diff options
Diffstat (limited to 'src/lib')
| -rw-r--r-- | src/lib/Client/Proxy.py | 92 | ||||
| -rw-r--r-- | src/lib/Client/__init__.py | 2 |
2 files changed, 93 insertions, 1 deletions
diff --git a/src/lib/Client/Proxy.py b/src/lib/Client/Proxy.py new file mode 100644 index 000000000..d300eac72 --- /dev/null +++ b/src/lib/Client/Proxy.py @@ -0,0 +1,92 @@ +'''Cobalt proxy provides client access to cobalt components''' +__revision__ = '$Revision:$' + +import logging, socket, time, xmlrpclib, ConfigParser + +class CobaltComponentError(Exception): + '''This error signals component connection errors''' + pass + +class SafeProxy: + '''Wrapper for proxy''' + _cfile = ConfigParser.ConfigParser() + _cfile.read(['/etc/cobalt.conf']) + _components = _cfile._sections['components'] + _authinfo = ('root', _cfile.get('communication', 'password')) + _retries = 4 + + def __init__(self, component, url=None): + self.component = component + self.log = logging.getLogger(component) + if url != None: + address = url + else: + address = self.__get_location(component) + try: + self.proxy = xmlrpclib.ServerProxy(address) + except IOError, io_error: + self.log.error("Invalid server URL %s: %s" % (address, io_error)) + raise CobaltComponentError + except: + self.log.error("Failed to initialize xml-rpc", exc_info=1) + + def run_method(self, method_name, method_args): + ''' Perform an XMLRPC invocation against the server''' + method = getattr(self.proxy, method_name) + for irs in range(self._retries): + try: + ret = apply(method, self._authinfo + method_args) + if irs > 0: + self.log.warning("Required %d attempts to contact %s for operation %s" % + (irs, self.component, method_name)) + self.log.debug("%s completed successfully" % (method_name)) + return ret + except xmlrpclib.ProtocolError: + self.log.error("Server failure: Protocol Error") + raise xmlrpclib.Fault(20, "Server Failure") + except xmlrpclib.Fault: + self.log.debug("Operation %s completed with fault" % (method_name)) + raise + except socket.error: + self.log.debug("Attempting %s (%d of %d) failed" % (method_name, (irs+1), self._retries)) + time.sleep(0.5) + except: + break + self.log.error("%s failed:\nCould not connect to %s" % (method_name, self.component)) + + def __get_location(self, name): + '''Perform component location lookups if needed''' + if self._components.has_key(name): + return self._components[name] + slp = SafeProxy('service-location', url=self._cfile.get('components', 'service-location')) + try: + sdata = slp.run_method('LookupService', + ([{'tag':'location', 'name':name, 'url':'*'}],)) + except xmlrpclib.Fault: + raise CobaltComponentError, "No Such Component" + if sdata: + curl = sdata[0]['url'] + self._components[name] = curl + return curl + +class ComponentProxy(SafeProxy): + '''Component Proxy instantiates a SafeProxy to a component and registers local functions + based on its definition''' + name = 'dummy' + methods = [] + + def __init__(self, url=None): + SafeProxy.__init__(self, self.name, url) + for method in self.methods: + setattr(self, method, eval('lambda *x:self.run_method(method, x)', + {'self':self, 'method':method})) + +class service_location(ComponentProxy): + '''service-location component-specific proxy''' + name = 'service-location' + methods = ['AssertService', 'LookupService', 'DeassertService'] + +class process_manager(ComponentProxy): + '''process manager specific component proxy''' + name = 'process-manager' + methods = ['CreateProcessGroup', 'GetProcessGroup'] diff --git a/src/lib/Client/__init__.py b/src/lib/Client/__init__.py index 0435249f7..bfdbc0e98 100644 --- a/src/lib/Client/__init__.py +++ b/src/lib/Client/__init__.py @@ -1,4 +1,4 @@ '''This contains all Bcfg2 Client modules''' __revision__ = '$Revision$' -__all__ = ["Toolset", "Debian", "Solaris", "Redhat", "Gentoo"] +__all__ = ["Proxy", "Toolset", "Debian", "Solaris", "Redhat", "Gentoo"] |