How to define and use a custom ID generator?

By default, Kinto uses UUID4 as id for its records. In some cases, it might not be what you want. But you’re not out of luck, there is a way to configure Kinto to use a different id_generator than the default one.

Let’s define a “name generator”, which will output 8 random characters (uppercase or lowercase).

import random
import string

from import generators

class NameGenerator(generators.Generator):

    regexp = r'^[a-zA-Z0-9-_]{8}$'

    def __call__(self):
        ascii_letters = ('abcdefghijklmopqrstuvwxyz'
        alphabet = ascii_letters + string.digits + '-_'
        letters = [random.choice(ascii_letters + string.digits)]
        letters += [random.choice(alphabet) for x in range(7)]
        return ''.join(letters)

Note that you actually need to define both the generator and the validator, which can be provided as a regexp.


The id generator should be random enough to avoid collisions.

The random approach here serves the purpose of this tutorial, but for a production ready implementation, have a look at dylang/shortid for example.

Enable in configuration

Okay, once we’ve got this new generator, we can put it in a file named, and then configure the Kinto server to use this generator to actually generate the record IDs.

In your config/kinto.ini configuration file, set the kinto.id_generator setting:

kinto.id_generator = name_generator.NameGenerator

And then run your server as usual

$ kinto --ini config/kinto.ini start

Now, if you try to generate a new record, you should have the new ID used, well done!

$ echo '{"data": {"yeah": "oh"}}' | http POST http://localhost:8888/v1/buckets/default/collections/tasks/records --auth user:pass
HTTP/1.1 201 Created
Access-Control-Expose-Headers: Retry-After, Content-Length, Alert, Backoff
Content-Length: 171
Content-Type: application/json; charset=UTF-8
Date: Thu, 25 Feb 2016 22:13:20 GMT
Server: waitress

    "data": {
        "id": "fm64GtdA",
        "last_modified": 1456438400719,
        "yeah": "oh"
    "permissions": {
        "write": [


Currently the configuration of the custom generator applies to every resources (buckets, groups, collections, records). This tiny limitation can easily be fixed, don’t hesitate to get in touch with us!

Kinto.js client

The offline-first client Kinto/kinto.js can also be configured to generate custom ids. See its documentation for more details.