GCS NIO readAttributes returns CloudStorageObjectAttributes for directory like objects

[tomcham]

Thanks for stopping by to let us know something could be better!

Please include as much information as possible:

Environment details

• google-cloud-java version(s): google-cloud-nio:0.69.0-alpha

Steps to reproduce

1. In the GCS UI within a bucket, press create folder button and create a folder called dir
2. Upload a file within dir call this fileA

Code snippet

    FileSystem fs = ....
    Files.walkFileTree(fs.getPath("dir") new SimpleFileVisitor<Path>() {
      @Override
      public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
        System.out.println(file);
        return FileVisitResult.CONTINUE;
      }

Any additional information below

The GCS UI creates a 0 byte object called dir/ This causes readAttributes to return https://github.com/googleapis/google-cloud-java/blob/v0.69.0/google-cloud-clients/google-cloud-contrib/google-cloud-nio/src/main/java/com/google/cloud/storage/contrib/nio/CloudStorageFileSystemProvider.java#L765, which prevents further traversal of objects within that directory.

Does it make sense to do a check like https://github.com/googleapis/google-cloud-java/blob/v0.69.0/google-cloud-clients/google-cloud-contrib/google-cloud-nio/src/main/java/com/google/cloud/storage/contrib/nio/CloudStorageFileSystemProvider.java#L756 usePseudoDirectories is enabled and it is a 0 byte object?

I saw this related merged PR https://github.com/googleapis/google-cloud-java/pull/3775/files by @jean-philippe-martin

[jean-philippe-martin]

Yes, what the UI does is rather surprising. As discussed in this GitHub issue we end up with both a file and a directory that have the same name.

I didn't see your fix before writing mine, sorry. I think it makes sense for NIO to report the underlying truth, namely that both the file and the directory exist.

[jean-philippe-martin]

Reopen: there is some tool out there that now creates 11-byte files with a trailing slash to pretend directories exist, and this breaks the merged fix.

See this bug report for an example.

[jean-philippe-martin]

OK no need to reopen, let's use #5203 instead.