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Packs a sub field s array into another array using a mask
def pack(array, sub_field_array, mask, inplace=False): """ Packs a sub field's array into another array using a mask Parameters: ---------- array : numpy.ndarray The array in which the sub field array will be packed into array_in : numpy.ndarray sub field array to pack mask : mask (ie: 0b00001111) Mask of the sub field inplace : {bool}, optional If true a new array is returned. (the default is False, which modifies the array in place) Raises ------ OverflowError If the values contained in the sub field array are greater than its mask's number of bits allows """ lsb = least_significant_bit(mask) max_value = int(mask >> lsb) if sub_field_array.max() > max_value: raise OverflowError( "value ({}) is greater than allowed (max: {})".format( sub_field_array.max(), max_value ) ) if inplace: array[:] = array & ~mask array[:] = array | ((sub_field_array << lsb) & mask).astype(array.dtype) else: array = array & ~mask return array | ((sub_field_array << lsb) & mask).astype(array.dtype)
Returns a list of the names of the dimensions that will be lost when converting from point_fmt_in to point_fmt_out
def lost_dimensions(point_fmt_in, point_fmt_out): """ Returns a list of the names of the dimensions that will be lost when converting from point_fmt_in to point_fmt_out """ unpacked_dims_in = PointFormat(point_fmt_in).dtype unpacked_dims_out = PointFormat(point_fmt_out).dtype out_dims = unpacked_dims_out.fields completely_lost = [] for dim_name in unpacked_dims_in.names: if dim_name not in out_dims: completely_lost.append(dim_name) return completely_lost
Returns the numpy. dtype used to store the point records in a numpy array
def dtype(self): """ Returns the numpy.dtype used to store the point records in a numpy array .. note:: The dtype corresponds to the dtype with sub_fields *packed* into their composed fields """ dtype = self._access_dict(dims.ALL_POINT_FORMATS_DTYPE, self.id) dtype = self._dtype_add_extra_dims(dtype) return dtype
Returns the numpy. dtype used to store the point records in a numpy array
def unpacked_dtype(self): """ Returns the numpy.dtype used to store the point records in a numpy array .. note:: The dtype corresponds to the dtype with sub_fields *unpacked* """ dtype = self._access_dict(dims.UNPACKED_POINT_FORMATS_DTYPES, self.id) dtype = self._dtype_add_extra_dims(dtype) return dtype
Returns a dict of the sub fields for this point format
def sub_fields(self): """ Returns a dict of the sub fields for this point format Returns ------- Dict[str, Tuple[str, SubField]] maps a sub field name to its composed dimension with additional information """ sub_fields_dict = {} for composed_dim_name, sub_fields in self.composed_fields.items(): for sub_field in sub_fields: sub_fields_dict[sub_field.name] = (composed_dim_name, sub_field) return sub_fields_dict
Returns the number of extra bytes
def num_extra_bytes(self): """ Returns the number of extra bytes """ return sum(np.dtype(extra_dim[1]).itemsize for extra_dim in self.extra_dims)
Returns True if the point format has waveform packet dimensions
def has_waveform_packet(self): """ Returns True if the point format has waveform packet dimensions """ dimensions = set(self.dimension_names) return all(name in dimensions for name in dims.WAVEFORM_FIELDS_NAMES)
Console script for satel_integra.
def main(port, ip, command, loglevel): """Console script for satel_integra.""" numeric_level = getattr(logging, loglevel.upper(), None) if not isinstance(numeric_level, int): raise ValueError('Invalid log level: %s' % loglevel) logging.basicConfig(level=numeric_level) click.echo("Demo of satel_integra library") if command == "demo": demo(ip, port)
Function to calculate checksum as per Satel manual.
def checksum(command): """Function to calculate checksum as per Satel manual.""" crc = 0x147A for b in command: # rotate (crc 1 bit left) crc = ((crc << 1) & 0xFFFF) | (crc & 0x8000) >> 15 crc = crc ^ 0xFFFF crc = (crc + (crc >> 8) + b) & 0xFFFF return crc
Debugging method to print out frames in hex.
def print_hex(data): """Debugging method to print out frames in hex.""" hex_msg = "" for c in data: hex_msg += "\\x" + format(c, "02x") _LOGGER.debug(hex_msg)
Verify checksum and strip header and footer of received frame.
def verify_and_strip(resp): """Verify checksum and strip header and footer of received frame.""" if resp[0:2] != b'\xFE\xFE': _LOGGER.error("Houston, we got problem:") print_hex(resp) raise Exception("Wrong header - got %X%X" % (resp[0], resp[1])) if resp[-2:] != b'\xFE\x0D': raise Exception("Wrong footer - got %X%X" % (resp[-2], resp[-1])) output = resp[2:-2].replace(b'\xFE\xF0', b'\xFE') c = checksum(bytearray(output[0:-2])) if (256 * output[-2:-1][0] + output[-1:][0]) != c: raise Exception("Wrong checksum - got %d expected %d" % ( (256 * output[-2:-1][0] + output[-1:][0]), c)) return output[0:-2]
Return list of positions of bits set to one in given data.
def list_set_bits(r, expected_length): """Return list of positions of bits set to one in given data. This method is used to read e.g. violated zones. They are marked by ones on respective bit positions - as per Satel manual. """ set_bit_numbers = [] bit_index = 0x1 assert (len(r) == expected_length + 1) for b in r[1:]: for i in range(8): if ((b >> i) & 1) == 1: set_bit_numbers.append(bit_index) bit_index += 1 return set_bit_numbers
Add header checksum and footer to command data.
def generate_query(command): """Add header, checksum and footer to command data.""" data = bytearray(command) c = checksum(data) data.append(c >> 8) data.append(c & 0xFF) data.replace(b'\xFE', b'\xFE\xF0') data = bytearray.fromhex("FEFE") + data + bytearray.fromhex("FE0D") return data
Basic demo of the monitoring capabilities.
