import csv import tempfile import zipfile from pathlib import Path from typing import Iterator import duckdb import requests import tqdm DUCKDB_SQL = ( """COPY (SELECT * FROM read_csv('%s', delim=';', AUTO_DETECT=TRUE)) TO '%s';""" ) def csv_iter(url: str, strip_header: bool = False) -> Iterator[list[str]]: """Download France AgriMer RNM CSV file from URL to output_file.""" r = requests.get(url, stream=True) with tempfile.TemporaryDirectory() as tmp_dir: tmp_zip_path = Path(tmp_dir) / "tmp.zip" # Copy the request content (a ZIP file) to a temporary file with tmp_zip_path.open("wb") as f: for chunk in r.iter_content(chunk_size=1024): if chunk: f.write(chunk) # Extract the name of the file we're interested in, there should be # only one file in the ZIP archive zip_file = zipfile.ZipFile(tmp_zip_path) zip_file_info = zip_file.infolist() if len(zip_file_info) != 1: raise ValueError("Expecting one file in zip") filename = zip_file_info[0].filename tmp_path = Path(tmp_dir) / filename # Extract the file to a temporary location with zip_file.open(filename, "r") as f_in: with tmp_path.open("wb") as f_out: while True: chunk = f_in.read(1024) if chunk == b"": break f_out.write(chunk) # The text is in ISO-8859-1 encoding # We strip spaces before/after all columns with open(tmp_path, "rt", encoding="ISO-8859-1", newline="") as f_in: csv_reader = csv.reader(f_in, delimiter=";") for i, row in enumerate(csv_reader): if strip_header and i == 0: continue yield [col.strip() for col in row] def generate_csv(output_path: Path, start_year: int, end_year: int) -> None: with open(output_path, "wt") as f_out: csv_writer = csv.writer(f_out, delimiter=";") for i in tqdm.tqdm(range(start_year, end_year + 1), desc="years"): url_template = f"https://visionet.franceagrimer.fr/Pages/OpenDocument.aspx?fileurl=Statistiques%2fmulti-filieres%2fcotations%20des%20produits%20frais%2fCOT-MUL-prd_RNM-A{i:02d}.zip&telechargersanscomptage=oui" for item in tqdm.tqdm( csv_iter(url_template, strip_header=(i != start_year)), desc="rows" ): csv_writer.writerow(item) def export_parquet(input_path: Path, output_path: Path) -> None: conn = duckdb.connect(":memory:") conn.execute(DUCKDB_SQL % (input_path, output_path)) OUTPUT_CSV_PATH = Path("COT-MUL-prd_RNM.csv") OUTPUT_PARQUET_PATH = Path("COT-MUL-prd_RNM.parquet") generate_csv(OUTPUT_CSV_PATH, start_year=0, end_year=24) export_parquet(OUTPUT_CSV_PATH, OUTPUT_PARQUET_PATH)