def reload_config_info(self):
"""
Refresh the configuration values.
Reload the configuration, get configuration values from self.cfg
and set them as attributes of self.
To be called at least once.
"""
# TODO: merge this method into the constructor, there is no reason to
# keep it separated anymore.
self.cfg.load()
self.client_id = self.cfg.get('User', 'client_id')
self.username = self.cfg.get('User', 'username')
self.priv_key = self.cfg.get('Application Paths',
'client_priv_key_file')
self.host = self.cfg.get('System', 'server_hostname')
self.port = self.cfg.getint('System', 'server_port')
self.server_certificate = self.cfg.get('Application Paths',
'server_certificate')
self.storage_hostname = self.cfg.get('System', 'storage_endpoint')
self.refused_declare_max = self.cfg.getint('System',
'refused_declare_max')
self.refused_declare_waiting_time = self.cfg.getint(
'System', 'refused_declare_waiting_time')
self.commit_threshold_seconds = self.cfg.getint(
'Client', 'commit_threshold_seconds')
self.commit_threshold_operations = self.cfg.getint(
'Client', 'commit_threshold_operations')
self.commit_threshold_bytes = self.cfg.getint(
'Client', 'commit_threshold_bytes')
temp = self.cfg.get('Application Paths', 'transaction_cache_db')
self.transaction_cache = TransactionCache(temp)
self.integrity_manager = IntegrityManager(None)
is_firt_startup = self._internal_facade.is_first_startup()
self.cryptoAdapter = Adapter(self.cfg,
self.warebox,
self._input_queue,
self._lockfile_fd,
enc_dir='enc',
first_startup=is_firt_startup)
self.worker_pool = WorkerPool(self.warebox, self, self.cfg,
self.cryptoAdapter)
self.temp_dir = self.cryptoAdapter.get_enc_dir()
self._ui_controller.update_config_info(self.cfg)
def reload_config_info(self):
"""
Refresh the configuration values.
Reload the configuration, get configuration values from self.cfg
and set them as attributes of self.
To be called at least once.
"""
# TODO: merge this method into the constructor, there is no reason to
# keep it separated anymore.
self.cfg.load()
self.client_id = self.cfg.get('User', 'client_id')
self.username = self.cfg.get('User', 'username')
self.priv_key = self.cfg.get('Application Paths', 'client_priv_key_file')
self.host = self.cfg.get('System', 'server_hostname')
self.port = self.cfg.getint('System', 'server_port')
self.server_certificate = self.cfg.get('Application Paths', 'server_certificate')
self.storage_hostname = self.cfg.get('System', 'storage_endpoint')
self.refused_declare_max = self.cfg.getint(
'System', 'refused_declare_max')
self.refused_declare_waiting_time = self.cfg.getint(
'System', 'refused_declare_waiting_time')
self.commit_threshold_seconds = self.cfg.getint(
'Client', 'commit_threshold_seconds')
self.commit_threshold_operations = self.cfg.getint(
'Client', 'commit_threshold_operations')
self.commit_threshold_bytes = self.cfg.getint(
'Client', 'commit_threshold_bytes')
temp = self.cfg.get('Application Paths', 'transaction_cache_db')
self.transaction_cache = TransactionCache(temp)
self.integrity_manager = IntegrityManager(None)
is_firt_startup = self._internal_facade.is_first_startup()
self.cryptoAdapter = Adapter(self.cfg,
self.warebox,
self._input_queue,
self._lockfile_fd,
enc_dir='enc',
first_startup=is_firt_startup)
self.worker_pool = WorkerPool(self.warebox,
self,
self.cfg,
self.cryptoAdapter)
self.temp_dir = self.cryptoAdapter.get_enc_dir()
self._ui_controller.update_config_info(self.cfg)
class ServerSession(threading.Thread):
"""
The thread that controls the communication with the server and the
internal execution of the client.
ServerSession is the intelligent part of the client application. It
is implemented as an event-loop machine, receiving events from many
sources: the user, ServerSession itself, other application
components and the server, each with a different priority level. It
decides, for example, when to handle operations for synchronizing
data and when to answer to messages from the server, thus
implementing the communication protocol.
The logic is implemented as an object-oriented state machine, which
decides which events to handle in each state and how to do it.
