asf_search

Python wrapper for the ASF SearchAPI

import asf_search as asf

results = asf.granule_search(['ALPSRS279162400', 'ALPSRS279162200'])
print(results)

wkt = 'POLYGON((-135.7 58.2,-136.6 58.1,-135.8 56.9,-134.6 56.1,-134.9 58.0,-135.7 58.2))'
results = asf.geo_search(platform=[asf.PLATFORM.SENTINEL1], intersectsWith=wkt, maxResults=10)
print(results)

Install

In order to easily manage dependencies, we recommend using dedicated project environments via Anaconda/Miniconda or Python virtual environments.

asf_search can be installed into a conda environment with

conda install -c conda-forge asf_search

or into a virtual environment with

python3 -m pip install asf_search

To install pytest/cov packages for testing, along with the minimal packages:

python3 -m pip install asf_search[test]

Usage

Full documentation is available at https://docs.asf.alaska.edu/asf_search/basics/

Programmatically searching for ASF data is made simple with asf_search. Several search functions are provided:

• geo_search() Find product info over an area of interest using a WKT string
• granule_search() Find product info using a list of scenes
• product_search() Find product info using a list of products
• search() Find product info using any combination combination of search parameters
• stack() Find a baseline stack of products using a reference scene
• Additionally, numerous constants are provided to ease the search process

Additionally, asf_search support downloading data, both from search results as provided by the above search functions, and directly on product URLs. An authenticated session is generally required. This is provided by the ASFSession class, and use of one of its three authentication methods:

• auth_with_creds('user', 'pass')
• auth_with_token('EDL token')
• auth_with_cookiejar(http.cookiejar)

That session should be passed to whichever download method is being called, can be re-used, and is thread safe. Examples:

results = asf_search.granule_search([...])
session = asf_search.ASFSession()
session.auth_with_creds('user', 'pass')
results.download(path='/Users/SARGuru/data', session=session)

Alternately, downloading a list of URLs contained in urls and creating the session inline:

urls = [...]
asf_search.download_urls(urls=urls, path='/Users/SARGuru/data', session=ASFSession().auth_with_token('EDL token'))

Also note that ASFSearchResults.download() and the generic download_urls() function both accept a processes parameter which allows for parallel downloads.

Further examples of all of the above can be found in examples/

Development

Branching

Instance	Branch	Description, Instructions, Notes
Stable	stable	Accepts merges from Working and Hotfixes
Working	master	Accepts merges from Features/Issues and Hotfixes
Features/Issues	topic-*	Always branch off HEAD of Working
Hotfix	hotfix-*	Always branch off Stable

For an extended description of our workflow, see https://gist.github.com/digitaljhelms/4287848

Enable Logging

We use standard the standard logging in our package for output.

Heres a basic example for hooking into it with your application:

import asf_search as asf
import logging
ASF_LOGGER = logging.getLogger("asf_search")
formatter = logging.Formatter('[ %(asctime)s (%(name)s) %(filename)s:%(lineno)d ] %(levelname)s - %(message)s')

# Get output to the console:
stream_handle = logging.StreamHandler()
stream_handle.setFormatter(formatter)
ASF_LOGGER.addHandler(stream_handle)
# If you want it write to a file too:
file_handle = logging.FileHandler('MyCustomApp.log')
file_handle.setFormatter(formatter)
ASF_LOGGER.addHandler(file_handle)
# Only see messages that might affect you
ASF_LOGGER.setLevel(logging.WARNING)
# Test if the logger throws an error, you see it as expected:
ASF_LOGGER.error("This is only a drill. Please do not panic.")
# Should output this:
# [ 2023-01-17 10:04:53,780 (asf_search) main.py:42 ] ERROR - This is only a drill. Please do not panic.

For more configure options on logging, please visit their howto page.

Testing

After installing asf-search's test requirement (see INSTALL section above) you can run the test suite locally. Run the following command from your terminal in the root project directory:

python3 -m pytest -n auto .

Tests should be written to relevant subfolder & files in /tests

The test suite uses the pytest-automation pytest plugin which allows us to define and re-use input for test cases in the yaml format. Test cases are written to files in tests/yml_tests/, and reusable resources for those tests tests/yml_tests/Resources/.

tests:
- Test Nisar Product L1 RSLC: # this is a test case
    product: NISAR_L1_PR_RSLC_087_039_D_114_2005_DHDH_A_20251102T222008_20251102T222017_T00407_N_P_J_001.yml # this file should be in `tests/yml_tests/Resources/`. See other yml files in the folder to see how you might structure the yml object
    product_level: L1

- Test Nisar Product L2 GSLC: # this is another test case
    product: NISAR_L2_PR_GSLC_087_039_D_112_2005_DHDH_A_20251102T221859_20251102T221935_T00407_N_F_J_001.yml
    product_level: L2

We can create the mapping from our yaml test cases in tests/pytest-config.yml, which will be used to call the desired python function in tests/pytest-managers.py

In tests/pytest-config.yml:

- For running ASFProduct tests:
    required_keys: ['product', 'product_level'] # the keys the test case requires
    method: test_NISARProduct # the python function in pytest-managers.py that will be called
    required_in_title: Test Nisar Product # (OPTIONAL) will only run test cases defined with `Test Nisar Product` in the name, so the above two test cases would be run with our tests.

In tests/pytest-managers.py:

def test_NISARProduct(**args) -> None: # Must match the name in pytest-config.yml like above for `method`
    """
    Test asf_search.search.baseline_search.stack_from_product, asserting stack returned is ordered
    by temporalBaseline value in ascending order
    """
    test_info = args['test_info'] # these are the args defined in our test case (in this case [`product`, `product_level`])
    product_level = test_info['product_level']

    product_yml_file = test_info['product']
    product = get_resource(product_yml_file) # `get_resources()` is a helper function that can read yml files from `tests/yml_tests/Resources/`
    

    # `run_[test_name]` should contain your actual test logic
    run_test_NISARProduct(product, product_level)