Is it possible to have Centralised Logging for ElasticBeanstalk Docker apps?

Perhaps an AWS Lambda function is applicable?

Write some javascript that dumps all notifications, then see what you can do with those.

After an object is written, you could rename it within the same bucket?

Or notify your own log-management service about the creation of a new object?

Lots of possibilities there...

I've started using Sumologic for the moment. There's a free trial and then a free tier (500mb /day, 7 day retention). I'm not out of the trial period yet and my EB app does literally nothing (it's just a few HTML pages serve by Nginx in a docker container. Looks like it could get expensive once you hit any serious amount of logs though.

It works ok so far. You need to create an IAM user that has access to the S3 bucket you want to read from and then it sucks the logs over to Sumologic servers and does all the processing and searching over there. Bit fiddly to set up, but I don't really see how it could be simpler and it's reasonably well-documented.

It lets you provide different path expressions with wildcards, then assign a "sourceCategory" to those different paths. You then use those sourceCategories to filter your log searching to a specific type of logging.

My plan long-term is to use something like your solution 3, but this got me going in very short order so I can move on to other things.

You can use a Multicontainer environment, sharing the log folder to another docker container with the tool of your preference to centralize the logs, in our case we connected an Apache Flume to move the files to an HDFS. Hope this helps you with this.