def demo(host, port): """Basic demo of the monitoring capabilities.""" # logging.basicConfig(level=logging.DEBUG) loop = asyncio.get_event_loop() stl = AsyncSatel(host, port, loop, [1, 2, 3, 4, 5, 6, 7, 8, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30], [8, 9, 10] ) loop.run_until_complete(stl.connect()) loop.create_task(stl.arm("3333", 1)) loop.create_task(stl.disarm("3333")) loop.create_task(stl.keep_alive()) loop.create_task(stl.monitor_status()) loop.run_forever() loop.close()
Make a TCP connection to the alarm system.
async def connect(self): """Make a TCP connection to the alarm system.""" _LOGGER.debug("Connecting...") try: self._reader, self._writer = await asyncio.open_connection( self._host, self._port, loop=self._loop) _LOGGER.debug("sucess connecting...") except Exception as e: _LOGGER.warning( "Exception during connecting: %s.", e) self._writer = None self._reader = None return False return True
Start monitoring for interesting events.
async def start_monitoring(self): """Start monitoring for interesting events.""" data = generate_query( b'\x7F\x01\xDC\x99\x80\x00\x04\x00\x00\x00\x00\x00\x00') await self._send_data(data) resp = await self._read_data() if resp is None: _LOGGER.warning("Start monitoring - no data!") return if resp[1:2] != b'\xFF': _LOGGER.warning("Monitoring not accepted.")
0x17 outputs state 0x17 + 16/ 32 bytes
def _output_changed(self, msg): """0x17 outputs state 0x17 + 16/32 bytes""" status = {"outputs": {}} output_states = list_set_bits(msg, 32) self.violated_outputs = output_states _LOGGER.debug("Output states: %s, monitored outputs: %s", output_states, self._monitored_outputs) for output in self._monitored_outputs: status["outputs"][output] = \ 1 if output in output_states else 0 _LOGGER.debug("Returning status: %s", status) if self._output_changed_callback: self._output_changed_callback(status) return status
Send arming command to the alarm. Modes allowed: from 0 till 3.
async def arm(self, code, partition_list, mode=0): """Send arming command to the alarm. Modes allowed: from 0 till 3.""" _LOGGER.debug("Sending arm command, mode: %s!", mode) while len(code) < 16: code += 'F' code_bytes = bytearray.fromhex(code) mode_command = 0x80 + mode data = generate_query(mode_command.to_bytes(1, 'big') + code_bytes + partition_bytes(partition_list)) await self._send_data(data)
Send command to disarm.
async def disarm(self, code, partition_list): """Send command to disarm.""" _LOGGER.info("Sending disarm command.") while len(code) < 16: code += 'F' code_bytes = bytearray.fromhex(code) data = generate_query(b'\x84' + code_bytes + partition_bytes(partition_list)) await self._send_data(data)
Send command to clear the alarm.
async def clear_alarm(self, code, partition_list): """Send command to clear the alarm.""" _LOGGER.info("Sending clear the alarm command.") while len(code) < 16: code += 'F' code_bytes = bytearray.fromhex(code) data = generate_query(b'\x85' + code_bytes + partition_bytes(partition_list)) await self._send_data(data)
Send output turn on command to the alarm.
async def set_output(self, code, output_id, state): """Send output turn on command to the alarm.""" """0x88 outputs on + 8 bytes - user code + 16/32 bytes - output list If function is accepted, function result can be checked by observe the system state """ _LOGGER.debug("Turn on, output: %s, code: %s", output_id, code) while len(code) < 16: code += 'F' code_bytes = bytearray.fromhex(code) mode_command = 0x88 if state else 0x89 data = generate_query(mode_command.to_bytes(1, 'big') + code_bytes + output_bytes(output_id)) await self._send_data(data)
A workaround for Satel Integra disconnecting after 25s.
async def keep_alive(self): """A workaround for Satel Integra disconnecting after 25s. Every interval it sends some random question to the device, ignoring answer - just to keep connection alive. """ while True: await asyncio.sleep(self._keep_alive_timeout) if self.closed: return # Command to read status of the alarm data = generate_query(b'\xEE\x01\x01') await self._send_data(data)
Start monitoring of the alarm status.
async def monitor_status(self, alarm_status_callback=None, zone_changed_callback=None, output_changed_callback=None): """Start monitoring of the alarm status. Send command to satel integra to start sending updates. Read in a loop and call respective callbacks when received messages. """ self._alarm_status_callback = alarm_status_callback self._zone_changed_callback = zone_changed_callback self._output_changed_callback = output_changed_callback _LOGGER.info("Starting monitor_status loop") while not self.closed: _LOGGER.debug("Iteration... ") while not self.connected: _LOGGER.info("Not connected, re-connecting... ") await self.connect() if not self.connected: _LOGGER.warning("Not connected, sleeping for 10s... ") await asyncio.sleep(self._reconnection_timeout) continue await self.start_monitoring() if not self.connected: _LOGGER.warning("Start monitoring failed, sleeping for 10s...") await asyncio.sleep(self._reconnection_timeout) continue while True: await self._update_status() _LOGGER.debug("Got status!") if not self.connected: _LOGGER.info("Got connection broken, reconnecting!") break _LOGGER.info("Closed, quit monitoring.")