ServerSession is both a container (formally a "context") for "state"
objects and the only public interface of this component. The context
gives the states a shared memory space and access to other
components.
All the logic is actually implemented in the state objects, limiting
ServerSession to execute the "current state". State objects also
decide when to switch to another state, as a reaction to an input
event. The states are implemented using object-oriented inheritance
in order to common factor the logic of several states, making
ServerSession precisely a "Hierarchical State Machine".
See the "State" design pattern from the book: Gamma et al, "Design
Patterns: Elements of Reusable Object-Oriented Software" for a
reference to the design.
"""
def __init__(self,
cfg, warebox, storage_cache,
startup_synchronization, filesystem_watcher, linker,
metadata_db, hashes_db, internal_facade, ui_controller,
lockfile_fd, auto_start, input_queue, scheduler):
"""
@param cfg:
Instance of filerockclient.config.ConfigManager.
@param warebox:
Instance of filerockclient.warebox.Warebox.
@param storage_cache:
Instance of filerockclient.databases.storage_cache.
StorageCache.
@param startup_synchronization:
Instance of filerockclient.serversession.
startup_synchronization.
@param filesystem_watcher:
Instance of any class in the filerockclient.
filesystem_watcher package.
@param linker:
Instance of filerockclient.linker.Linker.
@param metadata_db:
Instance of filerockclient.databases.metadata.
MetadataDB.
@param hashes_db:
Instance of filerockclient.databases.hashes.HashesDB.
@param internal_facade:
Instance of filerockclient.internal_facade.
InternalFacade.
@param ui_controller:
Instance of filerockclient.ui.ui_controller.
UIController.
@param lockfile_fd:
File descriptor of the lock file which ensures there
is only one instance of FileRock Client running.
Child processes have to close it to avoid stale locks.
@param auto_start:
Boolean flag telling whether ServerSession should
connect to the server when started.
@param input_queue:
Instance of filerockclient.util.multi_queue.
MultiQueue. It is expected to have the following
queues:
usercommand: Commands sent by the user
sessioncommand: ServerSession internal use commands
systemcommand: Commands sent by other client components
servermessage: Messages sent by the server.
operation: PathnameOperation objects to handle
@param scheduler:
Instance of filerockclient.util.scheduler.Scheduler.
"""
threading.Thread.__init__(self, name=self.__class__.__name__)
self.logger = logging.getLogger("FR.%s" % self.__class__.__name__)
self._input_queue = input_queue
self.warebox = warebox
self.startup_synchronization = startup_synchronization
self.filesystem_watcher = filesystem_watcher
self._internal_facade = internal_facade
self._ui_controller = ui_controller
self.metadataDB = metadata_db
self.hashesDB = hashes_db
self.auto_start = auto_start
self._scheduler = scheduler
self.storage_cache = storage_cache
self.linker = linker
self.warebox = warebox
self.cfg = cfg
self._lockfile_fd = lockfile_fd
self._started = False
self.must_die = threading.Event()
# TODO: this flag exists due to auto-disconnection. It will be removed
# and replaced by a CONNECTFORCE command as soon as ServerSession will
# stop going automatically to DisconnectedState.
self.disconnect_other_client = False
self.operation_responses = {}
self._pathname2id = {}
self.output_message_queue = Queue.Queue()
self.input_keepalive_queue = Queue.Queue()
self.current_state = None
self.reconnection_time = 1
self.num_connection_attempts = 0
self.max_connection_attempts = MAX_CONNECTION_ATTEMPTS
self._basis_lock = threading.Lock()
self.server_basis = None
self.session_id = None
self.storage_ip_address = None
self.refused_declare_count = 0
self._current_basis = None
self.id = 0
self._sync_operations = []
self.keepalive_timer = ConnectionLifeKeeper(
self._input_queue, self.input_keepalive_queue,
self.output_message_queue, True)
self.transaction = Transaction()
self.transaction_manager = TransactionManager(
self.transaction, self.storage_cache)
StateRegister.setup(self)
self.client_id = None
self.username = None
self.priv_key = None
self.host = None
self.port = None
self.server_certificate = None
self.storage_hostname = None
self.refused_declare_max = None
self.refused_declare_waiting_time = None
self.commit_threshold_seconds = None
self.commit_threshold_operations = None
self.commit_threshold_bytes = None
self.transaction_cache = None
self.integrity_manager = None
self.cryptoAdapter = None
self.temp_dir = None
self.connection_reader = None
self.connection_writer = None
self.sock = None
self.listening_operations = False
self.reload_config_info()
def reload_config_info(self):
"""
Refresh the configuration values.
