Updating

What it is

wdx update installs a newer release over the one you have, stopping and starting the daemon around it, and keeps the old binary, a backup of the database and the config file, so that --rollback brings them back. Terminals and agents keep running through it.

Try it

Without a flag it only looks:

$ wdx update
update available: wdx 0.3.0 -> 0.4.0 (stable channel)
  run wdx update --apply
$ wdx update --apply
==> downloading wdx 0.4.0
==> checking that it runs on the settings
==> stopping the daemon
==> backing up wdx 0.3.0, the database and the settings
==> installing wdx 0.4.0
==> starting the daemon
updated wdx 0.3.0 -> 0.4.0
  schema:   16 -> 27
  rollback: wdx update --rollback goes back to 0.3.0
$ wdx version
wdx 0.4.0 (31f674f)
daemon 0.4.0 (31f674f)

Changed your mind:

$ wdx update --rollback
==> stopping the daemon
==> backing up wdx 0.4.0, the database and the settings
==> installing wdx 0.3.0
==> starting the daemon
rolled back wdx 0.4.0 -> 0.3.0
  schema:   27
  database: kept

How it behaves

• Channels. stable by default, or dev for the development builds released between stable ones: the update.channel setting, or --channel for once. --version installs a given release.
• All or nothing. If any step fails, the old binary, database and config file are put back and the daemon starts on the old binary.
• Settings. The new release writes the config file anew: your values stay, its new settings are listed, and keys it no longer has are commented out at the end. A rollback puts the file back as it was.
• The database on rollback. Most releases only add to the database, so the older version goes on using it and nothing is lost. When a release since the update changed it in a way the older one cannot read, the backup taken at the update is restored, losing what changed since; you are asked first, or --discard-changes and --cancel answer.
• One previous version is kept, so a rollback goes back one step only.
• Running terminals keep the holder that started them, on the old version, until they start again; the daemon and new terminals run the new one.
• The changelog says what each release changed, and what it breaks.

Commands

Command	What it does
wdx update	Show whether a newer wdx is released, install it or roll it back
wdx version	Print the version of wdx and of the daemon