Stop monitoring and close connection.
def close(self): """Stop monitoring and close connection.""" _LOGGER.debug("Closing...") self.closed = True if self.connected: self._writer.close()
Clear all matching our user_id.
def purge_db(self): """ Clear all matching our user_id. """ with self.engine.begin() as db: purge_user(db, self.user_id)
Guess the type of a file.
def guess_type(self, path, allow_directory=True): """ Guess the type of a file. If allow_directory is False, don't consider the possibility that the file is a directory. """ if path.endswith('.ipynb'): return 'notebook' elif allow_directory and self.dir_exists(path): return 'directory' else: return 'file'
Get the id of a file in the database. This function is specific to this implementation of ContentsManager and is not in the base class.
def get_file_id(self, path): """ Get the id of a file in the database. This function is specific to this implementation of ContentsManager and is not in the base class. """ with self.engine.begin() as db: try: file_id = get_file_id(db, self.user_id, path) except NoSuchFile: self.no_such_entity(path) return file_id
Get a notebook from the database.
def _get_notebook(self, path, content, format): """ Get a notebook from the database. """ with self.engine.begin() as db: try: record = get_file( db, self.user_id, path, content, self.crypto.decrypt, ) except NoSuchFile: self.no_such_entity(path) return self._notebook_model_from_db(record, content)
Build a notebook model from database record.
def _notebook_model_from_db(self, record, content): """ Build a notebook model from database record. """ path = to_api_path(record['parent_name'] + record['name']) model = base_model(path) model['type'] = 'notebook' model['last_modified'] = model['created'] = record['created_at'] if content: content = reads_base64(record['content']) self.mark_trusted_cells(content, path) model['content'] = content model['format'] = 'json' self.validate_notebook_model(model) return model
Get a directory from the database.
def _get_directory(self, path, content, format): """ Get a directory from the database. """ with self.engine.begin() as db: try: record = get_directory( db, self.user_id, path, content ) except NoSuchDirectory: if self.file_exists(path): # TODO: It's awkward/expensive to have to check this to # return a 400 instead of 404. Consider just 404ing. self.do_400("Wrong type: %s" % path) else: self.no_such_entity(path) return self._directory_model_from_db(record, content)
Apply _notebook_model_from_db or _file_model_from_db to each entry in file_records depending on the result of guess_type.
def _convert_file_records(self, file_records): """ Apply _notebook_model_from_db or _file_model_from_db to each entry in file_records, depending on the result of `guess_type`. """ for record in file_records: type_ = self.guess_type(record['name'], allow_directory=False) if type_ == 'notebook': yield self._notebook_model_from_db(record, False) elif type_ == 'file': yield self._file_model_from_db(record, False, None) else: self.do_500("Unknown file type %s" % type_)
Build a directory model from database directory record.
def _directory_model_from_db(self, record, content): """ Build a directory model from database directory record. """ model = base_directory_model(to_api_path(record['name'])) if content: model['format'] = 'json' model['content'] = list( chain( self._convert_file_records(record['files']), ( self._directory_model_from_db(subdir, False) for subdir in record['subdirs'] ), ) ) return model
Build a file model from database record.
def _file_model_from_db(self, record, content, format): """ Build a file model from database record. """ # TODO: Most of this is shared with _notebook_model_from_db. path = to_api_path(record['parent_name'] + record['name']) model = base_model(path) model['type'] = 'file' model['last_modified'] = model['created'] = record['created_at'] if content: bcontent = record['content'] model['content'], model['format'], model['mimetype'] = from_b64( path, bcontent, format, ) return model
Save a notebook.
def _save_notebook(self, db, model, path): """ Save a notebook. Returns a validation message. """ nb_contents = from_dict(model['content']) self.check_and_sign(nb_contents, path) save_file( db, self.user_id, path, writes_base64(nb_contents), self.crypto.encrypt, self.max_file_size_bytes, ) # It's awkward that this writes to the model instead of returning. self.validate_notebook_model(model) return model.get('message')
Save a non - notebook file.
def _save_file(self, db, model, path): """ Save a non-notebook file. """ save_file( db, self.user_id, path, to_b64(model['content'], model.get('format', None)), self.crypto.encrypt, self.max_file_size_bytes, ) return None
Rename object from old_path to path.
def rename_file(self, old_path, path): """ Rename object from old_path to path. NOTE: This method is unfortunately named on the base class. It actually moves a file or a directory. """ with self.engine.begin() as db: try: if self.file_exists(old_path): rename_file(db, self.user_id, old_path, path) elif self.dir_exists(old_path): rename_directory(db, self.user_id, old_path, path) else: self.no_such_entity(path) except (FileExists, DirectoryExists): self.already_exists(path) except RenameRoot as e: self.do_409(str(e))
Delete object corresponding to path.
def delete_file(self, path): """ Delete object corresponding to path. """ if self.file_exists(path): self._delete_non_directory(path) elif self.dir_exists(path): self._delete_directory(path) else: self.no_such_entity(path)
Apply preprocessing steps to file/ notebook content that we re going to write to the database.
def preprocess_incoming_content(content, encrypt_func, max_size_bytes): """ Apply preprocessing steps to file/notebook content that we're going to write to the database. Applies ``encrypt_func`` to ``content`` and checks that the result is smaller than ``max_size_bytes``. """ encrypted = encrypt_func(content) if max_size_bytes != UNLIMITED and len(encrypted) > max_size_bytes: raise FileTooLarge() return encrypted
Add a new user if they don t already exist.
def ensure_db_user(db, user_id): """ Add a new user if they don't already exist. """ with ignore_unique_violation(): db.execute( users.insert().values(id=user_id), )
Delete a user and all of their resources.
def purge_user(db, user_id): """ Delete a user and all of their resources. """ db.execute(files.delete().where( files.c.user_id == user_id )) db.execute(directories.delete().where( directories.c.user_id == user_id )) db.execute(users.delete().where( users.c.id == user_id ))
Create a directory.
