We lost the nice context-stack [jobname][taskname][...] at the beginning
of each log line when switching to logrus.
Define some field names that define these contexts.
Write a human-friendly formatter that presents these field names like
the solution we had before logrus.
Write some other formatters for logfmt and json output along the way.
Limit ourselves to stdout logging for now.
Implement
* pruning on source side
* local job
* test subcommand for doing a dry-run of a prune policy
* use a non-blocking callback from autosnap to trigger the depending
jobs -> avoids races, looks saner in the debug log
Done:
* implement autosnapper that asserts interval between snapshots
* implement pruner
* job pull: pulling + pruning
* job source: autosnapping + serving
TODO
* job source: pruning
* job local: everything
* fatal errors such as serve that cannot bind socket must be more
visible
* couldn't things that need a snapshotprefix just use a interface
Prefixer() instead? then we could have prefixsnapshotfilter and not
duplicate it every time...
* either go full context.Context or not at all...? just wait because
community climate around it isn't that great and we only need it for
cancellation? roll our own?
How it works:
`zrepl stdinserver CLIENT_IDENTITY`
* connects to the socket in $global.serve.stdinserver.sockdir/CLIENT_IDENTITY
* sends its stdin / stdout file descriptors to the `zrepl daemon` process (see cmsg(3))
* does nothing more
This enables a setup where `zrepl daemon` is not directly exposed to the
internet but instead all traffic is tunnelled through SSH.
The server with the source job has an authorized_keys file entry for the
public key used by the corresponding pull job
command="/mnt/zrepl stdinserver CLIENT_IDENTITY" ssh-ed25519 AAAAC3NzaC1E... zrepl@pullingserver
