# -*- coding: utf-8 -*- """ License: BSD (c) 2005-2008 ::: Alec Thomas (alec@swapoff.org) (c) 2009 ::: www.CodeResort.com - BV Network AS (simon-code@bvnetwork.no) """ import inspect import types from datetime import datetime import xmlrpclib from trac.core import * from trac.perm import IPermissionRequestor __all__ = ['expose_rpc', 'IRPCProtocol', 'IXMLRPCHandler', 'AbstractRPCHandler', 'Method', 'XMLRPCSystem', 'Binary', 'RPCError', 'MethodNotFound', 'ProtocolException', 'ServiceException'] class Binary(xmlrpclib.Binary): """ RPC Binary type. Currently == xmlrpclib.Binary. """ pass #---------------------------------------------------------------- # RPC Exception classes #---------------------------------------------------------------- class RPCError(TracError): """ Error class for general RPC-related errors. """ class MethodNotFound(RPCError): """ Error to raise when requested method is not found. """ class _CompositeRpcError(RPCError): def __init__(self, details, title=None, show_traceback=False): if isinstance(details, Exception): self._exc = details message = unicode(details) else : self._exc = None message = details RPCError.__init__(self, message, title, show_traceback) def __unicode__(self): return u"%s details : %s" % (self.__class__.__name__, self.message) class ProtocolException(_CompositeRpcError): """Protocol could not handle RPC request. Usually this means that the request has some sort of syntactic error, a library needed to parse the RPC call is not available, or similar errors.""" class ServiceException(_CompositeRpcError): """The called method threw an exception. Helpful to identify bugs ;o)""" RPC_TYPES = {int: 'int', bool: 'boolean', str: 'string', float: 'double', datetime: 'dateTime.iso8601', Binary: 'base64', list: 'array', dict: 'struct', None : 'int'} def expose_rpc(permission, return_type, *arg_types): """ Decorator for exposing a method as an RPC call with the given signature. """ def decorator(func): if not hasattr(func, '_xmlrpc_signatures'): func._xmlrpc_signatures = [] func._xml_rpc_permission = permission func._xmlrpc_signatures.append((return_type,) + tuple(arg_types)) return func return decorator class IRPCProtocol(Interface): def rpc_info(): """ Returns a tuple of (name, docs). Method provides general information about the protocol used for the RPC HTML view. name: Shortname like 'XML-RPC'. docs: Documentation for the protocol. """ def rpc_match(): """ Return an iterable of (path_item, content_type) combinations that will be handled by the protocol. path_item: Single word to use for matching against (/login)?/. Answer to 'rpc' only if possible. content_type: Starts-with check of 'Content-Type' request header. """ def parse_rpc_request(req, content_type): """ Parse RPC requests. req : HTTP request object content_type : Input MIME type Return a dictionary with the following keys set. All the other values included in this mapping will be ignored by the core RPC subsystem, will be protocol-specific, and SHOULD NOT be needed in order to invoke a given method. method (MANDATORY): target method name (e.g. 'ticket.get') params (OPTIONAL) : a tuple containing input positional arguments headers (OPTIONAL) : if the protocol supports custom headers set by the client, then this value SHOULD be a dictionary binding `header name` to `value`. However, protocol handlers as well as target RPC methods *MUST (SHOULD ?) NOT* rely on specific values assigned to a particular header in order to send a response back to the client. mimetype : request MIME-type. This value will be set by core RPC components after calling this method so, please, ignore If the request cannot be parsed this method *MUST* raise an instance of `ProtocolException` optionally wrapping another exception containing details about the failure. """ def send_rpc_result(req, result): """Serialize the result of the RPC call and send it back to the client. req : Request object. The same mapping returned by `parse_rpc_request` can be accessed through `req.rpc` (see above). result : The value returned by the target RPC method """ def send_rpc_error(req, rpcreq, e): """Send a fault message back to the caller. Exception type and message are used for this purpose. This method *SHOULD* handle `RPCError`, `PermissionError`, `ResourceNotFound` and their subclasses. This method is *ALWAYS* called from within an exception handler. req : Request object. The same mapping returned by `parse_rpc_request` can be accessed through `req.rpc` (see above). e : exception object describing the failure """ class IXMLRPCHandler(Interface): def xmlrpc_namespace(): """ Provide the namespace in which a set of methods lives. This can be overridden if the 'name' element is provided by xmlrpc_methods(). """ def xmlrpc_methods(): """ Return an iterator of (permission, signatures, callable[, name]), where callable is exposed via XML-RPC if the authenticated user has the appropriate permission. The callable itself can be a method or a normal method. The first argument passed will always be a request object. The XMLRPCSystem performs some extra magic to remove the "self" and "req" arguments when listing the available methods. Signatures is a list of XML-RPC introspection signatures for this method. Each signature is a tuple consisting of the return type followed by argument types. """ class AbstractRPCHandler(Component): implements(IXMLRPCHandler) abstract = True def _init_methods(self): self._rpc_methods = [] for name, val in inspect.getmembers(self): if hasattr(val, '_xmlrpc_signatures'): self._rpc_methods.append((val._xml_rpc_permission, val._xmlrpc_signatures, val, name)) def xmlrpc_methods(self): if not hasattr(self, '_rpc_methods'): self._init_methods() return self._rpc_methods class Method(object): """ Represents an XML-RPC exposed method. """ def __init__(self, provider, permission, signatures, callable, name = None): """ Accept a signature in the form returned by xmlrpc_methods. """ self.permission = permission self.callable = callable self.rpc_signatures = signatures self.description = inspect.getdoc(callable) if name is None: self.name = provider.xmlrpc_namespace() + '.' + callable.