Upload generate_rnm_ds.py

generate_rnm_ds.py

@@ -0,0 +1,80 @@
+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)