Hi.

As far as I know, the only way for updating the Metadata of a file stored using GridFS is working directly on the fs.files collection using the GetCollection method on a istance of ‎MongoDatabase.

I think that having a specific method on GridFSBucket for updating the Metadata of a file could be an interesting improvement.

I would suggest to create an UpdateMetadata method in the GridFSBucket class. This method should take the id of the file and an UpdateDefinition<TDocument> field.

Let me know if you think that this could be a good improvement. If you think so, then I would like to implement this new method.

Best regards.

Marco