def create_directory(db, user_id, api_path): """ Create a directory. """ name = from_api_dirname(api_path) if name == '/': parent_name = null() parent_user_id = null() else: # Convert '/foo/bar/buzz/' -> '/foo/bar/' parent_name = name[:name.rindex('/', 0, -1) + 1] parent_user_id = user_id db.execute( directories.insert().values( name=name, user_id=user_id, parent_name=parent_name, parent_user_id=parent_user_id, ) )
Return a WHERE clause that matches entries in a directory.
def _is_in_directory(table, user_id, db_dirname): """ Return a WHERE clause that matches entries in a directory. Parameterized on table because this clause is re-used between files and directories. """ return and_( table.c.parent_name == db_dirname, table.c.user_id == user_id, )
Delete a directory.
def delete_directory(db, user_id, api_path): """ Delete a directory. """ db_dirname = from_api_dirname(api_path) try: result = db.execute( directories.delete().where( and_( directories.c.user_id == user_id, directories.c.name == db_dirname, ) ) ) except IntegrityError as error: if is_foreign_key_violation(error): raise DirectoryNotEmpty(api_path) else: raise rowcount = result.rowcount if not rowcount: raise NoSuchDirectory(api_path) return rowcount
Internal implementation of dir_exists.
def _dir_exists(db, user_id, db_dirname): """ Internal implementation of dir_exists. Expects a db-style path name. """ return db.execute( select( [func.count(directories.c.name)], ).where( and_( directories.c.user_id == user_id, directories.c.name == db_dirname, ), ) ).scalar() != 0
Return files in a directory.
def files_in_directory(db, user_id, db_dirname): """ Return files in a directory. """ fields = _file_default_fields() rows = db.execute( select( fields, ).where( _is_in_directory(files, user_id, db_dirname), ).order_by( files.c.user_id, files.c.parent_name, files.c.name, files.c.created_at, ).distinct( files.c.user_id, files.c.parent_name, files.c.name, ) ) return [to_dict_no_content(fields, row) for row in rows]
Return subdirectories of a directory.
def directories_in_directory(db, user_id, db_dirname): """ Return subdirectories of a directory. """ fields = _directory_default_fields() rows = db.execute( select( fields, ).where( _is_in_directory(directories, user_id, db_dirname), ) ) return [to_dict_no_content(fields, row) for row in rows]
Return the names of all files/ directories that are direct children of api_dirname.
def get_directory(db, user_id, api_dirname, content): """ Return the names of all files/directories that are direct children of api_dirname. If content is False, return a bare model containing just a database-style name. """ db_dirname = from_api_dirname(api_dirname) if not _dir_exists(db, user_id, db_dirname): raise NoSuchDirectory(api_dirname) if content: files = files_in_directory( db, user_id, db_dirname, ) subdirectories = directories_in_directory( db, user_id, db_dirname, ) else: files, subdirectories = None, None # TODO: Consider using namedtuples for these return values. return { 'name': db_dirname, 'files': files, 'subdirs': subdirectories, }
Return a WHERE clause matching the given API path and user_id.
def _file_where(user_id, api_path): """ Return a WHERE clause matching the given API path and user_id. """ directory, name = split_api_filepath(api_path) return and_( files.c.name == name, files.c.user_id == user_id, files.c.parent_name == directory, )
Return a SELECT statement that returns the latest N versions of a file.
def _select_file(user_id, api_path, fields, limit): """ Return a SELECT statement that returns the latest N versions of a file. """ query = select(fields).where( _file_where(user_id, api_path), ).order_by( _file_creation_order(), ) if limit is not None: query = query.limit(limit) return query
Default fields returned by a file query.
def _file_default_fields(): """ Default fields returned by a file query. """ return [ files.c.name, files.c.created_at, files.c.parent_name, ]
Get file data for the given user_id path and query_fields. The query_fields parameter specifies which database fields should be included in the returned file data.
def _get_file(db, user_id, api_path, query_fields, decrypt_func): """ Get file data for the given user_id, path, and query_fields. The query_fields parameter specifies which database fields should be included in the returned file data. """ result = db.execute( _select_file(user_id, api_path, query_fields, limit=1), ).first() if result is None: raise NoSuchFile(api_path) if files.c.content in query_fields: return to_dict_with_content(query_fields, result, decrypt_func) else: return to_dict_no_content(query_fields, result)
Get file data for the given user_id and path.
def get_file(db, user_id, api_path, include_content, decrypt_func): """ Get file data for the given user_id and path. Include content only if include_content=True. """ query_fields = _file_default_fields() if include_content: query_fields.append(files.c.content) return _get_file(db, user_id, api_path, query_fields, decrypt_func)
Get the value in the id column for the file with the given user_id and path.
def get_file_id(db, user_id, api_path): """ Get the value in the 'id' column for the file with the given user_id and path. """ return _get_file( db, user_id, api_path, [files.c.id], unused_decrypt_func, )['id']
Delete a file.
def delete_file(db, user_id, api_path): """ Delete a file. TODO: Consider making this a soft delete. """ result = db.execute( files.delete().where( _file_where(user_id, api_path) ) ) rowcount = result.rowcount if not rowcount: raise NoSuchFile(api_path) return rowcount
Check if a file exists.
def file_exists(db, user_id, path): """ Check if a file exists. """ try: get_file( db, user_id, path, include_content=False, decrypt_func=unused_decrypt_func, ) return True except NoSuchFile: return False
Rename a file.
def rename_file(db, user_id, old_api_path, new_api_path): """ Rename a file. """ # Overwriting existing files is disallowed. if file_exists(db, user_id, new_api_path): raise FileExists(new_api_path) old_dir, old_name = split_api_filepath(old_api_path) new_dir, new_name = split_api_filepath(new_api_path) if old_dir != new_dir: raise ValueError( dedent( """ Can't rename object to new directory. Old Path: {old_api_path} New Path: {new_api_path} """.format( old_api_path=old_api_path, new_api_path=new_api_path ) ) ) db.execute( files.update().where( _file_where(user_id, old_api_path), ).values( name=new_name, created_at=func.now(), ) )
Rename a directory.
