FunctionNotImplementedError when getting gridSpec from grib metadata

[HCookie]

What happened?

After updating to the new eccodes 2.41.0 running

data.metadata("gridSpec", default=None)

results in a FunctionNotImplementedError being raised from gribapi. In prior versions, the default was properly used, and returned.

What are the steps to reproduce the bug?

With eccodes==2.41.0

import earthkit.data as ekd
data = ekd.from_source('sample', 'aifs-single-mse-example.grib')

data.sel(param = '2t', step = 24).metadata("gridSpec", default=None)

Version

0.13.3

Platform (OS and architecture)

ATOS

Relevant log output

---------------------------------------------------------------------------
FunctionNotImplementedError               Traceback (most recent call last)
Cell In[4], line 1
----> 1 aifs.sel(param = '2t', step = 24).metadata("gridSpec", default=None)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/core/fieldlist.py:1297, in FieldList.metadata(self, *args, **kwargs)
   1295 result = []
   1296 for s in self:
-> 1297     result.append(s.metadata(*args, **kwargs))
   1298 return result

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/core/fieldlist.py:623, in Field.metadata(self, astype, remapping, patches, *keys, **kwargs)
    619 raise_on_missing = "default" not in kwargs
    620 default = kwargs.pop("default", None)
    622 r = [
--> 623     self._metadata.get(
    624         k,
    625         default=default,
    626         astype=kt,
    627         raise_on_missing=raise_on_missing,
    628         **kwargs,
    629     )
    630     for k, kt in zip(key, astype)
    631 ]
    633 if key_arg_type is str:
    634     return r[0]

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/core/metadata.py:119, in MetadataCacheHandler.cache_get.<locals>.wrapped(self, key, default, astype, raise_on_missing)
    116 if cache_id in self._cache:
    117     return self._cache[cache_id]
--> 119 v = func(self, key, default=default, astype=astype, raise_on_missing=raise_on_missing)
    120 self._cache[cache_id] = v
    121 return v

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/core/metadata.py:81, in MetadataAccessor.__call__.<locals>.wrapped(cls, key, *args, **kwargs)
     79 if key in self:
     80     return self.get(cls, key, *args, **kwargs)
---> 81 return func(cls, key, *args, **kwargs)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/readers/grib/metadata.py:384, in GribMetadata.get(self, key, default, astype, raise_on_missing)
    380     key = key[5:]
    382 key = _key_name(key)
--> 384 v = self._handle.get(key, ktype=astype, **_kwargs)
    386 # special case when  "shortName" is "~".
    387 if key == "shortName" and v == "~":

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/readers/grib/codes.py:155, in GribCodesHandle.get(self, name, ktype, **kwargs)
    152 elif name == "md5GridSection":
    153     return self.get_md5GridSection()
--> 155 return super().get(name, ktype, **kwargs)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/earthkit/data/utils/message.py:215, in CodesHandle.get(self, name, ktype, **kwargs)
    212         ktype = CodesHandle.KEY_TYPES[key_type_str]
    214 if "default" in kwargs:
--> 215     return super().get(name, ktype=ktype, **kwargs)
    216 else:
    217     # this will throw if name is not available
    218     return super()._get(name, ktype=ktype)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/eccodes/highlevel/message.py:68, in Message.get(self, name, default, ktype)
     56 """Get the value of a key
     57 
     58 Parameters
   (...)     65 ktype: type
     66     Request a specific type for the value. Overrides the suffix in ``name``"""
     67 try:
---> 68     return self._get(name, ktype=ktype)
     69 except KeyError:
     70     return default

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/eccodes/highlevel/message.py:53, in Message._get(self, name, ktype)
     51 if eccodes.codes_get_size(self._handle, name) > 1:
     52     return eccodes.codes_get_array(self._handle, name, ktype=ktype)
---> 53 return eccodes.codes_get(self._handle, name, ktype=ktype)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/gribapi/gribapi.py:2021, in grib_get(msgid, key, ktype)
   2019     result = grib_get_double(msgid, key)
   2020 elif ktype is str:
-> 2021     result = grib_get_string(msgid, key)
   2022 elif ktype is bytes:
   2023     result = grib_get_string(msgid, key)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/gribapi/gribapi.py:497, in grib_get_string(msgid, key)
    495 length_p = ffi.new("size_t *", length)
    496 err = lib.grib_get_string(h, key.encode(ENC), values, length_p)
--> 497 GRIB_CHECK(err)
    498 return _decode_bytes(values, length_p[0])

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/gribapi/gribapi.py:232, in GRIB_CHECK(errid)
    224 """
    225 Utility function checking the ecCodes error code and raising
    226 an error if that was set.
   (...)    229 @exception CodesInternalError
    230 """
    231 if errid:
--> 232     errors.raise_grib_error(errid)

File /etc/ecmwf/nfs/dh1_2_perm_a/ecm1947/venvs/earthkit/latest/lib/python3.12/site-packages/gribapi/errors.py:381, in raise_grib_error(errid)
    377 def raise_grib_error(errid):
    378     """
    379     Raise the GribInternalError corresponding to ``errid``.
    380     """
--> 381     raise ERROR_MAP[errid](errid)

FunctionNotImplementedError: Function not yet implemented

Accompanying data

No response

Organisation

ECMWF

[shahramn]

The gridSpec key is available but disabled. To enable it we have to make ecCodes depend on eckit (turning on the cmake option ENABLE_ECKIT_GEO). This is not ready yet so when you decode the gridSpec key, you get the error code GRIB_NOT_IMPLEMENTED

[sandorkertesz]

@shahramn, It comes down to the high level python API in ecCodes, which only returns the specified default value when there is a KeyError. Should not it do the same when the key is not implemented??

def get(self, name, default=None, ktype=None):
        """Get the value of a key

        Parameters
        ----------
        name: str
            Name of the key. Can be suffixed with ":str", ":int", or ":float" to
            request a specific type.
        default: any, optional
            Value if the key is not Found, or ``None`` if not specified.
        ktype: type
            Request a specific type for the value. Overrides the suffix in ``name``"""
        try:
            return self._get(name, ktype=ktype)
        except KeyError:
            return default

[shahramn]

OK. I can change the function to include FunctionNotImplementedError:

def raise_keyerror(name):
"""Make operations on a key raise a KeyError if not found"""
try:
yield
except (eccodes.KeyValueNotFoundError, eccodes.FunctionNotImplementedError):
raise KeyError(name)

[shahramn]

I have added a JIRA issue for ecCodes. See https://jira.ecmwf.int/browse/ECC-2072