Reload the configuration, get configuration values from self.cfg
and set them as attributes of self.
To be called at least once.
"""
# TODO: merge this method into the constructor, there is no reason to
# keep it separated anymore.
self.cfg.load()
self.client_id = self.cfg.get('User', 'client_id')
self.username = self.cfg.get('User', 'username')
self.priv_key = self.cfg.get('Application Paths', 'client_priv_key_file')
self.host = self.cfg.get('System', 'server_hostname')
self.port = self.cfg.getint('System', 'server_port')
self.server_certificate = self.cfg.get('Application Paths', 'server_certificate')
self.storage_hostname = self.cfg.get('System', 'storage_endpoint')
self.refused_declare_max = self.cfg.getint(
'System', 'refused_declare_max')
self.refused_declare_waiting_time = self.cfg.getint(
'System', 'refused_declare_waiting_time')
self.commit_threshold_seconds = self.cfg.getint(
'Client', 'commit_threshold_seconds')
self.commit_threshold_operations = self.cfg.getint(
'Client', 'commit_threshold_operations')
self.commit_threshold_bytes = self.cfg.getint(
'Client', 'commit_threshold_bytes')
temp = self.cfg.get('Application Paths', 'transaction_cache_db')
self.transaction_cache = TransactionCache(temp)
self.integrity_manager = IntegrityManager(None)
is_firt_startup = self._internal_facade.is_first_startup()
self.cryptoAdapter = Adapter(self.cfg,
self.warebox,
self._input_queue,
self._lockfile_fd,
enc_dir='enc',
first_startup=is_firt_startup)
self.worker_pool = WorkerPool(self.warebox,
self,
self.cfg,
self.cryptoAdapter)
self.temp_dir = self.cryptoAdapter.get_enc_dir()
self._ui_controller.update_config_info(self.cfg)
def run(self):
"""Implementation of the threading.Thread.run() method."""
self._started = True
try:
self.worker_pool.start_workers()
self.keepalive_timer.start()
self.current_state = StateRegister.get('DisconnectedState')
curr_basis = self.current_state._load_trusted_basis()
self.integrity_manager.setCurrentBasis(curr_basis)
self.logger.info(u'Current basis is: %s' % curr_basis)
self.current_state._on_entering()
self._internal_facade.set_global_status(GStatuses.NC_STOPPED)
if self.auto_start:
self._input_queue.put(Command('CONNECT'), 'sessioncommand')
self.cryptoAdapter.start()
self._scheduler.schedule_action(
self.check_encrypted_folder, name='check_encrypted_folder',
seconds=5, repeating=True)
# The event loop
self._main_loop()
except UnexpectedMessageException as e:
self.logger.critical(
u"Received an unexpected message from the Server while in "
u"state '%s': %s. Forcing termination."
% (self.current_state.__class__, str(e)))
raise
except ProtocolException as e:
self.logger.critical(
u"Detected an unrecoverable error, forcing termination: %s"
% str(e))
# Pre-emptive release, just stop before messing up the server
self.release_network_resources()
raise
except Exception as e:
self.logger.critical(
u"Forcing termination due to uncaught exception '%s': %s"
% (e.__class__, e))
self.logger.debug(
u"Last error stacktrace:\n%s" % traceback.format_exc())
# Pre-emptive release, just stop before messing up the server
self.release_network_resources()
raise
def _main_loop(self):
"""
The event loop.
A loop that contiuosly calls the current state of the state
machine, executing its logic.
It exits when self.terminate() is called.
"""
while not self.must_die.is_set():
next_state = self.current_state.do_execute()
if next_state != self.current_state:
self.current_state._on_leaving()
next_state._on_entering()
self.current_state = next_state
def check_encrypted_folder(self):
"""
Check if encryption preconditions are satisfied, try to
satisfy them otherwise.
This method is meant to be asynchronously called by a timer,
precisely to be registered into self._scheduler.
