I've saved a spark data frame to cloud object storage into a Watson Studio project's bucket:
staging
.write
.mode("overwrite")
.option("header", "true")
.csv(cos.url('all.csv', 'myproject-bucket'))
I would the resulting folder to be show up in the project assets.
Initially, I tried using project-lib but from the documentation it appears that you have to have a file like object which means bringing all the data back to the driver node and if I do that, I run out of memory.
You can create a connection from Watson Studio to COS and publish the files.
Steps