Replace bcfg2 proxy code with simplified code from Cobalt

git-svn-id: https://svn.mcs.anl.gov/repos/bcfg/trunk/bcfg2@4226 ce84e21b-d406-0410-9b95-82705330c041

5 files changed, 191 insertions, 234 deletions

diff --git a/src/lib/Client/Proxy.py b/src/lib/Client/Proxy.py
deleted file mode 100644
index d148748e2..000000000
--- a/src/lib/Client/Proxy.py
+++ /dev/null
@@ -1,231 +0,0 @@
-'''Cobalt proxy provides client access to cobalt components'''
-__revision__ = '$Revision$'
-
-import logging, socket, time, xmlrpclib, ConfigParser, httplib
-from Bcfg2.tlslite.integration.XMLRPCTransport import XMLRPCTransport
-from Bcfg2.tlslite.integration.HTTPTLSConnection import HTTPTLSConnection
-from Bcfg2.tlslite.TLSConnection import TLSConnection
-import Bcfg2.tlslite.errors
-
-#FIXME need to reimplement _binadaddress support for XMLRPCTransport
-
-class MyHTTPTLSConnection(HTTPTLSConnection):
-    def connect(self):
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-        if hasattr(sock, 'settimeout'):
-            sock.settimeout(90)
-        sock.connect((self.host, self.port))
-
-        #Use a TLSConnection to emulate a socket
-        self.sock = TLSConnection(sock)
-
-        #When httplib closes this, close the socket
-        self.sock.closeSocket = True
-        self._handshake(self.sock)
-
-class MyXMLRPCTransport(XMLRPCTransport):
-    def make_connection(self, host):
-        # create a HTTPS connection object from a host descriptor
-        host, extra_headers, x509 = self.get_host_info(host)
-        http = MyHTTPTLSConnection(host, None,
-                                   self.username, self.password,
-                                   self.sharedKey,
-                                   self.certChain, self.privateKey,
-                                   self.checker.cryptoID,
-                                   self.checker.protocol,
-                                   self.checker.x509Fingerprint,
-                                   self.checker.x509TrustList,
-                                   self.checker.x509CommonName,
-                                   self.settings)
-        http2 = httplib.HTTP(host)
-        http2._setup(http)
-        return http2
-
-class CobaltComponentError(Exception):
-    pass
-
-class SafeProxy:
-    '''Wrapper for proxy'''
-               
-    _retries = 4
-    _authinfo = ()
-    _components = {}
-    def __init__(self, component, args={}):
-        self.component = component
-        self.log = logging.getLogger(component)
-
-        if args.has_key('server'):
-            # processing from command line args
-            self._components[component] = args['server']
-        else:
-            if args.has_key('setup'):
-                # processing from specified config file
-                _cfpath = args['setup']
-            else:
-                _cfpath = '/etc/bcfg2.conf'
-            self._cfile = ConfigParser.ConfigParser()
-            self._cfile.read([_cfpath])
-            try:
-                self._components = self._cfile._sections['components']
-            except:
-                self.log.error("%s doesn't contain a valid components section" % (_cfpath))
-                raise SystemExit, 1
-        if args.has_key('password'):
-            # get passwd from cmdline
-            password = args['password']
-        else:
-            try:
-                password = self._cfile.get('communication', 'password')
-            except:
-                self.log.error("%s doesn't contain a valid password" % (_cfpath))
-                raise SystemExit, 1
-        if args.has_key('user'):
-            user = args['user']
-        else:
-            try:
-                user = self._cfile.get('communication', 'user')
-            except:
-                user = 'root'
-            
-        self._authinfo = (user, password)
-
-        if args.has_key('fingerprint'):
-            self.fingerprint = args['fingerprint']
-        else:
-            self.fingerprint = False
-
-        _bindaddress = ""
-        try:
-            _bindaddress = self._cfile.get('communication', 'bindaddress')
-        except:
-            pass
-        
-        if args.has_key('server'):
-            address = args['server']
-        else:
-            address = self.__get_location(component)
-            
-        try:
-            #             if _bindaddress != "":
-            #                 self.log.info("Binding client to address %s" % _bindaddress)
-            #                 self.proxy = xmlrpclib.ServerProxy(address, transport=Bcfg2SafeTransport())
-            #             else:
-            if self.fingerprint:
-                transport = MyXMLRPCTransport(x509Fingerprint=self.fingerprint)
-            else:
-                transport = MyXMLRPCTransport()
-            self.proxy = xmlrpclib.ServerProxy(address, transport=transport)
-
-        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, methodName, methodArgs):
-        ''' Perform an XMLRPC invocation against the server'''
-        method = getattr(self.proxy, methodName)
