Comment by lukevp | Hacker News Reader

Comment by lukevp | Hacker News Reader

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Thanks for the reply, that’s the RFC I was referring to, and it’s great that that’s being reviewed! If you look back on the history of couchdb on HN for example, the lack of document based ACLs continues to come up as a serious limitation of couchdb. Because it speaks http(s) natively, it is a perfect db that can be used directly in place of a lot of the rest of your stack if your use case is a MBaaS. I see couch primarily positioned to compete with firebase firestore, but the perspective I see from maintainers is that it should be competing with mongodb instead (especially with the integration of mango queries and the push to put proxies in front of it.)

I feel that moving further in this direction to make couch a competitor at the DB later will be the death of couchdb in the long run, because it is removing the only real advantage it has over its peers, which is https based replication to the browser and between peer DBs, and the fact that it’s built on Erlang and can handle replication to many peers with ease. If you make us proxy and wrap the Erlang app in our crappy (excuse the language) business layers like Java and C# to build the proxy ACLs against a separate DB, you’ve totally covered up the huge benefit of the safety and concurrency of Erlang in handling the replication to endpoints for us.

Curious why they suggest a reverse proxy. It may be a holdover from a time before Erlang SSL got so many improvements? Heroku moved SSL termination to Erlang from ELB's and saw great improvements, plus they released a useful lib https://github.com/heroku/snit

I suppose it could be related to their use of mochiweb still for the web layer. Maybe they'll add on HTTP/2 eventually and no longer recommend a reverse proxy.

There are alternatives for HTTP/1.1 and HTTP/2 in Erlang, like Elli (http/1) https://github.com/elli-lib/elli and Chatterbox (http/2) library https://github.com/joedevivo/chatterbox

This is an architecture I use a lot. The reverse proxy is there to implement the replication, having your application understand the replication protocol is a big ask. Instead, your app takes http requests, handles the ones it is supposed to, and forwards database requests directly to (c|p)ouchdb (after checking auth)

https://github.com/daleharvey/noted/blob/master/index.js is a very simple example of how it can work

Right, but if your application is just a straight proxy that’s stripping out a bearer jwt or something to validate, you can’t control which documents are being synced. So you have to have 1) some understanding of the underlying protocol so you can parse the request and reject it based on user if that user does not have read/write access to the db, or 2) replicate your authorization code into couchdb with users and db permissions, at which point you have the same db per user issue (or lack thereof) plus you now have 2 user stores and 2 layers. Once this gets sufficient complexity and you try to architect something non trivial (eg. User a owns write access to document b but shares read only access to document b to user C) you end up praying to god you built the protocol parsing just right or you might accidentally let users arbitrarily write to each other’s documents.

I acknowledge that this is the same issue in a traditional dbms, but it doesn’t try to handwave away this complexity from you. It doesn’t show examples on their site about how easy replication is to set up only to be betrayed later After you’ve already integrated and marveled at the couchdb sync performance when you can’t build real permissions and would’ve been better off using Postgres and getting a bigger community and ACID/CP. and let’s be honest, almost every app is gonna need a rdbms at least for transactional data anyway (we know you’re not storing stripe billing records in your couchdb) so then the question becomes, is the sync protocol even good enough anymore to warrant using couchdb?

We really shouldn't be writing our own authentication layers (or anything security-related for that matter) unless necessary.

Case in point, this example code has a massive security issue that allows anyone to impersonate without tokens if there is an active authentication request open. Hopefully no one has used this example code to build a production system that has real user data.

This is a perfect example of why this should really be part of CouchDB/PouchDB itself and not something each person must write themselves. This should be solved once, solved right, vetted by the community, and be easy to fall into a pit of success.

I really like CouchDB and PouchDB as a product, but this insistence that this is the right path is really holding you guys back.

You're probably write about writing your own authentication layer but it still shouldn't be part of CouchDB or PouchDB. A better solution is for some OSS project to build a standard proxy that applies the document level authorization that everyone is asking for. No reason for it to be built-in.

I would agree if couchdb wasn't positioning itself as being exposed directly on the internet. If CouchDB is meant to be proxied behind another system / auth stack, then why does it have CORS support and cookie auth built in?

Both of those features are purely a client-side concern and exist because the original intent of CouchDB was real-time replication to browsers. Otherwise the proxy could do the CORS as well as the authentication and CouchDB would only require an http-level authentication pattern (like basic auth).

Having said that, I do agree that this should be compartmentalized and the end user should be able to pick and choose what features they want to allow, but I don't think that this should continue to be a separate concern that everyone is building themselves, it should be a first-party solution.

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