Add a method for getting the light sensor data.

features/light.py

@@ -0,0 +1,30 @@
+from collections.abc import Collection
+
+import pandas as pd
+
+from config.models import Participant, LightSensor
+from setup import db_engine, session
+
+
+def get_light_data(usernames: Collection) -> pd.DataFrame:
+    """
+    Read the data from the light sensor table and return it in a dataframe.
+
+    Parameters
+    ----------
+    usernames: Collection
+        A list of usernames to put into the WHERE condition.
+
+    Returns
+    -------
+    df_light: pd.DataFrame
+        A dataframe of light data.
+    """
+    query_light = (
+        session.query(LightSensor, Participant.username)
+        .filter(Participant.id == LightSensor.participant_id)
+        .filter(Participant.username.in_(usernames))
+    )
+    with db_engine.connect() as connection:
+        df_light = pd.read_sql(query_light.statement, connection)
+    return df_light