here
( r'api/', include(EXT_DIRECT_PROVIDER.urls) ),
)
This way, the Provider will define the URLs "api/api.js" and "api/router".
If you then access the "api/api.js" URL, you will get a response such as:
Ext.app.REMOTING_API = { # Ext.app.REMOTING_API is from Provider.name
"url": "/mumble/api/router",
"type": "remoting",
"actions": {"myclass": [{"name": "myview", "len": 4}]}
}
You can then use this code in ExtJS to define the Provider there.
"""
def __init__( self, name="Ext.app.REMOTING_API" ):
self.name = name
self.classes = {}
def register_method( self, cls_or_name ):
""" Return a function that takes a method as an argument and adds that to cls_or_name. """
print "REGMETHOD", cls_or_name
clsname = getname(cls_or_name)
if clsname not in self.classes:
self.classes[clsname] = ( None, {} )
self.classes[clsname] = {}
return functools.partial( self._register_method, cls_or_name )
def _register_method( self, cls_or_name, method ):
print "REGREALMETHOD", cls_or_name, method
self.classes[ getname(cls_or_name) ][1][ method.__name__ ] = method
""" Actually registers the given function as a method of cls_or_name. """
self.classes[ getname(cls_or_name) ][ method.__name__ ] = method
return method
def get_api( self, name="Ext.app.REMOTING_API" ):
@csrf_exempt
def get_api( self, request ):
""" Introspect the methods and get a JSON description of this API. """
actdict = {}
for clsname in self.classes:
actdict[clsname] = []
for methodname in self.classes[clsname][1]:
for methodname in self.classes[clsname]:
actdict[clsname].append( {
"name": methodname,
"len": len( inspect.getargspec( self.classes[clsname][1][methodname] ).args )
"len": len( inspect.getargspec( self.classes[clsname][methodname] ).args ) - 1
} )
return "%s = %s" % ( name, simplejson.dumps({
"url": ("%s/router" % self.base_url),
return HttpResponse( "%s = %s;" % ( self.name, simplejson.dumps({
"url": reverse( self.request ),
"type": "remoting",
"actions": actdict
}))
})), mimetype="text/javascript" )
@csrf_exempt
def request( self, request ):
cls = request.POST['extAction']
methname = request.POST['extMethod']
data = request.POST['extData']
rtype = request.POST['extType']
tid = request.POST['extTID']
if cls not in self.classes:
raise KeyError(cls)
if methname not in self.classes[cls][1]:
raise KeyError(methname)
result = self.classes[cls][1][methname]( *data, request=request )
return HttpResponse( simplejson.dumps({
"type": rtype,
"tid": tid,
"action": cls,
"method": methname,
"result": result
}))
""" Implements the Router part of the Ext.Direct specification.
It handles decoding requests, calling the appropriate function (if
found) and encoding the response / exceptions.
"""
try:
rawjson = [{
'action': request.POST['extAction'],
'method': request.POST['extMethod'],
'data': request.POST['extData'],
'type': request.POST['extType'],
'tid': request.POST['extTID'],
}]
except (MultiValueDictKeyError, KeyError):
rawjson = simplejson.loads( request.raw_post_data )
if not isinstance( rawjson, list ):
rawjson = [rawjson]
responses = []
for reqinfo in rawjson:
cls, methname, data, rtype, tid = (reqinfo['action'],
reqinfo['method'],
reqinfo['data'],
reqinfo['type'],
reqinfo['tid'])
if cls not in self.classes:
responses.append({
'type': 'exception',
'message': 'no such action',
'where': cls,
"tid": tid,
})
continue
if methname not in self.classes[cls]:
responses.append({
'type': 'exception',
'message': 'no such method',
'where': methname,
"tid": tid,
})
continue
try:
if data:
result = self.classes[cls][methname]( request, *data )
else:
result = self.classes[cls][methname]( request )
except Exception, err:
errinfo = {
'type': 'exception',
"tid": tid,
}
if settings.DEBUG:
traceback.print_exc( file=stderr )
errinfo['message'] = unicode(err)
errinfo['where'] = '\n'.join(traceback.format_exception())
else:
errinfo['message'] = 'Sorry, an error occurred.'
errinfo['where'] = ''
responses.append(errinfo)
else:
responses.append({
"type": rtype,
"tid": tid,
"action": cls,
"method": methname,
"result": result
})
if len(responses) == 1:
return HttpResponse( simplejson.dumps( responses[0] ), mimetype="text/javascript" )
else:
return HttpResponse( simplejson.dumps( responses ), mimetype="text/javascript" )
@property
def urls(self):
""" Return the URL patterns. """
return patterns('',
(r'api.js$', self.get_api ),
(r'router/?', self.request ),
)
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