problem with dynamic bucket creation.

Hi everyone,
Is possible set the bucket name with the name of a record field, or tag?
Example

```

@type record_transformer
enable_ruby true
auto_typecast true

tenant ${record["attrs"]["tag"].split('|')[1]}

(...)

@type copy

@type s3
(...)
s3_bucket ${record["tenant"]}
(...)
```
I receved logs from diferents tenants and wish put each one in a bucket.
Tkz in advance!