def get_variables(self, data_source):
'''Returns a list of all stored variables corresponding to the input data source
Keyword arguments:
@param data_source -- a string denoting the name of a data source; collection names
corresponding to data from this data source are expected to
start with the data source name
'''
(host, port) = DBUtils.get_db_host_and_port()
if port != self.db_port:
port = self.db_port
client = pm.MongoClient(host=host, port=port)
database = client[self.db_name]
collection_names = database.list_collection_names()
variable_list = []
for collection_name in collection_names:
if collection_name == 'system.indexes' or \
not collection_name.startswith(data_source):
continue
collection = database[collection_name]
variable_names = DataUtils.get_variable_list(
collection_name, collection)
variable_list.extend(variable_names)
return variable_list
def write_metadata(self, config_params):
'''If a "black_box_metadata" collection doesn't exist in the black box database,
creates the collection and stores the metadata for all logged variables there.
@param config_params -- a black_box.config.config_params.ConfigParams instance
'''
if config_params:
(host, port) = DBUtils.get_db_host_and_port()
if port != self.db_port:
port = self.db_port
client = pm.MongoClient(host=host, port=port)
db = client[self.db_name]
collection_names = db.list_collection_names()
if 'black_box_metadata' in collection_names:
print('[write_metadata] {0} already has a "black_box_metadata" collection'.format(self.db_name))
else:
print('[write_metadata] Saving metadata')
collection = db['black_box_metadata']
if config_params.ros:
for topic_params in config_params.ros.topic:
collection_name = ConfigUtils.get_full_variable_name('ros', topic_params.name)
if topic_params.metadata:
metadata = {}
metadata['collection_name'] = collection_name
metadata['ros'] = {}
metadata['ros']['topic_name'] = topic_params.metadata.topic_name
metadata['ros']['msg_type'] = topic_params.metadata.msg_type
metadata['ros']['direct_msg_mapping'] = topic_params.metadata.direct_msg_mapping
collection.insert_one(metadata)
if config_params.zmq:
for topic_params in config_params.zmq.topics:
collection_name = ConfigUtils.get_full_variable_name('zmq', topic_params.name)
if topic_params.metadata:
metadata = {}
metadata['collection_name'] = collection_name
metadata['ros'] = {}
metadata['ros']['topic_name'] = topic_params.metadata.topic_name
metadata['ros']['msg_type'] = topic_params.metadata.msg_type
metadata['ros']['direct_msg_mapping'] = topic_params.metadata.direct_msg_mapping
collection.insert_one(metadata)
else:
raise AssertionError('[write_metadata] config_params needs to be of type ' + \
'black_box.config.config_params.ConfigParams')
def log_data(self, variable, timestamp, data):
'''Logs the data dictionary for the given variable;
adds the timestamp to the data dictionary before logging.
@param variable -- name of a variable to be logged
@param timestamp -- a timestamp (epoch in seconds)
@param data -- a dictionary to be logged
'''
(host, port) = DBUtils.get_db_host_and_port()
if port != self.db_port:
port = self.db_port
client = pm.MongoClient(host=host, port=port)
db = client[self.db_name]
collection = db[variable]
data['timestamp'] = timestamp
collection.insert_one(data)
def get_latest_data(self, collection_name, variable_names):
'''Returns a dictionary in which each key is a full variable name
(namely a variable name of the format "collection_name/variable_name",
where "variable_name" is a flattened version of a variable stored in the collection)
and the value is a list string "[timestamp, value]", namely the latest value
of the variable together with its timestamp (the list is a string to allow "value"
to be of different types). If the given collection does not exist or
there are no documents in it, returns an empty dictionary.
Keyword arguments:
@param collection_name -- name corresponding to a collection from the log database
@param variable_names -- list of variable names that should be retrieved from the collection
'''
(host, port) = DBUtils.get_db_host_and_port()
if port != self.db_port:
port = self.db_port
client = pm.MongoClient(host=host, port=port)
database = client[self.db_name]
collection = database[collection_name]
doc = collection.find_one(sort=[('timestamp', pm.DESCENDING)])
var_data = {}
var_full_names = {}
for var_name in variable_names:
full_var_name = '{0}/{1}'.format(collection_name, var_name)
var_data[full_var_name] = None
var_full_names[var_name] = full_var_name
if doc:
for var_name in variable_names:
var_value = DataUtils.get_var_value(doc, var_name)
var_data[var_full_names[var_name]] = '[{0}, {1}]'.format(
doc['timestamp'], var_value)
return var_data
