---
description: >-
  Help developers to move from v2 to v3. Please read carefully and integrate the
  following breaking changes to ensure a smooth update.
---

# Upgrade to v3

{% hint style="warning" %}
Please be sure of your agent type and version and pick the right documentation accordingly.
{% endhint %}

{% tabs %}
{% tab title="Node.js" %}
{% hint style="danger" %}
This is the documentation of the `forest-express-sequelize` and `forest-express-mongoose` Node.js agents that will soon reach end-of-support.

`forest-express-sequelize` v9 and `forest-express-mongoose` v9 are replaced by [`@forestadmin/agent`](https://docs.forestadmin.com/developer-guide-agents-nodejs/) v1.

Please check your agent type and version and read on or switch to the right documentation.
{% endhint %}
{% endtab %}

{% tab title="Ruby on Rails" %}
{% hint style="success" %}
This is still the latest Ruby on Rails documentation of the `forest_liana` agent, you’re at the right place, please read on.
{% endhint %}
{% endtab %}

{% tab title="Python" %}
{% hint style="danger" %}
This is the documentation of the `django-forestadmin` Django agent that will soon reach end-of-support.

If you’re using a Django agent, notice that `django-forestadmin` v1 is replaced by [`forestadmin-agent-django`](https://docs.forestadmin.com/developer-guide-agents-python) v1.

If you’re using a Flask agent, go to the [`forestadmin-agent-flask`](https://docs.forestadmin.com/developer-guide-agents-python) v1 documentation.

Please check your agent type and version and read on or switch to the right documentation.
{% endhint %}
{% endtab %}

{% tab title="PHP" %}
{% hint style="danger" %}
This is the documentation of the `forestadmin/laravel-forestadmin` Laravel agent that will soon reach end-of-support.

If you’re using a Laravel agent, notice that `forestadmin/laravel-forestadmin` v1 is replaced by [`forestadmin/laravel-forestadmin`](https://docs.forestadmin.com/developer-guide-agents-php) v3.

If you’re using a Symfony agent, go to the [`forestadmin/symfony-forestadmin`](https://docs.forestadmin.com/developer-guide-agents-php) v1 documentation.

Please check your agent type and version and read on or switch to the right documentation.
{% endhint %}
{% endtab %}
{% endtabs %}

## Upgrade to v3

{% hint style="warning" %}
Please be aware that while Forest Admin make every effort to ensure that our platform updates are broadly compatible and offer detailed instructions for upgrading, Forest Admin cannot guarantee that custom code developed by the developers will always be compatible with new versions of our software. This includes any custom modifications or extensions to core functionalities, such as method overrides or custom integrations. It is the responsibility of the developers to review and test their custom code to ensure compatibility with each new version. Our team provides comprehensive upgrade guides to assist in this process, but these cannot encompass the unique customizations that may be present in each customer's environment. Therefore, Forest Admin strongly recommend establishing a thorough testing protocol for your specific customizations to safeguard against potential issues during the upgrade process.
{% endhint %}

### Breaking changes

#### Cors configuration

Set CORS `credentials: true` if you're using custom CORS configuration. See [how to configure CORS headers](../../setup/configuring-cors-headers).

{% tabs %}
{% tab title="Rails" %}
We use the [Rack CORS](https://github.com/cyu/rack-cors) Gem for this purpose.

{% code title="Gemfile" %}
```ruby
# Gemfile
source 'https://rubygems.org'

# ...

gem 'forest_liana'
gem 'rack-cors'
```
{% endcode %}

{% code title="/config/application.rb" %}
```ruby
module LiveDemoRails
  class Application < Rails::Application
    # ...

    # For Rails 5, use the class Rack::Cors. For Rails 4, you MUST use the string 'Rack::Cors'.
    config.middleware.insert_before 0, Rack::Cors do
      allow do
        origins 'app.forestadmin.com'
        resource '*',
          headers: :any,
          methods: :any,
          expose: ['Content-Disposition'],
          credentials: true
      end
    end
  end
end
```
{% endcode %}
{% endtab %}
{% endtabs %}

#### Global smart action

Smart actions defined as follows `global: true` will no longer be considered as global.

Please now use `type: 'global'`.

{% tabs %}
{% tab title="Rails" %}
**Before**

{% code title="lib/forest_liana/collections/product.rb" %}
```ruby
class Forest::Product
  include ForestLiana::Collection

  collection :Product

  action 'Import data',
    global: true

  # ...
end
```
{% endcode %}

**After**

{% code title="lib/forest_liana/collections/product.rb" %}
```ruby
class Forest::Product
  include ForestLiana::Collection

  collection :Product

  action 'Import data',
    type: 'global'

  # ...
end
```
{% endcode %}
{% endtab %}
{% endtabs %}

#### Schema versioning

On server start - _only in development environments_ - the agent will generate a `.forestadmin-schema.json` file reflecting your **Forest Admin schema**.

If you change your models or database, Forest Admin will automatically load a new schema to keep the layout up to date.

{% hint style="danger" %}
**Do not edit this file**. It will be automatically generated on server start **only in development environments**.

This file **must be deployed** for any remote environment (staging, production, etc.), as it will be used to generate your Forest Admin UI.
{% endhint %}

{% hint style="info" %}
**Version this file.** It will give you more visibility on the changes detected by Forest Admin.
{% endhint %}

In the following example, we have added two fields on the `invoices` table:

* `emailSent`
* `quadernoId`

Versioning the`.forestadmin-schema.json` file allows you to easily visualize the changes.

![.forestadmin-schema.json versioning example](https://2014605362-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LR7SWfEwsNtj_ZiSkSA%2F-LcecOC6sl4pvNT7gLKI%2F-LcecRPYz9T0g_e16FWT%2Fversioning.png?alt=media\&token=ded5a007-ccc7-4dd9-82ee-f939cf667a9f)

### Changelogs

This release note covers only the major changes. To learn more, please refer to the changelogs in our different repositories:

* [Rails changelog](https://github.com/ForestAdmin/forest-rails/blob/master/CHANGELOG.md#release-300---2019-04-22)
