#!/usr/bin/env python3 """Download ArcGIS data and convert to Parquet.""" # Run it with: # uv run download_arcgis_data.py import time import zipfile import httpx import polars as pl from pathlib import Path from tqdm import tqdm URL = "https://www.arcgis.com/sharing/rest/content/items/077631e063eb4e1ab43575d01381ec33/data" BASE_DATA_PATH = Path("./data_sources") BASE_DATA_PATH.mkdir(exist_ok=True) DOWNLOAD_PATH = BASE_DATA_PATH / "arcgis_data.zip" EXTRACT_PATH = BASE_DATA_PATH / "arcgis_extracted" PARQUET_PATH = BASE_DATA_PATH / "arcgis_data.parquet" MAX_RETRIES = 3 def download_with_progress(url: str, output_path: Path) -> None: """Download a file with progress bar and retry logic.""" for attempt in range(1, MAX_RETRIES + 1): try: with httpx.stream( "GET", url, follow_redirects=True, timeout=httpx.Timeout(30.0, read=None), ) as response: response.raise_for_status() # pyright: ignore[reportUnusedCallResult] total = int(response.headers.get("content-length", 0)) with ( open(output_path, "wb") as f, tqdm( total=total, unit="B", unit_scale=True, unit_divisor=1024, desc="Downloading", ) as pbar, ): for chunk in response.iter_bytes(chunk_size=8192): f.write(chunk) pbar.update(len(chunk)) return # Success except (httpx.ConnectError, httpx.ReadTimeout) as e: if attempt < MAX_RETRIES: wait = 2**attempt print(f"Attempt {attempt} failed: {e}. Retrying in {wait}s...") time.sleep(wait) else: raise def extract_zip(zip_path: Path, extract_path: Path) -> list[Path]: """Extract ZIP file and return list of extracted files.""" print("Extracting ZIP file...") extract_path.mkdir(exist_ok=True) with zipfile.ZipFile(zip_path, "r") as zf: zf.extractall(extract_path) return [extract_path / name for name in zf.namelist()] def find_data_file(extract_path: Path) -> Path: """Find the main data file (CSV, XLSX, or similar) in extracted files.""" # Look for common data file extensions for ext in ["*.csv", "*.xlsx", "*.xls", "*.json", "*.geojson"]: files = list(extract_path.rglob(ext)) if files: # Return the largest file if multiple found return max(files, key=lambda f: f.stat().st_size) raise FileNotFoundError(f"No data file found in {extract_path}") def convert_to_parquet(data_path: Path, parquet_path: Path) -> None: """Convert data file to Parquet using Polars.""" print(f"Converting {data_path.name} to Parquet...") suffix = data_path.suffix.lower() if suffix == ".csv": df = pl.read_csv(data_path, try_parse_dates=True) elif suffix in [".xlsx", ".xls"]: df = pl.read_excel(data_path) elif suffix in [".json", ".geojson"]: df = pl.read_json(data_path) else: raise ValueError(f"Unsupported file format: {suffix}") df.write_parquet(parquet_path, compression="zstd") print(f"Saved to {parquet_path}") print(f"Rows: {df.height:,}") print(f"Columns: {df.columns}") print(f"Original size: {data_path.stat().st_size / 1024**2:.1f} MB") print(f"Parquet size: {parquet_path.stat().st_size / 1024**2:.1f} MB") def main() -> None: if PARQUET_PATH.exists(): print(f"Parquet already exists at {PARQUET_PATH}, skipping") return if not DOWNLOAD_PATH.exists(): download_with_progress(URL, DOWNLOAD_PATH) else: print(f"File already exists at {DOWNLOAD_PATH}, skipping download") # Check if it's a ZIP file if zipfile.is_zipfile(DOWNLOAD_PATH): extracted_files = extract_zip(DOWNLOAD_PATH, EXTRACT_PATH) print(f"Extracted {len(extracted_files)} files") data_file = find_data_file(EXTRACT_PATH) else: # Not a ZIP, treat as direct data file data_file = DOWNLOAD_PATH convert_to_parquet(data_file, PARQUET_PATH) if __name__ == "__main__": main()