# # Copyright (c) 2011 Edward Langley # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions # are met: # # Redistributions of source code must retain the above copyright notice, # this list of conditions and the following disclaimer. # # Redistributions in binary form must reproduce the above copyright # notice, this list of conditions and the following disclaimer in the # documentation and/or other materials provided with the distribution. # # Neither the name of the project's author nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS # FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED # TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR # PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF # LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # import jsonrpc.jsonutil from jsonrpc.utilities import public import jsonrpc.common # Twisted imports from twisted.web import server from twisted.internet import threads from twisted.web.resource import Resource import copy import UserDict, collections collections.Mapping.register(UserDict.DictMixin) @public class ServerEvents(object): '''Subclass this and pass to :py:meth:`jsonrpc.customize` to customize the jsonrpc server''' def __init__(self, server): #: A link to the JSON-RPC server instance self.server = server def callmethod(self, txrequest, rpcrequest, **extra): '''Finds the method and calls it with the specified args''' method = self.findmethod(rpcrequest.method) if method is None: raise jsonrpc.common.MethodNotFound extra.update(rpcrequest.kwargs) return method(*rpcrequest.args, **extra) def findmethod(self, method): '''Override to allow server to define methods''' return lambda *a, **kw: 'Test Data' def processrequest(self, result, args, **kw): '''Override to implement custom handling of the method result and request''' return result def log(self, response, txrequest, error=False): '''Override to implement custom error handling''' pass def processcontent(self, content, request): '''Given the freshly decoded content of the request, return what content should be used''' return content ## Base class providing a JSON-RPC 2.0 implementation with 2 customizable hooks @public class JSON_RPC(Resource): '''This class implements a JSON-RPC 2.0 server as a Twisted Resource''' isLeaf = True #: set by :py:meth:`customize` used to change the behavior of the server eventhandler = ServerEvents def customize(self, eventhandler): '''customize the behavior of the server''' self.eventhandler = eventhandler(self) return self def __init__(self, *args, **kwargs): self.customize(self.eventhandler) Resource.__init__(self,*args, **kwargs) def render(self, request): request.content.seek(0, 0) try: try: content = jsonrpc.jsonutil.decode(request.content.read()) except ValueError: raise jsonrpc.common.ParseError content = self.eventhandler.processcontent(content, request) content = jsonrpc.common.Request.from_json(content) try: if hasattr(content, 'check'): content.check() else: for item in content: item.check() except jsonrpc.common.RPCError, e: self._ebRender(e, request, content.id if hasattr(content, 'id') else None) else: d = threads.deferToThread(self._action, request, content) d.addCallback(self._cbRender, request) d.addErrback(self._ebRender, request, content.id if hasattr(content, 'id') else None) except BaseException, e: self._ebRender(e, request, None) return server.NOT_DONE_YET def _action(self, request, contents, **kw): result = [] islist = (True if isinstance(contents, list) else False) if not islist: contents = [contents] if contents == []: raise jsonrpc.common.InvalidRequest for rpcrequest in contents: res = None try: add = copy.deepcopy(rpcrequest.extra) add.update(kw) res = jsonrpc.common.Response(id=rpcrequest.id, result=self.eventhandler.callmethod(request, rpcrequest, **add)) res = self.eventhandler.processrequest(res, request.args, **kw) except Exception, e: res = self.render_error(e, rpcrequest.id) if res.id is not None: result.append(res) if result != []: if not islist: result = result[0] else: result = None return result def _setresponseCode(self, result, request): code = 200 if not isinstance(result, list): if result is not None and result.error is not None: code = 500 request.setResponseCode(code) def _cbRender(self, result, request): self._setresponseCode(result, request) self.eventhandler.log(result, request, error=False) if result is not None: request.setHeader("content-type", 'application/json') result = jsonrpc.jsonutil.encode(result).encode('utf-8') request.setHeader("content-length", len(result)) request.write(result) request.finish() def _ebRender(self, result, request, id, finish=True): err = None if not isinstance(result, BaseException): try: result.raiseException() except BaseException, e: err = e self.eventhandler.log(err, request, error=True) else: err = result err = self.render_error(err, id) self._setresponseCode(err, request) request.setHeader("content-type", 'application/json') result = jsonrpc.jsonutil.encode(err).encode('utf-8') request.setHeader("content-length", len(result)) request.write(result) if finish: request.finish() def render_error(self, e, id): if isinstance(e, jsonrpc.common.RPCError): err = jsonrpc.common.Response(id=id, error=e) else: err = jsonrpc.common.Response(id=id, error=dict(code=0, message=str(e), data=e.args)) return err