-        for irs in range(self._retries):
-            try:
-                ret = apply(method, self._authinfo + methodArgs)
-                if irs > 0:
-                    self.log.warning("Required %d attempts to contact %s for operation %s" %
-                                     (irs, self.component, methodName))
-                self.log.debug("%s completed successfully" % (methodName))
-                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" % (methodName))
-                raise
-            except socket.error, serr:
-                self.log.debug("Attempting %s (%d of %d) failed because %s" % (methodName, (irs+1),
-                                                                               self._retries, serr))
-            except Bcfg2.tlslite.errors.TLSFingerprintError, err:
-                self.log.error("Server fingerprint did not match")
-                errmsg = err.message.split()
-                self.log.error("Got %s expected %s" % (errmsg[3], errmsg[4]))
-                raise SystemExit, 1
-            except:
-                self.log.error("Unknown failure", exc_info=1)
-                break
-            time.sleep(0.5)
-        self.log.error("%s failed:\nCould not connect to %s" % (methodName, self.component))
-        raise xmlrpclib.Fault(20, "Server Failure")
-        
-    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
-
-    def dummy(self):
-        '''dummy method for pylint'''
-        return True
-            
-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={}):
-        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 allocation_manager(ComponentProxy):
-    '''allocation manager specific component proxy'''
-    name = 'allocation-manager'
-    methods = ['GetProject']
-
-class file_stager(ComponentProxy):
-    '''File staging component'''
-    name = 'file-stager'
-    methods = ['StageInit', 'FinalizeStage']
-
-class process_manager(ComponentProxy):
-    '''process manager specific component proxy'''
-    name = 'process-manager'
-    methods = ['CreateProcessGroup', 'GetProcessGroup', 'KillProcessGroup', 'WaitProcessGroup']
-
-class queue_manager(ComponentProxy):
-    '''queue manager proxy'''
-    name = 'queue-manager'
-    methods = ['AddJob', 'GetJobs', 'DelJobs', 'RunJobs', 'SetJobs', 'SetJobID']
-
-class scheduler(ComponentProxy):
-    '''scheduler proxy'''
-    name = 'scheduler'
-    methods = ['AddReservation', 'DelReservation', 'GetPartition', 'AddPartition', 'DelPartition', 'Set']
-
-class bcfg2(ComponentProxy):
-    '''bcfg2 client code'''
-    name = 'bcfg2'
-    methods = ['AssertProfile', 'GetConfig', 'GetProbes', 'RecvProbeData', 'RecvStats']
-
-class CommDict(dict):
-    '''CommDict is a dictionary that automatically instantiates a component proxy upon access'''
-    commnames = {'pm':process_manager, 'fs':file_stager, 'am':allocation_manager,
-                 'sched':scheduler, 'qm':queue_manager}
-
-    def __getitem__(self, name):
-        if not self.has_key(name):
-            self.__setitem__(name, self.commnames[name]())
-        return dict.__getitem__(self, name)
diff --git a/src/lib/Client/__init__.py b/src/lib/Client/__init__.py
index cc8a25964..7bcef1361 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__ = ["Frame", "Proxy", "Tools", "XML"]
+__all__ = ["Frame", "Tools", "XML"]
diff --git a/src/lib/Proxy.py b/src/lib/Proxy.py
new file mode 100644
index 000000000..5bcc78ad1
--- /dev/null
+++ b/src/lib/Proxy.py
@@ -0,0 +1,188 @@
+"""RPC client access to cobalt components.
+
+Classes:
+ComponentProxy -- an RPC client proxy to Cobalt components
+
+Functions:
+load_config -- read configuration files
+"""
+
+__revision__ = '$Revision: $'
+
+from ConfigParser import SafeConfigParser, NoSectionError
+import logging, socket, urlparse, time, Bcfg2.tlslite.errors
+from Bcfg2.tlslite.integration.XMLRPCTransport import XMLRPCTransport
+import xmlrpclib
+from xmlrpclib import _Method
+
+__all__ = [
+    "ComponentProxy", "ComponentLookupError", "RetryMethod", 
+    "register_component", "find_configured_servers",
+]
+
+local_components = dict()
+known_servers = dict()
+
+def register_component (component):
+    local_components[component.name] = component
+
+
+class ComponentError (Exception):
+    
+    """Component error baseclass"""
+
+
+class ComponentLookupError (ComponentError):
+
+    """Unable to locate an address for the given component."""
+
+
+class ComponentOperationError (ComponentError):
+    
+    """Component Failure during operation"""
+
+
+class RetryMethod(_Method):
+    """Method with error handling and retries built in"""
+    log = logging.getLogger('xmlrpc')
+    def __call__(self, *args):
+        max_retries = 4
+        for retry in range(max_retries):
+            try:
+                return _Method.__call__(self, *args)
+            except xmlrpclib.ProtocolError:
+                self.log.error("Server failure: Protocol Error")
+                raise xmlrpclib.Fault(20, "Server Failure")
+            except socket.error:
+                pass