def rename_directory(db, user_id, old_api_path, new_api_path): """ Rename a directory. """ old_db_path = from_api_dirname(old_api_path) new_db_path = from_api_dirname(new_api_path) if old_db_path == '/': raise RenameRoot('Renaming the root directory is not permitted.') # Overwriting existing directories is disallowed. if _dir_exists(db, user_id, new_db_path): raise DirectoryExists(new_api_path) # Set this foreign key constraint to deferred so it's not violated # when we run the first statement to update the name of the directory. db.execute('SET CONSTRAINTS ' 'pgcontents.directories_parent_user_id_fkey DEFERRED') # Update name column for the directory that's being renamed db.execute( directories.update().where( and_( directories.c.user_id == user_id, directories.c.name == old_db_path, ) ).values( name=new_db_path, ) ) # Update the name and parent_name of any descendant directories. Do # this in a single statement so the non-deferrable check constraint # is satisfied. db.execute( directories.update().where( and_( directories.c.user_id == user_id, directories.c.name.startswith(old_db_path), directories.c.parent_name.startswith(old_db_path), ) ).values( name=func.concat( new_db_path, func.right(directories.c.name, -func.length(old_db_path)) ), parent_name=func.concat( new_db_path, func.right( directories.c.parent_name, -func.length(old_db_path) ) ), ) )
Save a file.
def save_file(db, user_id, path, content, encrypt_func, max_size_bytes): """ Save a file. TODO: Update-then-insert is probably cheaper than insert-then-update. """ content = preprocess_incoming_content( content, encrypt_func, max_size_bytes, ) directory, name = split_api_filepath(path) with db.begin_nested() as savepoint: try: res = db.execute( files.insert().values( name=name, user_id=user_id, parent_name=directory, content=content, ) ) except IntegrityError as error: # The file already exists, so overwrite its content with the newer # version. if is_unique_violation(error): savepoint.rollback() res = db.execute( files.update().where( _file_where(user_id, path), ).values( content=content, created_at=func.now(), ) ) else: # Unknown error. Reraise raise return res
Create a generator of decrypted files.
def generate_files(engine, crypto_factory, min_dt=None, max_dt=None, logger=None): """ Create a generator of decrypted files. Files are yielded in ascending order of their timestamp. This function selects all current notebooks (optionally, falling within a datetime range), decrypts them, and returns a generator yielding dicts, each containing a decoded notebook and metadata including the user, filepath, and timestamp. Parameters ---------- engine : SQLAlchemy.engine Engine encapsulating database connections. crypto_factory : function[str -> Any] A function from user_id to an object providing the interface required by PostgresContentsManager.crypto. Results of this will be used for decryption of the selected notebooks. min_dt : datetime.datetime, optional Minimum last modified datetime at which a file will be included. max_dt : datetime.datetime, optional Last modified datetime at and after which a file will be excluded. logger : Logger, optional """ return _generate_notebooks(files, files.c.created_at, engine, crypto_factory, min_dt, max_dt, logger)
Delete all database records for the given user_id.
def purge_remote_checkpoints(db, user_id): """ Delete all database records for the given user_id. """ db.execute( remote_checkpoints.delete().where( remote_checkpoints.c.user_id == user_id, ) )
Create a generator of decrypted remote checkpoints.
def generate_checkpoints(engine, crypto_factory, min_dt=None, max_dt=None, logger=None): """ Create a generator of decrypted remote checkpoints. Checkpoints are yielded in ascending order of their timestamp. This function selects all notebook checkpoints (optionally, falling within a datetime range), decrypts them, and returns a generator yielding dicts, each containing a decoded notebook and metadata including the user, filepath, and timestamp. Parameters ---------- engine : SQLAlchemy.engine Engine encapsulating database connections. crypto_factory : function[str -> Any] A function from user_id to an object providing the interface required by PostgresContentsManager.crypto. Results of this will be used for decryption of the selected notebooks. min_dt : datetime.datetime, optional Minimum last modified datetime at which a file will be included. max_dt : datetime.datetime, optional Last modified datetime at and after which a file will be excluded. logger : Logger, optional """ return _generate_notebooks(remote_checkpoints, remote_checkpoints.c.last_modified, engine, crypto_factory, min_dt, max_dt, logger)
See docstrings for generate_files and generate_checkpoints.
def _generate_notebooks(table, timestamp_column, engine, crypto_factory, min_dt, max_dt, logger): """ See docstrings for `generate_files` and `generate_checkpoints`. Parameters ---------- table : SQLAlchemy.Table Table to fetch notebooks from, `files` or `remote_checkpoints. timestamp_column : SQLAlchemy.Column `table`'s column storing timestamps, `created_at` or `last_modified`. engine : SQLAlchemy.engine Engine encapsulating database connections. crypto_factory : function[str -> Any] A function from user_id to an object providing the interface required by PostgresContentsManager.crypto. Results of this will be used for decryption of the selected notebooks. min_dt : datetime.datetime Minimum last modified datetime at which a file will be included. max_dt : datetime.datetime Last modified datetime at and after which a file will be excluded. logger : Logger """ where_conds = [] if min_dt is not None: where_conds.append(timestamp_column >= min_dt) if max_dt is not None: where_conds.append(timestamp_column < max_dt) if table is files: # Only select files that are notebooks where_conds.append(files.c.name.like(u'%.ipynb')) # Query for notebooks satisfying the conditions. query = select([table]).order_by(timestamp_column) for cond in where_conds: query = query.where(cond) result = engine.execute(query) # Decrypt each notebook and yield the result. for nb_row in result: try: # The decrypt function depends on the user user_id = nb_row['user_id'] decrypt_func = crypto_factory(user_id).decrypt nb_dict = to_dict_with_content(table.c, nb_row, decrypt_func) if table is files: # Correct for files schema differing somewhat from checkpoints. nb_dict['path'] = nb_dict['parent_name'] + nb_dict['name'] nb_dict['last_modified'] = nb_dict['created_at'] # For 'content', we use `reads_base64` directly. If the db content # format is changed from base64, the decoding should be changed # here as well. yield { 'id': nb_dict['id'], 'user_id': user_id, 'path': to_api_path(nb_dict['path']), 'last_modified': nb_dict['last_modified'], 'content': reads_base64(nb_dict['content']), } except CorruptedFile: if logger is not None: logger.warning( 'Corrupted file with id %d in table %s.' % (nb_row['id'], table.name) )
Re - encrypt a row from table with id of row_id.
