Make this work between two PouchDBs

[BigBlueHat]

It's not dissimilar to this approach using transform-pouch: http://stackoverflow.com/a/35805152/507169

However, it'd be handy to do this with a single command. Maybe:

dbA.migrateTo(dbB, function(doc) {
  if ('foo' in doc) return

  doc.foo = 'bar'
  return [doc]
}).then(...);

Maybe it's already possible and I just missed something. 😉

Thanks for making so much awesomeness!
🎩

[jo]

Yes, this is a good idea and might be very useful.

Its not possible atm but I think it won't require that much work. I'd happily accept a pull :)

[stuartpb]

I was just thinking about this in pouchdb-community/transform-pouch#37 and pouchdb-community/transform-pouch#38, and I think, unless I'm missing something, it's significantly dissimilar to an incoming transformation on migration.

A migration using this plugin will (I'm assuming) perform several put operations to update, each of which creates a new revision of the document that will be reflected if and when the database receiving the migration is replicated back to the original database (and, of course, with this, the migrations will be present in the original database - one of the reasons one would want to do migration only within the context of replication, to preserve the original data); a migration using transforms on incoming / outgoing data will consist of changes with no record of having been made, potentially leading to all kinds of trouble should the two worlds of document ever meet.