"""
if not self.cryptoAdapter.check_precondition(self._ui_controller):
self._internal_facade.terminate()
def acquire_network_resources(self):
"""
Configure a network connection to the server.
The resulting socket is handled by two instances of
ServerConnectionReader and ServerConnectionWriter, which are
created and run as well. It is possibile to send/receive
message to/from them through the queues self.output_message_queue
and self._input_queue (servermessage).
Note: this private method should be actually "protected" for
the ServerSession states, but Python doesn't have such a
protection level.
"""
try:
self.logger.debug(u"Creating a socket on %s:%s", self.host, self.port)
sock = socket.create_connection((self.host, self.port), timeout=10)
ca_chain = os.path.abspath(self.server_certificate)
self.sock = ssl.wrap_socket(
sock, cert_reqs=ssl.CERT_REQUIRED, ca_certs=ca_chain,
ssl_version=ssl.PROTOCOL_TLSv1)
self.sock.setblocking(True)
match_hostname(self.sock.getpeercert(), self.host)
except CertificateError as e:
self.logger.critical(u"SSL certificate validation failed: %s" % e)
raise ssl.SSLError(e)
except socket.error as exception:
self.logger.debug(u"Error opening SSL socket: %s" % exception)
self.logger.warning(
u"Unable to connect, re-trying in %s seconds."
% self.reconnection_time)
self.reconnection_time = stoppable_exponential_backoff_waiting(
self.reconnection_time, self.must_die, 10)
self.num_connection_attempts += 1
return False
except socket.timeout as exception:
self.logger.debug(u"Socket timeout: %s" % exception)
self.logger.warning(u"Unable to connect, re-trying in %s seconds."
% self.reconnection_time)
self.reconnection_time = stoppable_exponential_backoff_waiting(
self.reconnection_time, self.must_die, 10)
self.num_connection_attempts += 1
return False
self.connection_reader = ServerConnectionReader(
self._input_queue, self.input_keepalive_queue, self.sock)
self.connection_writer = ServerConnectionWriter(
self._input_queue, self.output_message_queue, self.sock)
self.connection_reader.start()
self.connection_writer.start()
self.reconnection_time = 1
return True
def release_network_resources(self):
"""
Close the active connection to the server, if any.
Note: this private method should be actually "protected" for
the ServerSession states, but Python doesn't have such a
protection level.
"""
try:
self.connection_reader.terminate()
except AttributeError:
pass
try:
self.connection_writer.terminate()
except AttributeError:
pass
try:
self.sock.shutdown(socket.SHUT_RDWR)
self.sock.close()
except socket.error:
# Shutdown yelds an error on already closed sockets
pass
except AttributeError:
pass
def commit(self):
"""Make the client commit the current transaction."""
self._input_queue.put(Command('USERCOMMIT'), 'usercommand')
def connect(self):
"""Make the client connect to the server."""
self._input_queue.put(Command('CONNECT'), 'usercommand')
def disconnect(self):
"""Make the client disconnect from the client, if connected."""
# TODO: this method has been temporarly replaced by PAUSE
self._input_queue.put(Command('DISCONNECT'), 'usercommand')
def signal_free_worker(self):
"""
Tell ServerSession that a worker is free to receive new tasks.
This method is meant to be called by WorkerPool.
"""
self._input_queue.put(Command('WORKERFREE'), 'systemcommand')
def signal_download_integrity_error(
self, operation, reason,
expected_etag, expected_basis,
actual_etag, computed_basis):
"""Tell ServerSession that the integrity check of a downloaded
file has failed.
This method is meant to be called by Workers.
@param operation:
Instance of PathnameOperation. Remember that it
contains also its Proof object.
@param reason:
String shortly describing the error.
@param expected_etag:
The etag the file was expected to have. It's the one
communicated by the server in its file list.
@param expected_basis:
The trusted basis. It's the one the user had
accepted when the sync started.
@param actual_etag:
The etag the file has turned to have after being
downloaded.
@param computed_basis:
The basis returned by the IntegrityManager when
computing the given proof object. Possibly None.
