html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/pull/2492#issuecomment-431868326,https://api.github.com/repos/pydata/xarray/issues/2492,431868326,MDEyOklzc3VlQ29tbWVudDQzMTg2ODMyNg==,1217238,2018-10-22T15:26:24Z,2018-10-22T15:26:24Z,MEMBER,thanks @alexamici ,"{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,371514413
https://github.com/pydata/xarray/pull/2492#issuecomment-431425504,https://api.github.com/repos/pydata/xarray/issues/2492,431425504,MDEyOklzc3VlQ29tbWVudDQzMTQyNTUwNA==,1217238,2018-10-19T16:44:19Z,2018-10-19T16:44:32Z,MEMBER,"As someone who hasn't opened up a grib file for several years, I'm not in a good position to choose which backend to use by default. For now, I would be inclined to hold off on making a default choice (unless there is a clear consensus among other xarray devs/users) in favor of requiring users to be explicit. This is somewhat inline with the Zen of Python: ""In the face of ambiguity, refuse the temptation to guess.""

Probably the best user experience would be to raise an informative error suggesting the use of cfgrib or pynio when opening a grib but no engine is specified, e.g.,
```
>>> xarray.open_dataset('data.grib')
ValueError: cannot open GRIB files without explicitly setting engine='pynio'
or engine='cfgrib' in xarray.open_dataset()
```","{""total_count"": 3, ""+1"": 3, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,371514413
https://github.com/pydata/xarray/pull/2492#issuecomment-431166092,https://api.github.com/repos/pydata/xarray/issues/2492,431166092,MDEyOklzc3VlQ29tbWVudDQzMTE2NjA5Mg==,1217238,2018-10-18T21:15:10Z,2018-10-18T21:15:10Z,MEMBER,"Actually, thinking about this a little more, I'm not entirely sure it makes sense to fallback from using pynio to cfgrib. The problem is that these libraries may interpret GRIB files differently, e.g., with different variable names. It could make for a poor user experience for `open_dataset('mydata.grib')` to work differently when different dependencies are installed.

(please let me know if I'm mistaken here!)","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,371514413
https://github.com/pydata/xarray/pull/2492#issuecomment-431053815,https://api.github.com/repos/pydata/xarray/issues/2492,431053815,MDEyOklzc3VlQ29tbWVudDQzMTA1MzgxNQ==,1217238,2018-10-18T15:28:06Z,2018-10-18T15:28:06Z,MEMBER,"> The whole engine detection strategy looks a bit fragile as the .gz extension is recognised outside of _get_default_engine and the nested ifs and try / except blocks make the code poorly readable. I can add a bit of a refactor in this area if you think it is appropriate.

Agreed! Yes, this would be welcome.

I'm happy with this change, but it would be good to ensure we have test coverage. It looks like we currently don't have any unit tests, but I'm pretty sure the other code is exercised by integration tests. If you're up for adding unit tests for `_get_default_engine` that would be awesome.","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,371514413