https://github.com/citusdata/activerecord-multi-tenant
Rails/ActiveRecord support for distributed multi-tenant databases like Postgres+Citus
https://github.com/citusdata/activerecord-multi-tenant
activerecord citus multi-tenant rails
Last synced: about 1 month ago
JSON representation
Rails/ActiveRecord support for distributed multi-tenant databases like Postgres+Citus
- Host: GitHub
- URL: https://github.com/citusdata/activerecord-multi-tenant
- Owner: citusdata
- License: mit
- Created: 2016-09-10T00:05:34.000Z (almost 9 years ago)
- Default Branch: master
- Last Pushed: 2024-11-11T09:56:11.000Z (7 months ago)
- Last Synced: 2025-05-13T09:06:38.076Z (about 1 month ago)
- Topics: activerecord, citus, multi-tenant, rails
- Language: Ruby
- Homepage:
- Size: 686 KB
- Stars: 741
- Watchers: 48
- Forks: 105
- Open Issues: 39
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# activerecord-multi-tenant
[](https://github.com/citusdata/activerecord-multi-tenant/actions/workflows/active-record-multi-tenant-tests.yml) [](https://codecov.io/gh/citusdata/activerecord-multi-tenant) [ ](https://rubygems.org/gems/activerecord-multi-tenant)[ ](https://rubygems.org/gems/activerecord-multi-tenant) [](https://activerecord-multi-tenant.readthedocs.io/en/latest/?badge=latest)
Introduction Post: https://www.citusdata.com/blog/2017/01/05/easily-scale-out-multi-tenant-apps/
ActiveRecord/Rails integration for multi-tenant databases, in particular the open-source [Citus](https://github.com/citusdata/citus) extension for PostgreSQL.
Enables easy scale-out by adding the tenant context to your queries, enabling the database (e.g. Citus) to efficiently route queries to the right database node.
## Installation
Add the following to your Gemfile:
```ruby
gem 'activerecord-multi-tenant'
```
## Supported Rails versions
All Ruby on Rails versions starting with 6.0 or newer (up to 7.0) are supported.
This gem only supports ActiveRecord (the Rails default ORM), and not alternative ORMs like Sequel.
## Usage
It is required that you add `multi_tenant` definitions to your model in order to have full support for Citus, in particular when updating records.
In the example of an analytics application, sharding on `customer_id`, annotate your models like this:
```ruby
class PageView < ActiveRecord::Base
multi_tenant :customer
belongs_to :site
# ...
end
class Site < ActiveRecord::Base
multi_tenant :customer
has_many :page_views
# ...
end
```
and then wrap all code that runs queries/modifications in blocks like this:
```ruby
customer = Customer.find(session[:current_customer_id])
# ...
MultiTenant.with(customer) do
site = Site.find(params[:site_id])
site.update! last_accessed_at: Time.now
site.page_views.count
end
```
Inside controllers you can use a before_action together with set_current_tenant, to set the tenant for the current request:
```ruby
class ApplicationController < ActionController::Base
set_current_tenant_through_filter # Required to opt into this behavior
before_action :set_customer_as_tenant
def set_customer_as_tenant
customer = Customer.find(session[:current_customer_id])
set_current_tenant(customer)
end
end
```
## Rolling out activerecord-multi-tenant for your application (write-only mode)
The library relies on tenant_id to be present and NOT NULL for all rows. However,
its often useful to have the library set the tenant_id for new records, and then backfilling
tenant_id for existing records as a background task.
To support this, there is a write-only mode, in which tenant_id is not included in queries,
but only set for new records. Include the following in an initializer to enable it:
```ruby
MultiTenant.enable_write_only_mode
```
Once you are ready to enforce tenancy, make your tenant_id column NOT NULL and simply remove that line.
## Frequently Asked Questions
* **What if I have a table that doesn't relate to my tenant?** (e.g. templates that are the same in every account)
We recommend not using activerecord-multi-tenant on these tables. In case only some records in a table are not associated to a tenant (i.e. your templates are in the same table as actual objects), we recommend setting the tenant_id to 0, and then using MultiTenant.with(0) to access these objects.
* **What if my tenant model is not defined in my application?**
The tenant model does not have to be defined. Use the gem as if the model was present. `MultiTenant.with` accepts either a tenant id or model instance.
## Credits
This gem was initially based on [acts_as_tenant](https://github.com/ErwinM/acts_as_tenant), and still shares some code. We thank the authors for their efforts.
## License
Copyright (c) 2018, Citus Data Inc.
Licensed under the MIT license, see LICENSE file for details.