"""
cmd = Command('INTEGRITYERRORONDOWNLOAD')
cmd.operation = operation
cmd.proof = operation.download_info['proof']
cmd.reason = reason
cmd.expected_etag = expected_etag
cmd.expected_basis = expected_basis
cmd.actual_etag = actual_etag
cmd.computed_basis = computed_basis
self._input_queue.put(cmd, 'systemcommand')
def signal_deletelocal_integrity_error(
self, pathname, proof, reason, expected_basis, computed_basis):
"""Tell ServerSession that the integrity check of a
pathname to delete locally has failed.
This method is meant to be called by Workers.
@param pathname:
String representing the pathname.
@param reason:
String shortly describing the error.
@param expected_basis:
The trusted basis. It's the one the user had
accepted when the sync started.
@param computed_basis:
The basis returned by the IntegrityManager when
computing the given proof object. Possibly None.
"""
cmd = Command('INTEGRITYERRORONDELETELOCAL')
cmd.pathname = pathname
cmd.proof = proof
cmd.reason = reason
cmd.expected_basis = expected_basis
cmd.computed_basis = computed_basis
self._input_queue.put(cmd, 'systemcommand')
def get_current_basis(self):
"""
Return the current trusted basis.
@return The current trusted basis.
"""
with self._basis_lock:
return self._current_basis
def print_transaction(self):
"""
Print the list of operations in the current transaction.
Debug method, it prints to stdout and thus works only when the
application is attached to a console.
"""
self.transaction.print_all()
def terminate(self):
"""
Termination routine for this component.
Stops the running thread and releases any acquired resource.
"""
self.logger.debug(u"Terminating Server Session...")
if self._started:
self.must_die.set()
self.worker_pool.terminate()
self._input_queue.put(Command('TERMINATE'), 'usercommand')
self.transaction.can_be_committed.set()
self.join() if self is not threading.current_thread() else None
self.keepalive_timer.terminate()
self.release_network_resources()
self.cryptoAdapter.terminate()
self.logger.debug(u"Server Session terminanted.")
class ServerSession(threading.Thread):
"""
The thread that controls the communication with the server and the
internal execution of the client.
ServerSession is the intelligent part of the client application. It
is implemented as an event-loop machine, receiving events from many
sources: the user, ServerSession itself, other application
components and the server, each with a different priority level. It
decides, for example, when to handle operations for synchronizing
data and when to answer to messages from the server, thus
implementing the communication protocol.
The logic is implemented as an object-oriented state machine, which
decides which events to handle in each state and how to do it.
ServerSession is both a container (formally a "context") for "state"
objects and the only public interface of this component. The context
gives the states a shared memory space and access to other
components.
All the logic is actually implemented in the state objects, limiting
ServerSession to execute the "current state". State objects also
decide when to switch to another state, as a reaction to an input
event. The states are implemented using object-oriented inheritance
in order to common factor the logic of several states, making
ServerSession precisely a "Hierarchical State Machine".
See the "State" design pattern from the book: Gamma et al, "Design
Patterns: Elements of Reusable Object-Oriented Software" for a
reference to the design.
"""
def __init__(self, cfg, warebox, storage_cache, startup_synchronization,
filesystem_watcher, linker, metadata_db, hashes_db,
internal_facade, ui_controller, lockfile_fd, auto_start,
input_queue, scheduler):
"""
@param cfg:
Instance of filerockclient.config.ConfigManager.
@param warebox:
Instance of filerockclient.warebox.Warebox.
@param storage_cache:
Instance of filerockclient.databases.storage_cache.
StorageCache.
@param startup_synchronization:
Instance of filerockclient.serversession.
startup_synchronization.
@param filesystem_watcher:
Instance of any class in the filerockclient.
filesystem_watcher package.
@param linker:
Instance of filerockclient.linker.Linker.
@param metadata_db:
Instance of filerockclient.databases.metadata.
MetadataDB.
@param hashes_db:
Instance of filerockclient.databases.hashes.HashesDB.
@param internal_facade:
Instance of filerockclient.internal_facade.
InternalFacade.
@param ui_controller:
Instance of filerockclient.ui.ui_controller.
UIController.
@param lockfile_fd:
File descriptor of the lock file which ensures there
is only one instance of FileRock Client running.
Child processes have to close it to avoid stale locks.
@param auto_start:
Boolean flag telling whether ServerSession should
connect to the server when started.
