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Authentication and permissions

Datasette does not require authentication by default. Any visitor to a Datasette instance can explore the full data and execute SQL queries.

Datasette's plugin system can be used to add many different styles of authentication, such as user accounts, single sign-on or API keys.

Actors

Through plugins, Datasette can support both authenticated users (with cookies) and authenticated API agents (via authentication tokens). The word "actor" is used to cover both of these cases.

Every request to Datasette has an associated actor value, available in the code as request.actor. This can be None for unauthenticated requests, or a JSON compatible Python dictionary for authenticated users or API agents.

The only required field in an actor is "id", which must be a string. Plugins may decide to add any other fields to the actor dictionary.

Plugins can use the :ref:`plugin_actor_from_request` hook to implement custom logic for authenticating an actor based on the incoming HTTP request.

Using the "root" actor

Datasette currently leaves almost all forms of authentication to plugins - datasette-auth-github for example.

The one exception is the "root" account, which you can sign into while using Datasette on your local machine. This provides access to a small number of debugging features.

To sign in as root, start Datasette using the --root command-line option, like this:

$ datasette --root
http://127.0.0.1:8001/-/auth-token?token=786fc524e0199d70dc9a581d851f466244e114ca92f33aa3b42a139e9388daa7
INFO:     Started server process [25801]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://127.0.0.1:8001 (Press CTRL+C to quit)

The URL on the first line includes a one-use token which can be used to sign in as the "root" actor in your browser. Click on that link and then visit http://127.0.0.1:8001/-/actor to confirm that you are authenticated as an actor that looks like this:

{
    "id": "root"
}

Checking permission

Datasette plugins can check if an actor has permission to perform an action using the :ref:`datasette.permission_allowed(...)<datasette_permission_allowed>` method. This method is also used by Datasette core code itself, which allows plugins to help make decisions on which actions are allowed by implementing the :ref:`plugin_permission_allowed` plugin hook.

Configuring permissions in metadata.json

You can limit who is allowed to view different parts of your Datasette instance using "allow" keys in your :ref:`metadata` configuration.

You can control the following:

  • Access to the entire Datasette instance
  • Access to specific databases
  • Access to specific tables and views
  • Access to specific :ref:`canned_queries`

If a user cannot access a specific database, they will not be able to access tables, views or queries within that database. If a user cannot access the instance they will not be able to access any of the databases, tables, views or queries.

Controlling access to an instance

Here's how to restrict access to your entire Datasette instance to just the "id": "root" user:

{
    "title": "My private Datasette instance",
    "allow": {
        "id": "root"
    }
}

To allow any of the actors with an id matching a specific list of values, use this:

{
    "allow": {
        "id": ["simon", "cleopaws"]
    }
}

This works for other keys as well. Imagine an actor that looks like this:

{
    "id": "simon",
    "roles": ["staff", "developer"]
}

You can provide access to any user that has "developer" as one of their roles like so:

{
    "allow": {
        "roles": ["developer"]
    }
}

Note that "roles" is not a concept that is baked into Datasette - it's more of a convention that plugins can choose to implement and act on.

If you want to provide access to any actor with a value for a specific key, use "*". For example, to spceify that a query can be accessed by any logged-in user use this:

{
    "allow": {
        "id": "*"
    }
}

These keys act as an "or" mechanism. A actor will be able to execute the query if any of their JSON properties match any of the values in the corresponding lists in the allow block.

Controlling access to specific databases

To limit access to a specific private.db database to just authenticated users, use the "allow" block like this:

{
    "databases": {
        "private": {
            "allow": {
                "id": "*"
            }
        }
    }
}

Controlling access to specific tables and views

To limit access to the users table in your bakery.db database:

{
    "databases": {
        "bakery": {
            "tables": {
                "users": {
                    "allow": {
                        "id": "*"
                    }
                }
            }
        }
    }
}

This works for SQL views as well - you can treat them as if they are tables.

Warning

Restricting access to tables and views in this way will NOT prevent users from querying them using arbitrary SQL queries.

If you are restricting access to specific tables you should also use the "allow_sql" block to prevent users from accessing

Controlling access to specific canned queries

To limit access to the add_name canned query in your dogs.db database to just the :ref:`root user<authentication_root>`:

{
    "databases": {
        "dogs": {
            "queries": {
                "add_name": {
                    "sql": "INSERT INTO names (name) VALUES (:name)",
                    "write": true,
                    "allow": {
                        "id": ["root"]
                    }
                }
            }
        }
    }
}

actor_matches_allow()

Plugins that wish to implement the same permissions scheme as canned queries can take advantage of the datasette.utils.actor_matches_allow(actor, allow) function:

from datasette.utils import actor_matches_allow

actor_matches_allow({"id": "root"}, {"id": "*"})
# returns True

The currently authenticated actor is made available to plugins as request.actor.

Permissions Debug

The debug tool at /-/permissions is only available to the :ref:`authenticated root user <authentication_root>` (or any actor granted the permissions-debug action according to a plugin).

It shows the thirty most recent permission checks that have been carried out by the Datasette instance.

This is designed to help administrators and plugin authors understand exactly how permission checks are being carried out, in order to effectively configure Datasette's permission system.

Permissions

This section lists all of the permission checks that are carried out by Datasette core, along with the resource if it was passed.

view-instance

Top level permission - Actor is allowed to view any pages within this instance, starting at https://latest.datasette.io/

view-database

Actor is allowed to view a database page, e.g. https://latest.datasette.io/fixtures

resource - string
The name of the database

view-database-download

Actor is allowed to download a database, e.g. https://latest.datasette.io/fixtures.db

resource - string
The name of the database

view-table

Actor is allowed to view a table (or view) page, e.g. https://latest.datasette.io/fixtures/complex_foreign_keys

resource - tuple: (string, string)
The name of the database, then the name of the table

view-query

Actor is allowed to view a :ref:`canned query <canned_queries>` page, e.g. https://latest.datasette.io/fixtures/pragma_cache_size

resource - string
The name of the canned query

execute-sql

Actor is allowed to run arbitrary SQL queries against a specific database, e.g. https://latest.datasette.io/fixtures?sql=select+100

resource - string
The name of the database

permissions-debug

Actor is allowed to view the /-/permissions debug page.