refactor downloader module

src/smodex/__init__.py

+from smodex import downloader
 from smodex import sm_anomaly
 from smodex import sm_climatology
-from smodex import sm_downloader
 from smodex import version
 from smodex import visual_sma_ts
 
 
-__all__ = ["sm_anomaly", "sm_climatology", "sm_downloader", "visual_sma_ts", "version"]
+__all__ = ["sm_anomaly", "sm_climatology", "downloader", "visual_sma_ts", "version"]

src/smodex/downloader.py

+"""
+    Soil Moisture Downloader: Configured to download datasets from the Climate Data Store
+    Downloads hourly soil moisture datasets for full year
+"""
+
+import argparse
+import json
+import logging
+import os
+import sys
+
+import numpy as np
+import pandas as pd
+
+import cdsapi
+
+
+logger = logging.getLogger(__name__)
+logger.setLevel(logging.INFO)
+formatter = logging.Formatter("%(asctime)s [%(levelname)s] %(message)s")
+stream_handler = logging.StreamHandler(sys.stdout)
+stream_handler.setFormatter(formatter)
+logger.addHandler(stream_handler)
+
+
+api_client = cdsapi.Client()
+
+
+def cds_downloader(start_date: str, end_date: str, conf_path: str, download_path: str) -> None:
+    """Downloads specified variables (e.g. volumetric soil water content) detailed in a
+    config file from ERA5 Climate Data Store for a specified time range (start and end date)
+
+    Args:
+        start_date (str): initial date to start downloading datasets from e.g. '2001-01-01'
+        end_date (str): last date to stop downloading datasets for e.g. '2045-12-31'
+        conf_path (str): directory to CDS API configuration json file e.g. \
+            configs/download_conf.json
+        download_path (str): directory to save the downloaded datasets in e.g. era_sm/
+    """
+
+    with open(conf_path) as file:
+        conf = json.load(file)
+
+    date_ranges = pd.date_range(start=start_date, end=end_date)
+    year_ranges = np.unique([date.year for date in date_ranges])
+
+    for yr in year_ranges:
+        conf["year"] = yr
+        logger.info(f"downloading ERA5 Soil Moisture from CDS API for {yr}")
+        if not os.path.exists(download_path):
+            os.makedirs(download_path)
+        api_client.retrieve(
+            "reanalysis-era5-single-levels", conf, download_path + f"ERA5_SM_{yr}.nc"
+        )
+        logger.info(f"Downloaded soil moisture now available at {download_path+f'ERA5_SM_{yr}.nc'}")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description="Downloads soil moisture datasets from start date \
+            to end date from ERA5 Climate Data Store"
+    )
+
+    parser.add_argument(
+        "start_date",
+        type=str,
+        help="initial date to start \
+                                     downloading from e.g. 2001-01-01",
+    )
+
+    parser.add_argument(
+        "end_date",
+        type=str,
+        help="end date to stop \
+                                     downloading datasets from e.g. 2030-12-31",
+    )
+
+    parser.add_argument(
+        "conf_path",
+        type=str,
+        help="directory to download configuration json file e.g. configs/download.json",
+    )
+
+    parser.add_argument(
+        "download_path",
+        type=str,
+        help="directory to save the \
+                        downloaded datasets e.g. sm_downloaded/",
+    )
+
+    args = parser.parse_args()
+
+    cds_downloader(args.start_date, args.end_date, args.conf_path, args.download_path)

src/smodex/sm_downloader.py

-"""
-    Soil Moisture Downloader: Configured to download datasets from the Climate Data Store
-    Downloads hourly soil moisture datasets for full year
-"""
-import argparse
-import json
-import logging
-import os
-import sys
-
-import numpy as np
-import pandas as pd
-
-import cdsapi
-
-
-logger = logging.getLogger(__name__)
-logger.setLevel(logging.INFO)
-formatter = logging.Formatter("%(asctime)s [%(levelname)s] %(message)s")
-stream_handler = logging.StreamHandler(sys.stdout)
-stream_handler.setFormatter(formatter)
-logger.addHandler(stream_handler)
-
-
-c = cdsapi.Client()
-
-
-def era5_sm_downloader(year: str, download_path: str, depth: list, area: list) -> None:
-    """downloader from ERA5 API"""
-
-    variables = []
-    for dep in depth:
-        variables.append(f"volumetric_soil_water_layer_{dep}")
-
-    c.retrieve(
-        "reanalysis-era5-single-levels",
-        {
-            "product_type": "reanalysis",
-            "variable": variables,
-            "year": int(year),
-            "month": [
-                "01",
-                "02",
-                "03",
-                "04",
-                "05",
-                "06",
-                "07",
-                "08",
-                "09",
-                "10",
-                "11",
-                "12",
-            ],
-            "day": [
-                "01",
-                "02",
-                "03",
-                "04",
-                "05",
-                "06",
-                "07",
-                "08",
-                "09",
-                "10",
-                "11",
-                "12",
-                "13",
-                "14",
-                "15",
-                "16",
-                "17",
-                "18",
-                "19",
-                "20",
-                "21",
-                "22",
-                "23",
-                "24",
-                "25",
-                "26",
-                "27",
-                "28",
-                "29",
-                "30",
-                "31",
-            ],
-            "time": [
-                "00:00",
-                "06:00",
-                "12:00",
-                "18:00",
-            ],
-            "area": area,
-            "format": "netcdf",
-        },
-        download_path + f"ERA5_SM_{year}.nc",
-    )
-
-
-def downloader(
-    start_date: str, end_date: str, download_path: str, api: str, depth: list, area: list
-) -> None:
-    """download"""
-
-    date_ranges = pd.date_range(start=start_date, end=end_date)
-    date_ranges = [date.year for date in date_ranges]
-    years = np.unique(date_ranges)
-
-    for yr in years:
-        if api == "era5":
-            logger.info(f"Initiating downloading of ERA5 Soil Moisture for {yr}")
-            if not os.path.exists(download_path):
-                os.makedirs(download_path)
-            era5_sm_downloader(yr, download_path, depth, area)
-            logger.info(f"Downloaded ERA5 Soil Moisture for {yr}")
-
-
-if __name__ == "__main__":
-    # command line option
-    parser = argparse.ArgumentParser(
-        description="Downloads soil moisture \
-                                     datasets from start date to end date"
-    )
-    parser.add_argument(
-        "start_date",
-        type=str,
-        help="initial date to start \
-                                     downloading from e.g. 1990-01-01",
-    )
-    parser.add_argument(
-        "end_date",
-        type=str,
-        help="end date to stop \
-                                     downloading datasets from e.g. 2030-12-31",
-    )
-    parser.add_argument("api", type=str, help="download portal API e.g. era5, lpdaac, etc.")
-    parser.add_argument(
-        "-a",
-        "--area",
-        type=json.loads,
-        help="bounding box area for downloading \
-                         datasets e.g. [50.775, 2.775, 42.275, 18.025]",
-    )
-    parser.add_argument(
-        "-d",
-        "--depth",
-        type=json.loads,
-        help="volumetric \
-                        soil moisture depths e.g. [1, 2, 3, 4]",
-    )
-    parser.add_argument(
-        "path",
-        type=str,
-        help="directory to save the \
-                        downloaded datasets e.g. /sm_downloaded/",
-    )
-
-    args = parser.parse_args()
-
-    downloader(args.start_date, args.end_date, args.path, args.api, args.depth, args.area)