def reencrypt_row_content(db, table, row_id, decrypt_func, encrypt_func, logger): """ Re-encrypt a row from ``table`` with ``id`` of ``row_id``. """ q = (select([table.c.content]) .with_for_update() .where(table.c.id == row_id)) [(content,)] = db.execute(q) logger.info("Begin encrypting %s row %s.", table.name, row_id) db.execute( table .update() .where(table.c.id == row_id) .values(content=encrypt_func(decrypt_func(content))) ) logger.info("Done encrypting %s row %s.", table.name, row_id)
Get all file ids for a user.
def select_file_ids(db, user_id): """ Get all file ids for a user. """ return list( db.execute( select([files.c.id]) .where(files.c.user_id == user_id) ) )
Get all file ids for a user.
def select_remote_checkpoint_ids(db, user_id): """ Get all file ids for a user. """ return list( db.execute( select([remote_checkpoints.c.id]) .where(remote_checkpoints.c.user_id == user_id) ) )
Re - encrypt all of the files and checkpoints for a single user.
def reencrypt_user_content(engine, user_id, old_decrypt_func, new_encrypt_func, logger): """ Re-encrypt all of the files and checkpoints for a single user. """ logger.info("Begin re-encryption for user %s", user_id) with engine.begin() as db: # NOTE: Doing both of these operations in one transaction depends for # correctness on the fact that the creation of new checkpoints always # involves writing new data into the database from Python, rather than # simply copying data inside the DB. # If we change checkpoint creation so that it does an in-database copy, # then we need to split this transaction to ensure that # file-reencryption is complete before checkpoint-reencryption starts. # If that doesn't happen, it will be possible for a user to create a # new checkpoint in a transaction that hasn't seen the completed # file-reencryption process, but we might not see that checkpoint here, # which means that we would never update the content of that checkpoint # to the new encryption key. logger.info("Re-encrypting files for %s", user_id) for (file_id,) in select_file_ids(db, user_id): reencrypt_row_content( db, files, file_id, old_decrypt_func, new_encrypt_func, logger, ) logger.info("Re-encrypting checkpoints for %s", user_id) for (cp_id,) in select_remote_checkpoint_ids(db, user_id): reencrypt_row_content( db, remote_checkpoints, cp_id, old_decrypt_func, new_encrypt_func, logger, ) logger.info("Finished re-encryption for user %s", user_id)
Convert a secret key and a user ID into an encryption key to use with a cryptography. fernet. Fernet.
def derive_single_fernet_key(password, user_id): """ Convert a secret key and a user ID into an encryption key to use with a ``cryptography.fernet.Fernet``. Taken from https://cryptography.io/en/latest/fernet/#using-passwords-with-fernet Parameters ---------- password : unicode ascii-encodable key to derive user_id : unicode ascii-encodable user_id to use as salt """ password = ascii_unicode_to_bytes(password) user_id = ascii_unicode_to_bytes(user_id) kdf = PBKDF2HMAC( algorithm=hashes.SHA256(), length=32, salt=user_id, iterations=100000, backend=default_backend(), ) return base64.urlsafe_b64encode(kdf.derive(password))
Derive a list of per - user Fernet keys from a list of master keys and a username.
def derive_fallback_fernet_keys(passwords, user_id): """ Derive a list of per-user Fernet keys from a list of master keys and a username. If a None is encountered in ``passwords``, it is forwarded. Parameters ---------- passwords : list[unicode] List of ascii-encodable keys to derive. user_id : unicode or None ascii-encodable user_id to use as salt """ # Normally I wouldn't advocate for these kinds of assertions, but we really # really really don't want to mess up deriving encryption keys. assert isinstance(passwords, (list, tuple)), \ "Expected list or tuple of keys, got %s." % type(passwords) def derive_single_allow_none(k): if k is None: return None return derive_single_fernet_key(k, user_id).decode('ascii') return list(map(derive_single_allow_none, passwords))
Create and return a function suitable for passing as a crypto_factory to pgcontents. utils. sync. reencrypt_all_users
def single_password_crypto_factory(password): """ Create and return a function suitable for passing as a crypto_factory to ``pgcontents.utils.sync.reencrypt_all_users`` The factory here returns a ``FernetEncryption`` that uses a key derived from ``password`` and salted with the supplied user_id. """ @memoize_single_arg def factory(user_id): return FernetEncryption( Fernet(derive_single_fernet_key(password, user_id)) ) return factory
Decorator memoizing a single - argument function
def memoize_single_arg(f): """ Decorator memoizing a single-argument function """ memo = {} @wraps(f) def memoized_f(arg): try: return memo[arg] except KeyError: result = memo[arg] = f(arg) return result return memoized_f
Get the name from a column - like SQLAlchemy expression.
def _get_name(column_like): """ Get the name from a column-like SQLAlchemy expression. Works for Columns and Cast expressions. """ if isinstance(column_like, Column): return column_like.name elif isinstance(column_like, Cast): return column_like.clause.name
Convert a SQLAlchemy row that does not contain a content field to a dict.
