Copernicus S1 GRD IndexError: list index out of range

[fjoudelat]

Hello,
First of all thanks for the work !
It seems that I cannot open Sentinel-1 products obtained from Copernicus.
I have Python 3.13, xsar 2025.6.12, xarray-safe-s1 2025.9.25 via conda-forge
The issue seems to be related to the xml mapping of the manifest.
Here is a Copernicus product to replicate the issue : file transfer
Thanks in advance 🙏

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\xsar\utils.py", line 101, in wrapper
    result = f(*args, **kwargs)
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\xsar\xsar.py", line 67, in open_dataset
    sar_obj = Sentinel1Dataset(*args, **kwargs)
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\xsar\sentinel1_dataset.py", line 130, in __init__
    self.sar_meta = BlockingActorProxy(Sentinel1Meta, dataset_id)
                    ~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\xsar\utils.py", line 539, in __init__
    self._actor = self._cls(*args, **kwargs)
                  ~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\xsar\utils.py", line 101, in wrapper
    result = f(*args, **kwargs)
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\xsar\sentinel1_meta.py", line 49, in __init__
    self.reader = Sentinel1Reader(name)
                  ~~~~~~~~~~~~~~~^^^^^^
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\safe_s1\reader.py", line 68, in __init__
    self.manifest_attrs = self.xml_parser.get_compound_var(
                          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        self.manifest, "safe_attributes_slcgrd"
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\safe_s1\xml_parser.py", line 159, in get_compound_var
    result[key] = self.get_var(xml_file, path, describe=describe)
                  ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\safe_s1\xml_parser.py", line 104, in get_var
    result = func(result)
  File "C:\ProgramData\miniconda3\envs\copernicus\Lib\site-packages\safe_s1\sentinel1_xml_mappings.py", line 29, in <lambda>
    scalar = lambda x: x[0]
                       ~^^^
IndexError: list index out of range

[fjoudelat]

The error seems to come from xml_parser.py
result = self.xpath(xml_file, xpath)
returns an empty list [], hence the out of range error
It happens for these values of xpath :

xml_file = 'manifest.safe'
xpath = '//metadataSection/metadataObject/metadataWrap/xmlData/safe:processing/safe:resource/safe:processing/safe:resource[@role="AUX_CAL"]/@name'
'//metadataSection/metadataObject/metadataWrap/xmlData/safe:processing/safe:resource/safe:processing/safe:resource[@role="AUX_PP1"]/@name'
'//metadataSection/metadataObject/metadataWrap/xmlData/safe:processing/safe:resource/safe:processing/safe:resource[@role="AUX_INS"]/@name'

EDIT: The error goes away when I edit the xml path. The relevant tags are burried a safe:processing/safe:resource/ step deeper in my manifest.safe.

"aux_cal": (
    scalar,
    '//metadataSection/metadataObject/metadataWrap/xmlData/safe:processing/safe:resource/safe:processing/safe:resource/safe:processing/safe:resource[@role="AUX_CAL"]/@name',
),
"aux_pp1": (
    scalar,
    '//metadataSection/metadataObject/metadataWrap/xmlData/safe:processing/safe:resource/safe:processing/safe:resource/safe:processing/safe:resource[@role="AUX_PP1"]/@name',
),
"aux_ins": (
    scalar,
    '//metadataSection/metadataObject/metadataWrap/xmlData/safe:processing/safe:resource/safe:processing/safe:resource/safe:processing/safe:resource[@role="AUX_INS"]/@name',
),

[agrouaze]

Hi @fjoudelat ,
thanks for the issue.
In the end, it is a problem with the lib or with the specific product you tried to open?
Can you share the name of the product?