Feature request: influx inspect -export should dump WAL files

[mark-rushakoff]

Feature Request

influx inspect -export currently does not read or export data from WAL files. It only reads .tsm files. In its current form, it is unable to extract data-at-rest that has not yet been snapshotted to TSM, which means not all of the data is recoverable with the influx inspect tool.

[jwilder]

These would need to be appended after the TSM files so that replaying them inserts them in the correct order.

[jwilder]

I have branch started here: https://github.com/influxdata/influxdb/tree/jw-tsm-wal-inspect

[corylanou]

The first question we need to answer is should a shard export include the wal file?

If not, do we add an option like -include-wal when exporting (or leave it as a separate command like this commit does: 6e60cbb), or have both options?

Additionally, do we want the ability to export an entire directory (retention policy) as well? The functionality for this has been mostly completed already in 2ccf4bd

//cc @dgnorton @jwilder

[jwilder]

Yes. Export of a shard should include the wal segments automatically as they are part of the data stored in the shard.