BUG:Cannot write as xlsx to GCS

[gfelot]

Code Sample, a copy-pastable example

output_path = f"gs://my_bucket/incidents/prediction/{ds}_incidents_result"
[...]
export_app.to_parquet(f"{output_path}.parquet")
export_app.to_excel(f"{output_path}.xlsx")

Problem description

I want to write the DF as a .parquet and a .xlsx file to a GCloud Storage bucket.
I launch the job in a K8S pod and I finally got the error message :

textPayload: "[Errno 2] No such file or directory: 'gs://my_bucket/incidents/prediction/2020-04-29_incidents_result.xlsx'

Next I change the to_excel -> to_csv and everything works as expected.

Do the to_excel can handle a path as gs://... ? Because it's the only issue I can see with that.

Output of pd.show_versions()

INSTALLED VERSIONS

commit : None
python : 3.7.7.final.0
python-bits : 64
OS : Linux
OS-release : 4.14.138+
machine : x86_64
processor :
byteorder : little
LC_ALL : C.UTF-8
LANG : C.UTF-8
LOCALE : en_US.UTF-8
pandas : 1.0.3
numpy : 1.18.1
pytz : 2020.1
dateutil : 2.8.1
pip : 20.0.2
setuptools : 46.1.3.post20200330
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : None
IPython : None
pandas_datareader: None
bs4 : None
bottleneck : None
fastparquet : None
gcsfs : 0.6.1
lxml.etree : None
matplotlib : None
numexpr : None
odfpy : None
openpyxl : 3.0.3
pandas_gbq : None
pyarrow : 0.15.1
pytables : None
pytest : None
pyxlsb : None
s3fs : None
scipy : 1.4.1
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : 1.3.0
xlsxwriter : None
numba : None

[twoertwein]

Since to_excel does currently not support writing to file objects it cannot support gs://. The two engines (openpyxl and xlsxwriter) that actually write the excel file also seem to want a file path and no file object.

Pandas would probably need to create a temporary file (I'm not sure whether pandas wants that), let the two engines write to it, read the content, and then write it to a file object to support gs://.

It is probably easier if the user calls to_excel with a local filename, reads the content, and then sends it to GCloud Storage.

edit: the excel backends seem to support file handles, so it should be possible to add support for google cloud storage.