@param input_queue:
Instance of filerockclient.util.multi_queue.
MultiQueue. It is expected to have the following
queues:
usercommand: Commands sent by the user
sessioncommand: ServerSession internal use commands
systemcommand: Commands sent by other client components
servermessage: Messages sent by the server.
operation: PathnameOperation objects to handle
@param scheduler:
Instance of filerockclient.util.scheduler.Scheduler.
"""
threading.Thread.__init__(self, name=self.__class__.__name__)
self.logger = logging.getLogger("FR.%s" % self.__class__.__name__)
self._input_queue = input_queue
self.warebox = warebox
self.startup_synchronization = startup_synchronization
self.filesystem_watcher = filesystem_watcher
self._internal_facade = internal_facade
self._ui_controller = ui_controller
self.metadataDB = metadata_db
self.hashesDB = hashes_db
self.auto_start = auto_start
self._scheduler = scheduler
self.storage_cache = storage_cache
self.linker = linker
self.warebox = warebox
self.cfg = cfg
self._lockfile_fd = lockfile_fd
self._started = False
self.must_die = threading.Event()
# TODO: this flag exists due to auto-disconnection. It will be removed
# and replaced by a CONNECTFORCE command as soon as ServerSession will
# stop going automatically to DisconnectedState.
self.disconnect_other_client = False
self.operation_responses = {}
self._pathname2id = {}
self.output_message_queue = Queue.Queue()
self.input_keepalive_queue = Queue.Queue()
self.current_state = None
self.reconnection_time = 1
self.num_connection_attempts = 0
self.max_connection_attempts = MAX_CONNECTION_ATTEMPTS
self._basis_lock = threading.Lock()
self.server_basis = None
self.session_id = None
self.storage_ip_address = None
self.refused_declare_count = 0
self._current_basis = None
self.id = 0
self._sync_operations = []
self.keepalive_timer = ConnectionLifeKeeper(self._input_queue,
self.input_keepalive_queue,
self.output_message_queue,
True)
self.transaction = Transaction()
self.transaction_manager = TransactionManager(self.transaction,
self.storage_cache)
StateRegister.setup(self)
self.client_id = None
self.username = None
self.priv_key = None
self.host = None
self.port = None
self.server_certificate = None
self.storage_hostname = None
self.refused_declare_max = None
self.refused_declare_waiting_time = None
self.commit_threshold_seconds = None
self.commit_threshold_operations = None
self.commit_threshold_bytes = None
self.transaction_cache = None
self.integrity_manager = None
self.cryptoAdapter = None
self.temp_dir = None
self.connection_reader = None
self.connection_writer = None
self.sock = None
self.listening_operations = False
self.reload_config_info()
def reload_config_info(self):
"""
Refresh the configuration values.
Reload the configuration, get configuration values from self.cfg
and set them as attributes of self.
To be called at least once.
"""
# TODO: merge this method into the constructor, there is no reason to
# keep it separated anymore.
self.cfg.load()
self.client_id = self.cfg.get('User', 'client_id')
self.username = self.cfg.get('User', 'username')
self.priv_key = self.cfg.get('Application Paths',
'client_priv_key_file')
self.host = self.cfg.get('System', 'server_hostname')
self.port = self.cfg.getint('System', 'server_port')
self.server_certificate = self.cfg.get('Application Paths',
'server_certificate')
self.storage_hostname = self.cfg.get('System', 'storage_endpoint')
self.refused_declare_max = self.cfg.getint('System',
'refused_declare_max')
self.refused_declare_waiting_time = self.cfg.getint(
'System', 'refused_declare_waiting_time')
self.commit_threshold_seconds = self.cfg.getint(
'Client', 'commit_threshold_seconds')
self.commit_threshold_operations = self.cfg.getint(
'Client', 'commit_threshold_operations')
self.commit_threshold_bytes = self.cfg.getint(
'Client', 'commit_threshold_bytes')
temp = self.cfg.get('Application Paths', 'transaction_cache_db')
self.transaction_cache = TransactionCache(temp)
self.integrity_manager = IntegrityManager(None)
is_firt_startup = self._internal_facade.is_first_startup()
self.cryptoAdapter = Adapter(self.cfg,
self.warebox,
self._input_queue,
self._lockfile_fd,
enc_dir='enc',
first_startup=is_firt_startup)
self.worker_pool = WorkerPool(self.warebox, self, self.cfg,
self.cryptoAdapter)
self.temp_dir = self.cryptoAdapter.get_enc_dir()
self._ui_controller.update_config_info(self.cfg)
def run(self):
"""Implementation of the threading.Thread.run() method."""
