Migration Assistant ​

The Migration Assistant plugin imports an existing collection from another collection manager — Mylar3 or Kapowarr — by reading its database. Both apps store ComicVine volume ids, so every series maps exactly: no fuzzy matching, no wrong-volume surprises.

Admins get a Migrate entry in the sidebar's System area.

Migrating ​

1. Pick the source database — upload mylar.db (Mylar3) or Kapowarr.db (Kapowarr), or point at a path the server can read (e.g. a folder mounted into the container). Upload a copy, or stop the other app first.
2. Preview — the parsed series list, with anything already in your library marked and deselected. Optionally pick a target library.
3. Import — each series is added through the normal ComicVine path with live progress. Monitored/paused state carries over.

Finding the source database ​

The file is recognised by its tables, not its name — a Mylar3 database is the one with a comics table carrying a ComicID column, Kapowarr's has a volumes table with comicvine_id — so a copy you renamed still works. The upload accepts .db, .sqlite and .sqlite3, up to 512 MB; the uploaded copy is deleted as soon as the import finishes.

If the other app runs on the same host, the tidiest route is a read-only bind mount so BackIssue can read the database in place and can never write to it:

services:
  backissue:
    volumes:
      - /srv/mylar3/config:/import:ro

Then enter /import/mylar.db in the path box. The database is only ever opened read-only, but a database still being written to is a moving target — stop the other app first, or copy the file somewhere and upload the copy.

What carries over ​

Brought across:

• The series itself, by its ComicVine volume id — an exact match, never a guess. Title and year are shown in the preview so you can recognise rows.
• Monitored or paused, as a monitoring policy: a monitored series arrives set to All issues, a paused one to Off.
• The library you choose in the preview (or your default one).

Left behind — these have no equivalent in the source database, or aren't read at all:

• Reading history and progress. A migrated collection starts unread.
• Custom folder names and paths. The source's folder is read for the preview only and never applied; your files are found by scanning your own library folders.
• Download history, queues, blocklists and failed grabs.
• Aliases and alternate search names — add any you need per series.
• Per-series settings such as format, quality or provider preferences.
• Issue-level state. What you own comes from the scan; picks and skips start empty.

Two more details worth knowing: rows with no ComicVine id (a series the other app never matched) are skipped — there's nothing exact to map them to — and duplicate rows for the same volume collapse into one, preferring a monitored copy.

After the import ​

1. Scan — run System → Tools → Scan entire library so your files on disk attach to the imported series.
2. Mop up — anything the scan couldn't place goes through Sidebar → Import, which matches folders and ComicInfo.xml tags; the Library's Unmatched and Incomplete filters show what's still outstanding.
3. Set monitoring — paused series arrive Off. Use the Library's bulk bar to set the policy you actually want, then look at the Wanted page before anything is fetched.

Safety ​

• Nothing is downloaded automatically — migrating hundreds of series never queues a single grab. Review your library first, then fetch what's missing.
• Re-running is safe — already-imported series are skipped. If the import halts on a ComicVine rate limit, run it again later and it continues.
• Your files on disk are never touched; the migration only creates series entries and tracking state.