FAQ

How does Kinto compare to other solutions?

Before we started building our own data storage service, we took a look at what was already out there. Our initial intent was to use and possibly extend an existing community project rather than reinventing the wheel.

However, since none of the existing solutions we tried was a perfect fit for the problems we needed to solve, notably regarding fine-grained permissions, we started our own stack using the experience we gained from building Firefox Sync.

What follows is a comparison table showing how Kinto stacks up compared to some other projects in this space.

Project Kinto Parse Firebase CouchDB Kuzzle Remote-Storage Hoodie BrowserFS
Offline-first client  
Fine-grained permissions   ~   [1]  
Easy query mechanism [2] [3]  
Conflict resolution [4]  
Validation    
Revision history            
File storage    
Batch/bulk operations      
Changes stream    
Pluggable authentication       [5]
Pluggable storage / cache            
Self-hostable  
Decentralised discovery [6]            
Open source  
Language Python     Erlang Node.js Node.js [7] Node.js Node.js
[1]Currently, user plugin in Hoodie auto-approves users, but they are working on it.
[2]CouchDB uses Map/Reduce as a query mechanism, which isn’t easy to understand for newcomers.
[3]Remote Storage allows “ls” on a folder, but items are not sorted or paginated.
[4]Kinto uses the same mechanisms as Remote storage for conflict handling.
[5]Remote Storage supports OAuth2.0 implicit grant flow.
[6]Support for decentralised discovery is planned but not implemented yet.
[7]Remote Storage doesn’t define any default implementation (as it is a procol) but makes it easy to start with JavaScript and Node.js.

You can also read a longer explanation of our choices and motivations behind the creation of Kinto on our blog.

Can I encrypt my data?

Kinto server stores any data you pass to it, whether it’s encrypted or not. We believe encryption should always be done on the client-side, and we make it easy to use encryption in our Kinto.js client.

Is there a package for my Operating System?

No, but it’s a great idea. Maintaining packages for several platforms is time-consuming and we’re a small team.

Currently we make sure it’s easy to run with Docker or Python pip.

We also have a single-click deployment on some cloud providers.

Important

If you’d like to help us out by maintaining packages for your favourite OS, we’d be delighted to collaborate with you!

Why did you chose to use Python rather than X?

We love Python because it’s a concise & expressive language with powerful data structures & easy to learn, so it was an obvious choice for the development team.

In addition, the Operations team at Mozilla is comfortable with deploying and managing Python applications in production.

However, Python is just an implementation detail per se. Kinto is defined by an HTTP protocol that could be implemented in any language.

Is it Web Scale?

YES™. Have a look at the /dev/null backend. ;-)

Can I store files inside Kinto?

Yes, using the Kinto/kinto-attachment plugin.

I want to add business logic to Kinto!

We recommend that when you’re starting to build a Kinto-based application, you use Kinto as the back-end. You can use existing Kinto libraries to get up and running quickly.

If you eventually hit a point where you need more logic on the server side, you can build your own Kinto-esque service using the library in kinto.core. In this way, your service will inherit all the best practices and conventions that Kinto itself has, and you can seamlessly migrate.

How does Kinto authenticate users?

Kinto authentication system is pluggable and controlled from settings.

By default it ships with a very simple (but limited) Basic Authentication policy, which distinguishes users using the value provided in the header. In other words, any combination of user:password will be accepted. Kinto will encrypt them and determine a unique user id from them.

See also:

Note

We’d be delighted to add more built-in authentication methods into Kinto. Please reach out if you’re interested!

How to disable the permissions system (for development)?

By default, only the creator of the object has permission to write into it.

During development, it can be convenient to give the permission to write to any user.

Just create the bucket (or the collection) with system.Everyone in the write principals:

echo '{"permissions": {"write": ["system.Everyone"]}}' | \
    http PUT http://localhost:8888/v1/buckets/a-bucket --auth user:pass

I am seeing an Exception error, what’s wrong?

Have a look at the Troubleshooting section to see what to do.

If two users modify the same collection offline, how does that conflict get resolved?

There are three conflict resolution strategies:

  • SERVER_WINS: local changes are overridden by remote ones ;
  • CLIENT_WINS: remote changes are overriden by local one ;
  • MANUAL (default): handle them on your own.

There is, of course, a convenient API to handle conflict one by one https://kintojs.readthedocs.io/en/latest/api/#resolving-conflicts-manually

Would you recommend Redis or PostgreSQL?

You can use both of them:

  • Redis will let you start easily and you will have a database running in memory which

means your database should be smaller than your server RAM. It is a good solution for experimentation and you will also be able to use a Redis cluster to scale in production. * PostgreSQL is a good solution for a Kinto server and will let you use all the power of PostgreSQL and its tooling.

Do not hesitate to mix both if you can, for instance you can use PostgreSQL for the storage backend and Redis for the permission and cache backends.

What about aggregation/reporting around data, is Kinto ready for that?

No, and it will not. This is something that should be done on top of Kinto, with ElasticSearch for instance. In order to do this, you could listen to the events that Kinto triggers and send the data to your ElasticSearch cluster. There is a tutorial for that in the documentation.

Say I wanted to move all my Kinto data out of the database, would the best way to be via the backend?

It really depends on how you setup things, and what kind of data is there. One really simple way is to use the HTTP API. But depending the access you have to the user’s data, it might or might not be the solution you’re looking for. If you have access to the server, then doing a dump would get you the data out, but it won’t be in any documented format (it will be in an internal representation).

Nevertheless Kinto protocol is build in order for you to sync data. Therefore you can use the protocol to sync two databases.