Setting userProject from NIO FileSystemProvider

[ryan-williams]

I'm happy to see that requester-pays support was just added!

afaict, I can't set the userProject in a CloudStorageFileSystemProvider that gets instantiated via the Java NIO FileSystemProvider machinery, which uses Class.newInstance() to invoke the nullary constructor:

import java.net.URI;
import java.nio.file.Paths;
import java.nio.file.Files;
Files.newDirectoryStream(Paths.get(new URI("gs://<bucket>")))

throws:

com.google.cloud.storage.StorageException: Bucket is requester pays bucket but no user project provided.
  at com.google.cloud.storage.spi.v1.HttpStorageRpc.translate(HttpStorageRpc.java:220)
  at com.google.cloud.storage.spi.v1.HttpStorageRpc.list(HttpStorageRpc.java:347)
  at com.google.cloud.storage.StorageImpl$8.call(StorageImpl.java:299)
  …

Is there a way to set the user-project, other than as a ctor param?

• an environment variable would seem easiest
  • afaict there's no standard mechanism for doing that across GCS libraries in various languages
  • perhaps it's still ok to add one here
• a setter would help a bit
  • I'll be mainly using it from hammerlab/path-utils, where I (unfortunately) have code to reach into the installedProviders and modify the providers for a given URI scheme
  • a setter would at least save me from a second reflection hack to reach

[yihanzhen]

You could set the userProject in CloudStorageConfiguration as is in the tests. Please let us know if that's not what you want.

[ryan-williams]

Thanks for that pointer @hzyi-google; that helped, but I still needed #3504.

CloudStorageFileSystemProvider checks its instance var userProject to determine whether to set that parameter when calling storage.get, but that was never being set from [the config passed to setDefaultCloudStorageConfiguration].

[yihanzhen]

Thanks for the clarification and contribution! I added a few comments in the pull request, can you take a look please?

[ryan-williams]

jfyi: I published a fork of the google-cloud-nio module with this merged at org.lasersonlab:google-cloud-nio:0.55.2-alpha; I think the PR is awaiting review, but no rush on my end 😄