Inake-xarray: AttributeError: 'list' object has no attribute 'startswith'

Question

I try to run this code, which ought to work...

import xarray as xr
import intake
import hvplot.xarray
import dask

catalog_url = 'https://raw.githubusercontent.com/hydrocloudservices/catalogs/main/catalogs/main.yaml'
cat=intake.open_catalog(catalog_url)

ds_era5l = cat.atmosphere.era5_land_reanalysis.to_dask()

the last line give me this error:

if path.startswith("file://"):
AttributeError: 'list' object has no attribute 'startswith'

The code is suppose to work as is... The complete traceback:

Traceback (most recent call last):
  File "E:\Windows programs\PyCharm Community Edition 2021.3.1\plugins\python-ce\helpers\pydev\_pydevd_bundle\pydevd_exec2.py", line 3, in Exec
    exec(exp, global_vars, local_vars)
  File "<input>", line 1, in <module>
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\intake_xarray\base.py", line 69, in to_dask
    return self.read_chunked()
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\intake_xarray\base.py", line 44, in read_chunked
    self._load_metadata()
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\intake\source\base.py", line 285, in _load_metadata
    self._schema = self._get_schema()
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\intake_xarray\base.py", line 18, in _get_schema
    self._open_dataset()
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\intake_xarray\xzarr.py", line 30, in _open_dataset
    self._mapper = get_mapper(self.urlpath, **self.storage_options)
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\fsspec\mapping.py", line 237, in get_mapper
    fs, urlpath = url_to_fs(url, **kwargs)
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\fsspec\core.py", line 387, in url_to_fs
    urlpath = fs._strip_protocol(url)
  File "E:\Anaconda3\envs\Data_Extraction\lib\site-packages\fsspec\implementations\local.py", line 207, in _strip_protocol
    if path.startswith("file://"):
AttributeError: 'list' object has no attribute 'startswith'

Answer 1

The code as given works fine for me, resulting in

<xarray.Dataset>
Dimensions:    (latitude: 701, longitude: 1171, time: 636240)
Coordinates:
  * latitude   (latitude) float64 85.0 84.9 84.8 84.7 ... 15.3 15.2 15.1 15.0
  * longitude  (longitude) float64 -167.0 -166.9 -166.8 ... -50.2 -50.1 -50.0
  * time       (time) datetime64[ns] 1950-01-01 ... 2022-07-31T23:00:00
Data variables:
    sd         (time, latitude, longitude) float32 dask.array<chunksize=(8760, 7, 7), meta=np.ndarray>
    t2m        (time, latitude, longitude) float32 dask.array<chunksize=(8760, 7, 7), meta=np.ndarray>
    tp         (time, latitude, longitude) float32 dask.array<chunksize=(8760, 7, 7), meta=np.ndarray>

It may be that you have an old version of intake-xarray or xarray. Ppassing a list of paths means using xr.open_mfdataset rather than xr.open_dataset, but this was not always supported for zarr. For this particular source, there is only one path, so expressing it as a list is not actually doing anything useful.