stream_sim module

class stream_sim.DataLoader(*args, **kwargs)[source]

Bases: object

Singleton DataLoader class for loading and retrieving data in batches.

This class provides functionality to load data and retrieve it in batches, maintaining a singleton instance throughout the application.

df

The underlying data in a pandas DataFrame.

Type:: pandas.DataFrame

batch_size

The size of each data batch.

Type:: int

row_ind

The current row index.

Type:: int

get_next()[source]

Get the next batch of data.

This method retrieves the next batch of data from the underlying DataFrame based on the current row index and batch size. It also updates the row index for the next batch.

Returns:: The next batch of data.
Return type:: pandas.DataFrame

stream_sim.fetch_sensor_data()[source]

Fetches sensor data from the data loader and returns it as a JSON response.

Returns:: A JSON response containing the fetched sensor data.
Return type:: Response

stream_sim.get_data(config)[source]

Retrieves the data from either a database table or a CSV file based on the configuration.

Parameters:: config (dict) – Configuration dictionary containing the ‘DATA_TYPE’, ‘DATASET’ path, ‘IDs’, and ‘START_TIME’, DB_TABLE, DATE_TIME_COL.
Returns:: Data retrieved from the database table or CSV file.
Return type:: result (pandas.DataFrame)

stream_sim.get_db_engine()[source]

Returns a SQLAlchemy engine for connecting to the database.

Returns:: SQLAlchemy engine object.
Return type:: engine (sqlalchemy.engine.base.Engine)

stream_sim.get_ids()[source]

Retrieves the target IDs.

Returns:: List of IDs or None if not specified in the config.
Return type:: list or None

stream_sim.get_query_result(query, db_conn, params=[])[source]

Executes a SQL query on the database connection and returns the result as a Pandas DataFrame.

Parameters:

query (str) – SQL query to be executed.
db_conn (sqlalchemy.engine.base.Connection) – Database connection object.
params (list, optional) – Parameters to be passed to the SQL query. Defaults to [].

Returns:

Result of the SQL query as a Pandas DataFrame.

Return type:

result (pandas.DataFrame)

stream_sim.get_series_from_db(db_conn, table_name, ids=None, id_column=None, start_time=None)[source]

Retrieves the series data for specific IDs from the database starting from the specified time.

Parameters:

db_conn (sqlalchemy.engine.base.Connection) – Database connection object.
table_name (str) – Name of the table to retrieve the series data from.
ids (list or None, optional) – IDs for which to retrieve the series data. Defaults to None.
id_column (str or None, optional) – Name of the ID column in the database table. Defaults to None.
start_time (str or None, optional) – Start time from which to retrieve the series data. Defaults to None.

Returns:

Result of the SQL query as a Pandas DataFrame.

Return type:

result (pandas.DataFrame)

stream_sim.init_dataloader()[source]

Initializes the DataLoader with the fetched data based on the configuration.

Returns:: Initialized DataLoader instance.
Return type:: DataLoader

stream_sim.root()[source]

Redirects the root URL to the ‘fetch_sensor_data’ endpoint.

Returns:: A redirection response to the ‘fetch_sensor_data’ endpoint.
Return type:: Response