frankinspace / l2ss-py

Level 2 subsetter with Harmony integration

l2ss-py

develop:
main:

Harmony service for subsetting L2 data. l2ss-py supports:

• Spatial subsetting
• Temporal subsetting
• Variable subsetting

If you would like to contribute to l2ss-py, refer to the contribution document.

How to test l2ss-py locally

Unit tests

There are comprehensive unit tests for l2ss-py. The tests can be run as follows:

poetry run pytest -m "not aws and not integration" tests/

You can generate coverage reports as follows:

poetry run pytest --junitxml=build/reports/pytest.xml --cov=podaac/ --cov-report=html -m "not aws and not integration" tests/

l2ss-py script

You can run l2ss-py on a single granule without using Harmony. In order to run this, the l2ss-py package must be installed in your current Python interpreter

$ l2ss-py --help                                                                                                                    
usage: run_subsetter.py [-h] [--bbox BBOX BBOX BBOX BBOX]
                        [--variables VARIABLES [VARIABLES ...]]
                        [--min-time MIN_TIME] [--max-time MAX_TIME] [--cut]
                        input_file output_file

Run l2ss-py

positional arguments:
  input_file            File to subset
  output_file           Output file

optional arguments:
  -h, --help            show this help message and exit
  --bbox BBOX BBOX BBOX BBOX
                        Bounding box in the form min_lon min_lat max_lon
                        max_lat
  --variables VARIABLES [VARIABLES ...]
                        Variables, only include if variable subset is desired.
                        Should be a space separated list of variable names
                        e.g. sst wind_dir sst_error ...
  --min-time MIN_TIME   Min time. Should be ISO-8601 format. Only include if
                        temporal subset is desired.
  --max-time MAX_TIME   Max time. Should be ISO-8601 format. Only include if
                        temporal subset is desired.
  --cut                 If provided, scanline will be cut

For example:

l2ss-py /path/to/input.nc /path/to/output.nc --bbox -50 -10 50 10 --variables wind_speed wind_dir ice_age time --min-time '2015-07-02T09:00:00' --max-time '2015-07-02T10:00:00' --cut

Running Harmony locally

In order to fully test l2ss-py with Harmony, you can run Harmony locally. This requires the data exists in UAT Earthdata Cloud.

1. Set up local Harmony instance. Instructions here
2. Add concept ID for your data to services.yml
3. Execute a local Harmony l2ss-py request. For example:

   localhost:3000/YOUR_COLLECTION_ID/ogc-api-coverages/1.0.0/collections/all/coverage/rangeset?format=application%2Fx-netcdf4&subset=lat(-10%3A10)&subset=lon(-10%3A10)&maxResults=2