+            except Bcfg2.tlslite.errors.TLSFingerprintError, err:
+                self.log.error("Server fingerprint did not match")
+                errmsg = err.message.split()
+                self.log.error("Got %s expected %s" % (errmsg[3], errmsg[4]))
+                raise SystemExit, 1
+            except:
+                self.log.error("Unknown failure", exc_info=1)
+                break
+            time.sleep(0.5)
+        raise xmlrpclib.Fault(20, "Server Failure")
+
+# sorry jon
+xmlrpclib._Method = RetryMethod
+
+def ComponentProxy (component_name, defer=False, user=None, password=None,
+                    fingerprint=None):
+    
+    """Constructs proxies to components.
+    
+    Arguments:
+    component_name -- name of the component to connect to
+    
+    Additional arguments are passed to the ServerProxy constructor.
+    """
+    
+    if defer:
+        return DeferredProxy(component_name)
+    
+    if component_name in local_components:
+        return LocalProxy(local_components[component_name])
+    elif component_name in known_servers:
+        url = known_servers[component_name]
+    elif component_name != "service-location":
+        try:
+            slp = ComponentProxy("service-location")
+        except ComponentLookupError:
+            raise ComponentLookupError(component_name)
+        try:
+            url = slp.locate(component_name)
+        except:
+            raise ComponentLookupError(component_name)
+        if not url:
+            raise ComponentLookupError(component_name)
+    else:
+        raise ComponentLookupError(component_name)
+    # process url
+    if user and password:
+        method, path = urlparse.urlparse(url)[:2]
+        newurl = "%s://%s:%s@%s" % (method, user, password, path)
+    else:
+        newurl = url
+    return xmlrpclib.ServerProxy(newurl, allow_none=True,
+                                 transport=XMLRPCTransport(x509Fingerprint=fingerprint))
+
+class LocalProxy (object):
+    
+    """Proxy-like filter for inter-component communication.
+    
+    Used to access other components stored in local memory,
+    without having to transport across tcp/http.
+    
+    Dispatches method calls through the component's _dispatch
+    method to keep the interface between this and ServerProxy
+    consistent.
+    """
+    
+    def __init__ (self, component):
+        self._component = component
+    
+    def __getattr__ (self, attribute):
+        return LocalProxyMethod(self, attribute)
+
+
+class LocalProxyMethod (object):
+    
+    def __init__ (self, proxy, func_name):
+        self._proxy = proxy
+        self._func_name = func_name
+    
+    def __call__ (self, *args):
+        return self._proxy._component._dispatch(self._func_name, args)
+
+
+class DeferredProxy (object):
+    
+    """Defering proxy object.
+    
+    Gets a new proxy when it can't connect to a component.
+    """
+    
+    def __init__ (self, component_name):
+        self._component_name = component_name
+    
+    def __getattr__ (self, attribute):
+        return DeferredProxyMethod(self, attribute)
+
+
+class DeferredProxyMethod (object):
+    
+    def __init__ (self, proxy, func_name):
+        self._proxy = proxy
+        self._func_name = func_name
+    
+    def __call__ (self, *args):
+        proxy = ComponentProxy(self._proxy._component_name, defer=False)
+        func = getattr(proxy, self._func_name)
+        return func(*args)
+
+
+def find_configured_servers (config_files=None):
+    """Read associated config files into the module.
+    
+    Arguments:
+    config_files -- a list of paths to config files.
+    """
+    if not config_files:
+        config_files = ['/etc/bcfg2.conf']
+    config = SafeConfigParser()
+    config.read(config_files)
+    try:
+        components = config.options("components")
+    except NoSectionError:
+        return []
+    known_servers.clear()
+    known_servers.update(dict([
+        (component, config.get("components", component))
+        for component in components
+    ]))
+    return known_servers.copy()
+
+find_configured_servers()
diff --git a/src/lib/__init__.py b/src/lib/__init__.py
index 7e9e8a92a..7f771da6f 100644
--- a/src/lib/__init__.py
+++ b/src/lib/__init__.py
@@ -1,4 +1,4 @@
 '''base modules definition'''
 __revision__ = '$Revision$'
 
-__all__ = ['Server', 'Client', 'Component', 'Logging', 'Options']
+__all__ = ['Server', 'Client', 'Component', 'Logging', 'Options', 'Proxy']
diff --git a/src/lib/tlslite/integration/HTTPTLSConnection.py b/src/lib/tlslite/integration/HTTPTLSConnection.py
index a20400893..a50c053c7 100755
--- a/src/lib/tlslite/integration/HTTPTLSConnection.py
+++ b/src/lib/tlslite/integration/HTTPTLSConnection.py
@@ -22,7 +22,7 @@ class HTTPBaseTLSConnection(httplib.HTTPConnection):
     def connect(self):
         sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
         if hasattr(sock, 'settimeout'):
-            sock.settimeout(10)
+            sock.settimeout(90)
         sock.connect((self.host, self.port))
 
         #Use a TLSConnection to emulate a socket