Add reader for Landsat L1 data

[simonrp84]

This PR adds a reader for Landsat collection 2 level 1 data. It has been tested on Landsat 8 and 9 data and doesn't yet support older satellites in the landsat series.

Right now this is a draft as I haven't added tests, but the reader itself should be fully-functional.

• Tests added
• Fully documented

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.11%. Comparing base (15a0800) to head (dce15c3).
Report is 148 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2904      +/-   ##
==========================================
+ Coverage   96.05%   96.11%   +0.05%     
==========================================
  Files         370      377       +7     
  Lines       54334    54931     +597     
==========================================
+ Hits        52191    52796     +605     
+ Misses       2143     2135       -8     

Flag	Coverage Δ
behaviourtests	3.95% <0.00%> (-0.04%)	⬇️
unittests	96.20% <100.00%> (+0.05%)	⬆️

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[coveralls]

Pull Request Test Coverage Report for Build 11374003337

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 355 of 355 (100.0%) changed or added relevant lines in 2 files are covered.
• 88 unchanged lines in 10 files lost coverage.
• Overall coverage increased (+0.04%) to 96.209%

---

Files with Coverage Reduction	New Missed Lines	%
satpy/composites/config_loader.py	2	94.12%
satpy/tests/reader_tests/test_hrit_base.py	3	97.67%
satpy/readers/seadas_l2.py	3	96.97%
satpy/readers/msi_safe.py	4	98.41%
satpy/tests/reader_tests/modis_tests/_modis_fixtures.py	5	98.38%
satpy/composites/init.py	6	95.05%
satpy/readers/aapp_l1b.py	8	89.89%
satpy/readers/hdfeos_base.py	14	92.78%
satpy/utils.py	19	92.15%
satpy/readers/hrit_base.py	24	85.16%

Totals
Change from base Build 10814739875:	0.04%
Covered Lines:	53034
Relevant Lines:	55124

---

💛 - Coveralls

[mraspaud]

Nice job, I appreciate the comprehensive tests! A few suggestions inline.

[mraspaud]

pytest's tmp_pathis the way to go (gets cleaned up automatically also).

Also we usually have fixtures for test/synthetic files.

[simonrp84]

Unfortunately I don't know how fixtures work, so will be unable to add that. I'll change tmp_paththough.

[pdebuyl]

For temporary files, I used pytest fixtures in the modis reader.

Here, you could have something similar to:

@pytest.fixture(scope="session")
def oli_tirs_l1_tif_samplefiles(tmpdir_factory) -> list[str]:
    """Create a set of OLI TIRS landsat L1 files."""
    path_1 =  str(tmpdir_factory.mktemp("oli_tirs_l1_tif").join("LC08_L1GT_026200_20240502_20240513_02_T2_MTL.xml"))
    with open(path_1, "w") as f:
      f.write(metadata_text)
    path_2 =  str(tmpdir_factory.mktemp("oli_tirs_l1_tif").join("LC08_L1GT_026200_20240502_20240513_02_T2_B4.TIF"))
    return [path_1, path_2, ...]

Then, to use it in a test:

def some_test(self, oli_tirs_l1_tif_samplefiles):
    scn = satpy.Scene(reader="oli_tirs_l1_tif", oli_tirs_l1_tif_samplefiles)

(where some_test is a member of the TestOLITIRSL1 class) will create the files on the fly.

I hope this helps to facilitate using the fixtures if you want to go that way. It is a bit annoying at first but then I found it convenient as you can write several tests that use the sample data files with really low effort.

[pdebuyl]

Regarding the failing tests, the sza on disk contains nans sometimes :-/

I don't know enough about the geotiff writer to comment but this seems to be the root cause

[simonrp84]

Regarding the failing tests, the sza on disk contains nans sometimes :-/

I don't know enough about the geotiff writer to comment but this seems to be the root cause

I think it's because the array I was generating ran from 0->10000. Have changed it locally to 1->10000 and haven't seen the error pop up again! Forgot that 0 was the fill value...

[mraspaud]

LGTM