engine kwargs dictionaries are modified in place

[malmans2]

What happened?

earthkit.data modifies engine kwargs in place, causing unexpected side effects in downstream code.

What are the steps to reproduce the bug?

import earthkit.data

dataset = "reanalysis-era5-pressure-levels"
request = {
    "product_type": ["reanalysis"],
    "variable": ["geopotential"],
    "year": ["2024"],
    "month": ["03"],
    "day": ["01"],
    "time": ["13:00"],
    "pressure_level": ["1000"],
    "data_format": "grib",
}
kwargs = {"squeeze": True}
ek_ds = earthkit.data.from_source("cds", dataset, **request)
xr_ds = ek_ds.to_xarray(engine="cfgrib", xarray_open_dataset_kwargs=kwargs)
assert kwargs == {"squeeze": True}

Version

v0.13.5

Platform (OS and architecture)

Darwin MacBook-Pro-di-Bopen.local 24.3.0 Darwin Kernel Version 24.3.0: Thu Jan 2 20:24:24 PST 2025; root:xnu-11215.81.4~3/RELEASE_ARM64_T6030 arm64

Relevant log output

AssertionError                            Traceback (most recent call last)
Cell In[3], line 17
     15 ek_ds = earthkit.data.from_source("cds", dataset, **request)
     16 xr_ds = ek_ds.to_xarray(engine="cfgrib", xarray_open_dataset_kwargs=kwargs)
---> 17 assert kwargs == {'squeeze': True}

AssertionError:

Accompanying data

No response

Organisation

B-Open / EQC

[sandorkertesz]

@malmans2 Thank you for reporting this issue. Will be fixed in the next hotfix release.

[sandorkertesz]

Fixed in #671

[sandorkertesz]

0.13.8 has been released with a fix for this issue.

[malmans2]

Thanks!