Dropbox Datastore API Alternatives

Haha... yep. I was shocked when Parse made that announcement. :)

I have since switched to a new data storage solution where everything gets stored in SQLite and I sync the SQLite databases between devices using Dropbox.

I sure hope Dropbox doesn't shut down their main API. :)

Is syncing latest versions of SQLite db really the best option? 

I thought I'll just try normal file sync and figure out how the linking would work.

For my situation and what I'm trying to accomplish, it seems to be a good option. 

Any special logic your applying (if you don't mind sharing)?

All the syncing is done via SQL queries, so it's very custom. Here's how it works:

Step 1: Download the remote Dropbox SQLite file.

Step 2: Open the local SQLite file and the remote SQLite file and attach them so they can be queried simultaneously.

Step 3: Perform queries that add new records from the remote database to the local SQLite database, delete records marked as deleted, and update records which have a newer "updated" time (I have a timestamp column)

Step 4: Once the local database reflects all the changes, upload the local database and replace the remote Dropbox SQLite file

I switched to Firebase as soon as the announcement was made and its a perfect substitute, I would definitely suggest you take a look!

(and no, I'm not in any way affiliated with them, just really love their product :D)

@Clifton: Thanks for sharing

I'm really struggling to find a good way to switch away from Datastores. I have a simple Notes with Tags system. 

At first I thought, I'll jump to the usual "creating" raw files in an app folder on Dropbox wherein each DBRecord is now a text file. But I have thousands of those records (short notes). I don't know how efficient it would actually be. I'm gonna test this out though. 

To get back to your syncing I'm assuming:

Every "Remote db" is actually the fully updated "local db" of  some device that ran a session prior to the latest. 

OR

Is the Remote DB a set of queries of "transactions" that occurred in "a" particular session. and perhaps your storing a differently named "truth" db file separately on dropbox?

One more question Is:

Are you uploading the dbFile at every "save" call?

Yes, the local and remote DBs are the same structure, they just get compared for new/changed/deleted records with each sync. I don't keep a log of transactions, I just compare the databases.

And yes, each sync requires a download and an upload of the database file.

So the downsides:

1. It's "expensive" to sync (download time, database comparison processor power, upload time)

But the upsides are many:

1. I can use SQLite queries to dissect and display the data how I need to.
2. Troubleshooting for customers is easy because they can send me their whole database and I can run queries in it and inspect the data.
3. SQLite is available to both mobile and web platforms
4. All the data is available offline

If you don't need to do any querying against your note records, then I would recommend you take a look at Apple's CloudKit (unless you need to do an Android app). You might also look at Firebase.

Your right. I'm gonna try your approach and stick with Dropbox (for now atleast). 

Thankfully, I also used SQLite as my local storage and kept DBDatastore for syncing. Only need to figure out backup and sync architecture. (which is ... so not easy).

Oh well, thanks for help :)

I've started using Firebase too and so far find it very powerful. Certainly saves a lot of time compared to rolling your own server/sync solution. It would be nice if we had more certainty about the future of these hosted sync services but for now I think I'll stick with it. I built a very basic sync engine in Python and Core Data for my first app but ran into many problems with my users' data not syncing correctly. It's great just not having to worry about sync at all and focus on actually building the core features of the app.