From 663edde231af9ad4a782c5438027ef7f839806ea Mon Sep 17 00:00:00 2001
From: Jonas Gunz <himself@jonasgunz.de>
Date: Mon, 14 Oct 2024 02:23:10 +0200
Subject: package with python

---
 metchart/aggregator/dwd_icon.py | 149 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 149 insertions(+)
 create mode 100755 metchart/aggregator/dwd_icon.py

(limited to 'metchart/aggregator/dwd_icon.py')

diff --git a/metchart/aggregator/dwd_icon.py b/metchart/aggregator/dwd_icon.py
new file mode 100755
index 0000000..ed5c149
--- /dev/null
+++ b/metchart/aggregator/dwd_icon.py
@@ -0,0 +1,149 @@
+#!/usr/bin/env python3
+
+import requests
+import datetime
+import pytz
+import requests
+import os
+
+from multiprocessing import cpu_count
+from multiprocessing.pool import ThreadPool
+
+import subprocess
+
+import xarray as xr
+
+from . import misc
+
+BASE='https://opendata.dwd.de/weather/nwp'
+
+def get_current_run():
+    # we allow up to 3h of slack for DWD to upload the latest run
+    tz = pytz.timezone('UTC')
+    now = datetime.datetime.now(datetime.timezone.utc)
+    corrected = now - datetime.timedelta(hours=3)
+
+    run = int(corrected.hour / 6) * 6
+
+    return (f'{run:02d}', corrected.strftime('%Y%m%d'))
+
+def download_url(args):
+    url, dest = args
+    r = requests.get(url)
+    try:
+        with open(dest, 'wb') as f:
+            f.write(r.content)
+        print(f'Downloaded {dest}')
+    except Exception as e:
+        print(f'Failed to download {dest}:\n', e)
+
+def unpack_bz2(dest):
+    res = subprocess.run(['bzip2', '-df', dest])
+    if res.returncode != 0:
+        print(f'There was an error unpacking {dest}:', res.stderr)
+
+def download_dwd_gribs(
+        date, run, target, output, model, steps, model_long,
+        pressure_level_parameters, parameter_caps_in_filename,
+        single_level_parameters, pressure_levels
+):
+    misc.create_output_dir(output)
+
+    to_download = []
+
+    for step in steps:
+        step_str = f'{step:03d}'
+
+        for parameter in pressure_level_parameters:
+            parameter2 = parameter.upper() if parameter_caps_in_filename else parameter
+
+            for level in pressure_levels:
+                filename = f'{model_long}_regular-lat-lon_pressure-level_{date}{run}_{step_str}_{level}_{parameter2}.grib2.bz2'
+                URL = f'{BASE}/{model}/grib/{run}/{parameter}/{filename}'
+
+                to_download.append((URL, os.path.join(output, filename)))
+
+        for parameter in single_level_parameters:
+            parameter2 = parameter.upper() if parameter_caps_in_filename else parameter
+            filename = f'{model_long}_regular-lat-lon_single-level_{date}{run}_{step_str}_{parameter2}.grib2.bz2'
+            URL = f'{BASE}/{model}/grib/{run}/{parameter}/{filename}'
+
+            to_download.append((URL, os.path.join(output, filename)))
+
+
+    for _ in ThreadPool(cpu_count()).imap_unordered(download_url, to_download):
+        pass
+
+    print('Done Downloading. Uncompressing...')
+
+    for _ in ThreadPool(cpu_count()).imap_unordered(unpack_bz2, [dest for _, dest in to_download]):
+        pass
+
+    downloaded_gribs = [dest.removesuffix('.bz2') for _, dest in to_download]
+
+    res = subprocess.run(['grib_copy'] + downloaded_gribs + [target])
+    if res.returncode != 0:
+        print('grib_copy failed with: ', res.stderr)
+
+    res = subprocess.run(['rm', '-f'] + downloaded_gribs)
+    if res.returncode != 0:
+        print('rm failed with: ', res.stderr)
+
+def clean_output_dir(directory, target):
+    to_delete = [f for f  in os.listdir(directory) if os.path.isfile(os.path.join(directory, f))]
+    if target in to_delete:
+        del to_delete[to_delete.index(target)]
+
+    for f in to_delete:
+        os.unlink(os.path.join(directory, f))
+
+def load_data(name, output, description = None, clean = False, force_filename = None, **kwargs):
+    target = force_filename
+
+    if target is None:
+        run, date = get_current_run()
+        filename = f'{name}_{date}_{run}.grib2'
+        target = os.path.join(output, filename)
+
+        if not os.path.exists(target):
+            download_dwd_gribs(date, run, target, output, **kwargs)
+        else:
+            print(f'{target} already exists. Using the cached version.')
+
+        if clean:
+            clean_output_dir(output, filename)
+
+    # we drop heightAboveGround to allow 2m and 10m values to be merged down to one dataset
+    ds = xr.load_dataset(target, engine='cfgrib', drop_variables='heightAboveGround')
+
+    if description is not None:
+        ds.attrs['_description'] = description
+    return ds
+
+
+debug_config = {
+    'output':'dwd_icon-eu',
+    'model':'icon-eu',
+    'model_long':'icon-eu_europe',
+    'clean': True,
+    'parameter_caps_in_filename':True,
+    'pressure_level_parameters': [
+        't',
+        'relhum',
+        'u',
+        'v',
+        'fi',
+        'clc'
+    ],
+    'single_level_parameters': [
+        'pmsl',
+        't_2m',
+        'relhum_2m'
+    ],
+    'pressure_levels':[ 1000, 950, 925, 900, 875, 850, 825, 800, 775, 700, 600, 500, 400, 300, 250, 200, 150, 100 ],
+    'steps':[0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48]
+}
+
+if __name__ == '__main__':
+    load_data('test_icon_eu', **debug_config)
+
-- 
cgit v1.2.3