self._started = True
try:
self.worker_pool.start_workers()
self.keepalive_timer.start()
self.current_state = StateRegister.get('DisconnectedState')
curr_basis = self.current_state._load_trusted_basis()
self.integrity_manager.setCurrentBasis(curr_basis)
self.logger.info(u'Current basis is: %s' % curr_basis)
self.current_state._on_entering()
self._internal_facade.set_global_status(GStatuses.NC_STOPPED)
if self.auto_start:
self._input_queue.put(Command('CONNECT'), 'sessioncommand')
self.cryptoAdapter.start()
self._scheduler.schedule_action(self.check_encrypted_folder,
name='check_encrypted_folder',
seconds=5,
repeating=True)
# The event loop
self._main_loop()
except UnexpectedMessageException as e:
self.logger.critical(
u"Received an unexpected message from the Server while in "
u"state '%s': %s. Forcing termination." %
(self.current_state.__class__, str(e)))
raise
except ProtocolException as e:
self.logger.critical(
u"Detected an unrecoverable error, forcing termination: %s" %
str(e))
# Pre-emptive release, just stop before messing up the server
self.release_network_resources()
raise
except Exception as e:
self.logger.critical(
u"Forcing termination due to uncaught exception '%s': %s" %
(e.__class__, e))
self.logger.debug(u"Last error stacktrace:\n%s" %
traceback.format_exc())
# Pre-emptive release, just stop before messing up the server
self.release_network_resources()
raise
def _main_loop(self):
"""
The event loop.
A loop that contiuosly calls the current state of the state
machine, executing its logic.
It exits when self.terminate() is called.
"""
while not self.must_die.is_set():
next_state = self.current_state.do_execute()
if next_state != self.current_state:
self.current_state._on_leaving()
next_state._on_entering()
self.current_state = next_state
def check_encrypted_folder(self):
"""
Check if encryption preconditions are satisfied, try to
satisfy them otherwise.
This method is meant to be asynchronously called by a timer,
precisely to be registered into self._scheduler.
"""
if not self.cryptoAdapter.check_precondition(self._ui_controller):
self._internal_facade.terminate()
def acquire_network_resources(self):
"""
Configure a network connection to the server.
The resulting socket is handled by two instances of
ServerConnectionReader and ServerConnectionWriter, which are
created and run as well. It is possibile to send/receive
message to/from them through the queues self.output_message_queue
and self._input_queue (servermessage).
Note: this private method should be actually "protected" for
the ServerSession states, but Python doesn't have such a
protection level.
"""
try:
self.logger.debug(u"Creating a socket on %s:%s", self.host,
self.port)
sock = socket.create_connection((self.host, self.port), timeout=10)
ca_chain = os.path.abspath(self.server_certificate)
self.sock = ssl.wrap_socket(sock,
cert_reqs=ssl.CERT_REQUIRED,
ca_certs=ca_chain,
ssl_version=ssl.PROTOCOL_TLSv1)
self.sock.setblocking(True)
match_hostname(self.sock.getpeercert(), self.host)
except CertificateError as e:
self.logger.critical(u"SSL certificate validation failed: %s" % e)
raise ssl.SSLError(e)
except socket.error as exception:
self.logger.debug(u"Error opening SSL socket: %s" % exception)
self.logger.warning(
u"Unable to connect, re-trying in %s seconds." %
self.reconnection_time)
self.reconnection_time = stoppable_exponential_backoff_waiting(
self.reconnection_time, self.must_die, 10)
self.num_connection_attempts += 1
return False
except socket.timeout as exception:
self.logger.debug(u"Socket timeout: %s" % exception)
self.logger.warning(
u"Unable to connect, re-trying in %s seconds." %
self.reconnection_time)
self.reconnection_time = stoppable_exponential_backoff_waiting(
self.reconnection_time, self.must_die, 10)
self.num_connection_attempts += 1
return False
self.connection_reader = ServerConnectionReader(
self._input_queue, self.input_keepalive_queue, self.sock)
self.connection_writer = ServerConnectionWriter(
self._input_queue, self.output_message_queue, self.sock)
self.connection_reader.start()
self.connection_writer.start()
self.reconnection_time = 1
return True
def release_network_resources(self):
"""
Close the active connection to the server, if any.
