sem8-iot-test/agent/src/file_datasource.py

151 lines
4.9 KiB
Python

import csv
import time
from datetime import datetime
from pathlib import Path
from typing import Optional, List
from domain.accelerometer import Accelerometer
from domain.gps import Gps
from domain.aggregated_data import AggregatedData
import config
class FileDatasource:
def __init__(self, accelerometer_filename: str, gps_filename: str) -> None:
self.accelerometer_filename = accelerometer_filename
self.gps_filename = gps_filename
self._acc_f = None
self._gps_f = None
self._acc_reader: Optional[csv.reader] = None
self._gps_reader: Optional[csv.reader] = None
self._started = False
def startReading(self, *args, **kwargs):
"""Must be called before read()"""
if self._started:
return
if not Path(self.accelerometer_filename).exists():
raise FileNotFoundError(f"Accelerometer file not found: {self.accelerometer_filename}")
if not Path(self.gps_filename).exists():
raise FileNotFoundError(f"GPS file not found: {self.gps_filename}")
self._open_files()
self._started = True
def stopReading(self, *args, **kwargs):
"""Must be called when finishing reading"""
self._close_files()
self._started = False
def read(self) -> AggregatedData:
"""Return one combined sample (acc + gps)."""
if not self._started:
raise RuntimeError("Datasource is not started. Call startReading() before read().")
acc_row = self._get_next_row(self._acc_reader, source="acc")
gps_row = self._get_next_row(self._gps_reader, source="gps")
acc = self._parse_acc(acc_row)
gps = self._parse_gps(gps_row)
# IMPORTANT: timing belongs to datasource (not MQTT / main.py)
if config.DELAY and config.DELAY > 0:
time.sleep(float(config.DELAY))
return AggregatedData(
accelerometer=acc,
gps=gps,
timestamp=datetime.utcnow(),
user_id=config.USER_ID,
)
# ---------------- internal ----------------
def _open_files(self) -> None:
self._close_files()
self._acc_f = open(self.accelerometer_filename, "r", newline="", encoding="utf-8")
self._gps_f = open(self.gps_filename, "r", newline="", encoding="utf-8")
self._acc_reader = csv.reader(self._acc_f, skipinitialspace=True)
self._gps_reader = csv.reader(self._gps_f, skipinitialspace=True)
# File pointer is already at 0 right after open(), so no need to rewind here.
# Skip header row once.
next(self._acc_reader, None)
next(self._gps_reader, None)
def _close_files(self) -> None:
for f in (self._acc_f, self._gps_f):
try:
if f is not None:
f.close()
except Exception:
pass
self._acc_f = None
self._gps_f = None
self._acc_reader = None
self._gps_reader = None
def _rewind_acc(self) -> None:
if self._acc_f is None:
raise RuntimeError("Accelerometer file is not open.")
self._acc_f.seek(0)
self._acc_reader = csv.reader(self._acc_f, skipinitialspace=True)
next(self._acc_reader, None) # skip header row
def _rewind_gps(self) -> None:
if self._gps_f is None:
raise RuntimeError("GPS file is not open.")
self._gps_f.seek(0)
self._gps_reader = csv.reader(self._gps_f, skipinitialspace=True)
next(self._gps_reader, None) # skip header row
def _get_next_row(self, reader, source: str) -> List[str]:
"""Get the next valid row from the reader."""
if reader is None:
raise RuntimeError("Reader is not initialized.")
while True:
row = next(reader, None)
if row is None:
# EOF -> rewind & continue
if source == "acc":
self._rewind_acc()
reader = self._acc_reader
else:
self._rewind_gps()
reader = self._gps_reader
continue
if not row or not any(cell.strip() for cell in row):
continue
return row
@staticmethod
def _parse_acc(row: List[str]) -> Accelerometer:
if len(row) < 3:
raise ValueError(f"Accelerometer row must have 3 values (x,y,z). Got: {row}")
try:
x = int(row[0])
y = int(row[1])
z = int(row[2])
except ValueError as e:
raise ValueError(f"Invalid accelerometer values (expected integers): {row}") from e
return Accelerometer(x=x, y=y, z=z)
@staticmethod
def _parse_gps(row: List[str]) -> Gps:
if len(row) < 2:
raise ValueError(f"GPS row must have 2 values (longitude,latitude). Got: {row}")
lon = float(row[0])
lat = float(row[1])
return Gps(longitude=lon, latitude=lat)