__name__ else: self.name = provider.xmlrpc_namespace() + '.' + name self.namespace = provider.xmlrpc_namespace() self.namespace_description = inspect.getdoc(provider) def __call__(self, req, args): if self.permission: req.perm.assert_permission(self.permission) result = self.callable(req, *args) # If result is null, return a zero if result is None: result = 0 elif isinstance(result, dict): pass elif not isinstance(result, basestring): # Try and convert result to a list try: result = [i for i in result] except TypeError: pass return (result,) def _get_signature(self): """ Return the signature of this method. """ if hasattr(self, '_signature'): return self._signature fullargspec = inspect.getargspec(self.callable) argspec = fullargspec[0] assert argspec[0:2] == ['self', 'req'] or argspec[0] == 'req', \ 'Invalid argspec %s for %s' % (argspec, self.name) while argspec and (argspec[0] in ('self', 'req')): argspec.pop(0) argspec.reverse() defaults = fullargspec[3] if not defaults: defaults = [] else: defaults = list(defaults) args = [] sig = [] for sigcand in self.xmlrpc_signatures(): if len(sig) < len(sigcand): sig = sigcand sig = list(sig) for arg in argspec: if defaults: value = defaults.pop() if type(value) is str: if '"' in value: value = "'%s'" % value else: value = '"%s"' % value arg += '=%s' % value args.insert(0, RPC_TYPES[sig.pop()] + ' ' + arg) self._signature = '%s %s(%s)' % (RPC_TYPES[sig.pop()], self.name, ', '.join(args)) return self._signature signature = property(_get_signature) def xmlrpc_signatures(self): """ Signature as an XML-RPC 'signature'. """ return self.rpc_signatures class XMLRPCSystem(Component): """ Core of the RPC system. """ implements(IPermissionRequestor, IXMLRPCHandler) method_handlers = ExtensionPoint(IXMLRPCHandler) def __init__(self): self.env.systeminfo.append(('RPC', __import__('tracrpc', ['__version__']).__version__)) # IPermissionRequestor methods def get_permission_actions(self): yield 'XML_RPC' # IXMLRPCHandler methods def xmlrpc_namespace(self): return 'system' def xmlrpc_methods(self): yield ('XML_RPC', ((list, list),), self.multicall) yield ('XML_RPC', ((list,),), self.listMethods) yield ('XML_RPC', ((str, str),), self.methodHelp) yield ('XML_RPC', ((list, str),), self.methodSignature) yield ('XML_RPC', ((list,),), self.getAPIVersion) def get_method(self, method): """ Get an RPC signature by full name. """ for provider in self.method_handlers: for candidate in provider.xmlrpc_methods(): #self.env.log.debug(candidate) p = Method(provider, *candidate) if p.name == method: return p raise MethodNotFound('RPC method "%s" not found' % method) # Exported methods def all_methods(self, req): """ List all methods exposed via RPC. Returns a list of Method objects. """ for provider in self.method_handlers: for candidate in provider.xmlrpc_methods(): # Expand all fields of method description yield Method(provider, *candidate) def multicall(self, req, signatures): """ Takes an array of RPC calls encoded as structs of the form (in a Pythonish notation here): `{'methodName': string, 'params': array}`. For JSON-RPC multicall, signatures is an array of regular method call structs, and result is an array of return structures. """ for signature in signatures: try: yield self.get_method(signature['methodName'])(req, signature['params']) except Exception, e: yield e def listMethods(self, req): """ This method returns a list of strings, one for each (non-system) method supported by the RPC server. """ for method in self.all_methods(req): yield method.name def methodHelp(self, req, method): """ This method takes one parameter, the name of a method implemented by the RPC server. It returns a documentation string describing the use of that method. If no such string is available, an empty string is returned. The documentation string may contain HTML markup. """ p = self.get_method(method) return '\n'.join((p.signature, '', p.description)) def methodSignature(self, req, method): """ This method takes one parameter, the name of a method implemented by the RPC server. It returns an array of possible signatures for this method. A signature is an array of types. The first of these types is the return type of the method, the rest are parameters. """ p = self.get_method(method) return [','.join([RPC_TYPES[x] for x in sig]) for sig in p.xmlrpc_signatures()] def getAPIVersion(self, req): """ Returns a list with three elements. First element is the epoch (0=Trac 0.10, 1=Trac 0.11 or higher). Second element is the major version number, third is the minor. Changes to the major version indicate API breaking changes, while minor version changes are simple additions, bug fixes, etc. """ import tracrpc return map(int, tracrpc.__version__.split('-')[0].split('.'))