How to enable BLOB-logging for a Node.js Api App on Azure?

I have a node.js api app on azure. I use bunyan to log every request to sdtout. How can I save and read the log files? I enabled BLOB-logging. The only thing that shows up in my storage is a bunch of csv-files. Here is an example:

| date                | level   | applicationName | instanceId | eventId            | pid   | tid | message
_______________________________________________________________________________________________________________________________________________________________
| 2017-05-17T14:21:15 | Verbose | myApp           | tae9d6     | 636306276755847146 | 13192 | -1  | SnapshotHelper::RestoreSnapshotInternal SUCCESS - File.Copy
| 2017-05-17T14:21:15 | Verbose | myApp           | tae9d6     | 636306276756784690 | 13192 | -1  | SnapshotHelper::RestoreSnapshotInternal SUCCESS - process

Where are my logs, that I printed to stdout?

via hendra