Does graphula support persistent-mongoDB?

[codygman]

I think the answer is no. I ran into this error:

/home/cody/smurf/test/ITProTV/Database/Particle/Models/HostSpec.hs:49:27-51: error:
    • Couldn't match type ‘Database.MongoDB.Query.MongoContext’
                     with ‘Database.Persist.Sql.Types.Internal.SqlBackend’
        arising from a use of ‘node’
    • In a stmt of a 'do' block:
        Entity _ hostVal <- node @Host.Host () mempty
      In the second argument of ‘($)’, namely
        ‘do Entity _ hostVal <- node @Host.Host () mempty
            Host.hostBio hostVal
              `Test.shouldBe` Just (Gluon.HostBio "Some Texan.")’
      In a stmt of a 'do' block:
        runGraphulaT Nothing _runDB
          $ do Entity _ hostVal <- node @Host.Host () mempty
               Host.hostBio hostVal
                 `Test.shouldBe` Just (Gluon.HostBio "Some Texan.")

I'm assuming this means that you must be using the SqlBackend which persistent-mongoDB does not use.

Any way to make this work, ideas on how feasible implementing it is, etc?

[eborden]

Yes, it is currently bound to SqlBackend, though I'm not sure if that is from convenience or necessity. @cdparks do you see a viable path to abstracting persistent backends away and removing the dependence on SqlBackend?

[cdparks]

@eborden there's a few layers of abstraction around what a "backend" is in persistent, so I suspect this is possible, but I'll need to study it