Note: this private method should be actually "protected" for
the ServerSession states, but Python doesn't have such a
protection level.
"""
try:
self.connection_reader.terminate()
except AttributeError:
pass
try:
self.connection_writer.terminate()
except AttributeError:
pass
try:
self.sock.shutdown(socket.SHUT_RDWR)
self.sock.close()
except socket.error:
# Shutdown yelds an error on already closed sockets
pass
except AttributeError:
pass
def commit(self):
"""Make the client commit the current transaction."""
self._input_queue.put(Command('USERCOMMIT'), 'usercommand')
def connect(self):
"""Make the client connect to the server."""
self._input_queue.put(Command('CONNECT'), 'usercommand')
def disconnect(self):
"""Make the client disconnect from the client, if connected."""
# TODO: this method has been temporarly replaced by PAUSE
self._input_queue.put(Command('DISCONNECT'), 'usercommand')
def signal_free_worker(self):
"""
Tell ServerSession that a worker is free to receive new tasks.
This method is meant to be called by WorkerPool.
"""
self._input_queue.put(Command('WORKERFREE'), 'systemcommand')
def signal_download_integrity_error(self, operation, reason, expected_etag,
expected_basis, actual_etag,
computed_basis):
"""Tell ServerSession that the integrity check of a downloaded
file has failed.
This method is meant to be called by Workers.
@param operation:
Instance of PathnameOperation. Remember that it
contains also its Proof object.
@param reason:
String shortly describing the error.
@param expected_etag:
The etag the file was expected to have. It's the one
communicated by the server in its file list.
@param expected_basis:
The trusted basis. It's the one the user had
accepted when the sync started.
@param actual_etag:
The etag the file has turned to have after being
downloaded.
@param computed_basis:
The basis returned by the IntegrityManager when
computing the given proof object. Possibly None.
"""
cmd = Command('INTEGRITYERRORONDOWNLOAD')
cmd.operation = operation
cmd.proof = operation.download_info['proof']
cmd.reason = reason
cmd.expected_etag = expected_etag
cmd.expected_basis = expected_basis
cmd.actual_etag = actual_etag
cmd.computed_basis = computed_basis
self._input_queue.put(cmd, 'systemcommand')
def signal_deletelocal_integrity_error(self, pathname, proof, reason,
expected_basis, computed_basis):
"""Tell ServerSession that the integrity check of a
pathname to delete locally has failed.
This method is meant to be called by Workers.
@param pathname:
String representing the pathname.
@param reason:
String shortly describing the error.
@param expected_basis:
The trusted basis. It's the one the user had
accepted when the sync started.
@param computed_basis:
The basis returned by the IntegrityManager when
computing the given proof object. Possibly None.
"""
cmd = Command('INTEGRITYERRORONDELETELOCAL')
cmd.pathname = pathname
cmd.proof = proof
cmd.reason = reason
cmd.expected_basis = expected_basis
cmd.computed_basis = computed_basis
self._input_queue.put(cmd, 'systemcommand')
def get_current_basis(self):
"""
Return the current trusted basis.
@return The current trusted basis.
"""
with self._basis_lock:
return self._current_basis
def print_transaction(self):
"""
Print the list of operations in the current transaction.
Debug method, it prints to stdout and thus works only when the
application is attached to a console.
"""
self.transaction.print_all()
def terminate(self):
"""
Termination routine for this component.
Stops the running thread and releases any acquired resource.
"""
self.logger.debug(u"Terminating Server Session...")
if self._started:
self.must_die.set()
self.worker_pool.terminate()
self._input_queue.put(Command('TERMINATE'), 'usercommand')
self.transaction.can_be_committed.set()
self.join() if self is not threading.current_thread() else None
self.keepalive_timer.terminate()
self.release_network_resources()
self.cryptoAdapter.terminate()
self.logger.debug(u"Server Session terminanted.")