def to_dict_no_content(fields, row): """ Convert a SQLAlchemy row that does not contain a 'content' field to a dict. If row is None, return None. Raises AssertionError if there is a field named 'content' in ``fields``. """ assert(len(fields) == len(row)) field_names = list(map(_get_name, fields)) assert 'content' not in field_names, "Unexpected content field." return dict(zip(field_names, row))
Convert a SQLAlchemy row that contains a content field to a dict.
def to_dict_with_content(fields, row, decrypt_func): """ Convert a SQLAlchemy row that contains a 'content' field to a dict. ``decrypt_func`` will be applied to the ``content`` field of the row. If row is None, return None. Raises AssertionError if there is no field named 'content' in ``fields``. """ assert(len(fields) == len(row)) field_names = list(map(_get_name, fields)) assert 'content' in field_names, "Missing content field." result = dict(zip(field_names, row)) result['content'] = decrypt_func(result['content']) return result
Create a checkpoint of the current state of a notebook
def create_notebook_checkpoint(self, nb, path): """Create a checkpoint of the current state of a notebook Returns a checkpoint_id for the new checkpoint. """ b64_content = writes_base64(nb) with self.engine.begin() as db: return save_remote_checkpoint( db, self.user_id, path, b64_content, self.crypto.encrypt, self.max_file_size_bytes, )
Create a checkpoint of the current state of a file
def create_file_checkpoint(self, content, format, path): """Create a checkpoint of the current state of a file Returns a checkpoint_id for the new checkpoint. """ try: b64_content = to_b64(content, format) except ValueError as e: self.do_400(str(e)) with self.engine.begin() as db: return save_remote_checkpoint( db, self.user_id, path, b64_content, self.crypto.encrypt, self.max_file_size_bytes, )
delete a checkpoint for a file
def delete_checkpoint(self, checkpoint_id, path): """delete a checkpoint for a file""" with self.engine.begin() as db: return delete_single_remote_checkpoint( db, self.user_id, path, checkpoint_id, )
Get the content of a checkpoint.
def get_checkpoint_content(self, checkpoint_id, path): """Get the content of a checkpoint.""" with self.engine.begin() as db: return get_remote_checkpoint( db, self.user_id, path, checkpoint_id, self.crypto.decrypt, )['content']
Return a list of checkpoints for a given file
def list_checkpoints(self, path): """Return a list of checkpoints for a given file""" with self.engine.begin() as db: return list_remote_checkpoints(db, self.user_id, path)
Rename all checkpoints for old_path to new_path.
def rename_all_checkpoints(self, old_path, new_path): """Rename all checkpoints for old_path to new_path.""" with self.engine.begin() as db: return move_remote_checkpoints( db, self.user_id, old_path, new_path, )
Delete all checkpoints for the given path.
def delete_all_checkpoints(self, path): """Delete all checkpoints for the given path.""" with self.engine.begin() as db: delete_remote_checkpoints(db, self.user_id, path)
Purge all database records for the current user.
def purge_db(self): """ Purge all database records for the current user. """ with self.engine.begin() as db: purge_remote_checkpoints(db, self.user_id)
Resolve a path based on a dictionary of manager prefixes.
def _resolve_path(path, manager_dict): """ Resolve a path based on a dictionary of manager prefixes. Returns a triple of (prefix, manager, manager_relative_path). """ path = normalize_api_path(path) parts = path.split('/') # Try to find a sub-manager for the first subdirectory. mgr = manager_dict.get(parts[0]) if mgr is not None: return parts[0], mgr, '/'.join(parts[1:]) # Try to find use the root manager, if one was supplied. mgr = manager_dict.get('') if mgr is not None: return '', mgr, path raise HTTPError( 404, "Couldn't resolve path [{path}] and " "no root manager supplied!".format(path=path) )
Get an argument either from kwargs or from the first entry in args. Raises a TypeError if argname not in kwargs and len ( args ) == 0.
def _get_arg(argname, args, kwargs): """ Get an argument, either from kwargs or from the first entry in args. Raises a TypeError if argname not in kwargs and len(args) == 0. Mutates kwargs in place if the value is found in kwargs. """ try: return kwargs.pop(argname), args except KeyError: pass try: return args[0], args[1:] except IndexError: raise TypeError("No value passed for %s" % argname)
Prefix all path entries in model with the given prefix.
def _apply_prefix(prefix, model): """ Prefix all path entries in model with the given prefix. """ if not isinstance(model, dict): raise TypeError("Expected dict for model, got %s" % type(model)) # We get unwanted leading/trailing slashes if prefix or model['path'] are # '', both of which are legal values. model['path'] = '/'.join((prefix, model['path'])).strip('/') if model['type'] in ('notebook', 'file'): return model if model['type'] != 'directory': raise ValueError("Unknown model type %s." % type(model)) content = model.get('content', None) if content is not None: for sub_model in content: _apply_prefix(prefix, sub_model) return model
Decorator for methods that accept path as a first argument.
def path_dispatch1(mname, returns_model): """ Decorator for methods that accept path as a first argument. """ def _wrapper(self, *args, **kwargs): path, args = _get_arg('path', args, kwargs) prefix, mgr, mgr_path = _resolve_path(path, self.managers) result = getattr(mgr, mname)(mgr_path, *args, **kwargs) if returns_model and prefix: return _apply_prefix(prefix, result) else: return result return _wrapper
Parameterized decorator for methods that accept path as a second argument.
def path_dispatch_kwarg(mname, path_default, returns_model): """ Parameterized decorator for methods that accept path as a second argument. """ def _wrapper(self, path=path_default, **kwargs): prefix, mgr, mgr_path = _resolve_path(path, self.managers) result = getattr(mgr, mname)(path=mgr_path, **kwargs) if returns_model and prefix: return _apply_prefix(prefix, result) else: return result return _wrapper
Decorator for methods accepting old_path and new_path.
