Research | Test couchdb/pouchdb as a replacement for the current db backend

[idncsk]

Canvas was originally using LevelDB as its main in-process DB, later RocksDB and currently LMDB .. for reasons ..

As we are moving to a more distributed, server-client architecture where a canvas-server instance will most likely be sitting either in a DC, and/or a beefy local workstation and/or on your NAS, we should start looking into some good sync libraries.

Canvas is meant to be a local/offline-first app and there are many good reasons for that, but you may also want to make your global context tree (with all indexes) available remotely so that you can get your work-life-balance trashed again by continuing your work seamlessly cross-device while traveling from office to your home for example.

With couchdb and its JS incarnation pouchdb,

• you get a lot of the sync heavy-lifting for free!
• master-master replication!
• it uses leveldb when running under nodejs!
• easy browser sync (could simplify our browser extension madness a lot)
• Could simplify all the extension work (hyper, obsidian)
• Definitely some other positive things!

Then again,

• roaring bitmap indexes are stored in binary format, attachments for blob storage in pouch/couchdb look ugly
• CouchDB leaves a lot to be desired in terms of features(then again, there are almost none with lmdb)
• Don't remember why by I revisited this combo at least 2x over the last year+ and always returned to LMDB (but maybe it was just laziness 👍 )

References
[0] https://pouchdb.com/
[1] https://github.com/pouchdb/pouchdb-server
[2] https://couchdb.apache.org/