ipfs migration without starting the daemon

[RubenKelevra]

Currently, it seems to be impossible to do a migration (if necessary) without starting the daemon.

I'm a package maintainer and like script the migration after installation of the new package instead of running the migration on the first run of the daemon, which - as discussed earlier in a PR - might hit the timeout of systemd for starting a service.

I like to have an ipfs migrate --assume-yes or something like this for unattended migration while updating a package with a package manager.

It should return 0 if everything is fine, regardless if a migration was necessary or not.

[RubenKelevra]

This would solve #7269

[Stebalien]

You can run the migration tool: https://dist.ipfs.io/#fs-repo-migrations.
Or you can use ipfs update to update, which will apply the migration when it installs the new version.

[RubenKelevra]

You can run the migration tool: https://dist.ipfs.io/#fs-repo-migrations.

This requires quite some boiler plating, which is already integrated into the ipfs-binary, to be used by ipfs daemon --migrate. Would be nicer if the same functionality would be available without starting the daemon.

I think I would need to parse repo/fsrepo/migrations/migrations.go to fetch the right version. 🤔

Or you can use ipfs update to update, which will apply the migration when it installs the new version.

This doesn't work, I build the binary from git. So it makes no sense for me to fetch an older version.

[Stebalien]

Fair enough. I agree we should add an ipfs migrate command (probably ipfs repo migrate).

[Stebalien]

Command:

USAGE
  ipfs repo migrate - Apply any outstanding migrations to the repo.

SYNOPSIS
  ipfs repo migrate [--allow-downgrade]

OPTIONS
  --allow-downgrade bool - Allow downgrading to a lower repo version

This command should:

1. Refuse to run when the daemon is online. Add a line to the cmdDetailsMap in cmd/ipfs/ipfs.go specifying cannotRunOnDaemon: true.
2. Opens the repo (see how fsrepo.Open is used in cmd/ipfs/daemon.go).
3. Checks to see if there's a "needs migration" error (again, look at cmd/ipfs/daemon.go).
4. If so, runs migrate.RunMigration (see cmd/ipfs/daemon.go again).

[aschmahmann]

Note: state of this issue is that this is blocked pending a refactor of fs-repo-migrations (i.e. ipfs/fs-repo-migrations#98) such that we're using many binaries instead of one. This will mean that calling ipfs repo migrate will get and run each of the migration binaries required and become the primary way to do manual migrations.