def path_dispatch_old_new(mname, returns_model): """ Decorator for methods accepting old_path and new_path. """ def _wrapper(self, old_path, new_path, *args, **kwargs): old_prefix, old_mgr, old_mgr_path = _resolve_path( old_path, self.managers ) new_prefix, new_mgr, new_mgr_path = _resolve_path( new_path, self.managers, ) if old_mgr is not new_mgr: # TODO: Consider supporting this via get+delete+save. raise HTTPError( 400, "Can't move files between backends ({old} -> {new})".format( old=old_path, new=new_path, ) ) assert new_prefix == old_prefix result = getattr(new_mgr, mname)( old_mgr_path, new_mgr_path, *args, **kwargs ) if returns_model and new_prefix: return _apply_prefix(new_prefix, result) else: return result return _wrapper
Strip slashes from directories before updating.
def _managers_changed(self, name, old, new): """ Strip slashes from directories before updating. """ for key in new: if '/' in key: raise ValueError( "Expected directory names w/o slashes. Got [%s]" % key ) self.managers = {k.strip('/'): v for k, v in new.items()}
Special case handling for listing root dir.
def get(self, path, content=True, type=None, format=None): """ Special case handling for listing root dir. """ path = normalize_api_path(path) if path: return self.__get(path, content=content, type=type, format=format) if not content: return base_directory_model('') extra_content = self._extra_root_dirs() rm = self.root_manager if rm is None: root_model = base_directory_model('') root_model.update( format='json', content=extra_content, ) else: root_model = rm.get( path, content=content, type=type, format=format, ) # Append the extra directories. root_model['content'].extend(extra_content) return root_model
Ensure that roots of our managers can t be deleted. This should be enforced by https:// github. com/ ipython/ ipython/ pull/ 8168 but rogue implementations might override this behavior.
def delete(self, path): """ Ensure that roots of our managers can't be deleted. This should be enforced by https://github.com/ipython/ipython/pull/8168, but rogue implementations might override this behavior. """ path = normalize_api_path(path) if path in self.managers: raise HTTPError( 400, "Can't delete root of %s" % self.managers[path] ) return self.__delete(path)
Resolve paths with.. to normalized paths raising an error if the final result is outside root.
def normalize_api_path(api_path): """ Resolve paths with '..' to normalized paths, raising an error if the final result is outside root. """ normalized = posixpath.normpath(api_path.strip('/')) if normalized == '.': normalized = '' elif normalized.startswith('..'): raise PathOutsideRoot(normalized) return normalized
Split an API file path into directory and name.
def split_api_filepath(path): """ Split an API file path into directory and name. """ parts = path.rsplit('/', 1) if len(parts) == 1: name = parts[0] dirname = '/' else: name = parts[1] dirname = parts[0] + '/' return from_api_dirname(dirname), name
Write a notebook as base64.
def writes_base64(nb, version=NBFORMAT_VERSION): """ Write a notebook as base64. """ return b64encode(writes(nb, version=version).encode('utf-8'))
Read a notebook from base64.
def reads_base64(nb, as_version=NBFORMAT_VERSION): """ Read a notebook from base64. """ try: return reads(b64decode(nb).decode('utf-8'), as_version=as_version) except Exception as e: raise CorruptedFile(e)
Decode base64 data of unknown format.
def _decode_unknown_from_base64(path, bcontent): """ Decode base64 data of unknown format. Attempts to interpret data as utf-8, falling back to ascii on failure. """ content = b64decode(bcontent) try: return (content.decode('utf-8'), 'text') except UnicodeError: pass return bcontent.decode('ascii'), 'base64'
Decode base64 content for a file.
def from_b64(path, bcontent, format): """ Decode base64 content for a file. format: If 'text', the contents will be decoded as UTF-8. If 'base64', do nothing. If not specified, try to decode as UTF-8, and fall back to base64 Returns a triple of decoded_content, format, and mimetype. """ decoders = { 'base64': lambda path, bcontent: (bcontent.decode('ascii'), 'base64'), 'text': _decode_text_from_base64, None: _decode_unknown_from_base64, } try: content, real_format = decoders[format](path, bcontent) except HTTPError: # Pass through HTTPErrors, since we intend for them to bubble all the # way back to the API layer. raise except Exception as e: # Anything else should be wrapped in a CorruptedFile, since it likely # indicates misconfiguration of encryption. raise CorruptedFile(e) default_mimes = { 'text': 'text/plain', 'base64': 'application/octet-stream', } mimetype = mimetypes.guess_type(path)[0] or default_mimes[real_format] return content, real_format, mimetype
Return an iterable of all prefix directories of path descending from root.
def prefix_dirs(path): """ Return an iterable of all prefix directories of path, descending from root. """ _dirname = posixpath.dirname path = path.strip('/') out = [] while path != '': path = _dirname(path) out.append(path) return reversed(out)
Decorator for converting PathOutsideRoot errors to 404s.
def outside_root_to_404(fn): """ Decorator for converting PathOutsideRoot errors to 404s. """ @wraps(fn) def wrapped(*args, **kwargs): try: return fn(*args, **kwargs) except PathOutsideRoot as e: raise HTTPError(404, "Path outside root: [%s]" % e.args[0]) return wrapped
Create a user.
def create_user(db_url, user): """ Create a user. """ PostgresCheckpoints( db_url=db_url, user_id=user, create_user_on_startup=True, )
Split an iterable of models into a list of file paths and a list of directory paths.
def _separate_dirs_files(models): """ Split an iterable of models into a list of file paths and a list of directory paths. """ dirs = [] files = [] for model in models: if model['type'] == 'directory': dirs.append(model['path']) else: files.append(model['path']) return dirs, files