Keep buffer of JdbcWriter after connection loss

[re-thc]

Hi, currently JDBCWriter will lose logs if a connection drops or before a connection is established.

Can a replay buffer be added to deal with these situations? i.e. check connection and reconnect if required, but do not "lose" these entries. Instead add it to a queue and write them again when connect is available.

[gabrielnasser]

Perhaps this could be done via the existing writing thread functionality by adding persistence to it? That way persistence can be enjoyed by any writer.

[re-thc]

There's a slight difference. If persistence happens across the board - where does this go? In a file or JDBC? Which becomes a circular problem. A global buffer would be good though - even for file so we can log before it opens.

I think slf4j does something similar with a substitute logger that gets initialized at the start and then swaps over once the real logger initializes.

[pmwmedia]

A pull request is welcome!

[pmwmedia]

Could be solved easily inside of JdbcWriter.java