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Sessions

Sessions are used to make contextual API calls for either a shop (offline session) or a user (online session). This gem has ownership of session persistence.

Table of contents

Sessions

Types of access tokens (sessions)

  • Shop (offline access)
    • Access token is linked to the store
    • Meant for long-term access to a store, where no user interaction is involved
    • Ideal for background jobs or maintenance work
  • User (online access)
    • Access token is linked to an individual user on a store
    • Meant to be used when a user is interacting with your app through the web

Access token storage (session)

Shop (offline) token storage

⚠️ All apps must have a shop session storage, if you started from the Ruby App Template, it's already configured to have a Shop model by default.

If you don't already have a repository to store the access tokens:

  1. Run the following generator to create a shop model to store the access tokens
rails generate shopify_app:shop_model
  1. Configure config/initializers/shopify_app.rb to enable shop access token persistance:
config.shop_session_repository = 'Shop'
User (online) token storage

If your app has user interactions and would like to control permission based on individual users, you need to configure a User token storage to persist unique tokens for each user.

Shop (offline) tokens must still be maintained.

  1. Run the following generator to create a user model to store the individual based access tokens
rails generate shopify_app:user_model
  1. Configure config/initializers/shopify_app.rb to enable user access token persistance:
config.user_session_repository = 'User'

The current Shopify user will be stored in the rails session at session[:shopify_user]

You should also enable the check for session expiry so that a new access token can be fetched before being used for an API operation.

In-memory Session Storage for testing

The ShopifyApp gem includes methods for in-memory storage for both shop and user sessions. In-memory storage is intended to be used in a testing environment, please use a persistent storage for your application.

You can configure the ShopifyApp configuration to use the in-memory storage method during manual testing:

# config/initializers/shopify_app.rb

config.shop_session_repository = ShopifyApp::InMemoryShopSessionStore
config.user_session_repository = ShopifyApp::InMemoryUserSessionStore
Customizing Session Storage with ShopifyApp::SessionRepository

In the rare event that you would like to break Rails convention for storing/retrieving records, the ShopifyApp::SessionRepository allows you to define how your sessions are stored and retrieved for shops. The specific repository for shop & user is configured in the config/initializers/shopify_app.rb file and can be set to any object.

# config/initializers/shopify_app.rb

config.shop_session_repository = MyCustomShopSessionRepository
config.user_session_repository = MyCustomUserSessionRepository
⚠️ Custom Session Storage Requirements

The custom Shop repository must implement the following methods:

Method Parameters Return Type
self.store(auth_session) auth_session (ShopifyAPI::Auth::Session) -
self.retrieve(id) id (String) ShopifyAPI::Auth::Session
self.retrieve_by_shopify_domain(shopify_domain) shopify_domain (String) ShopifyAPI::Auth::Session
self.destroy_by_shopify_domain(shopify_domain) shopify_domain (String) -

The custom User repository must implement the following methods:

Method Parameters Return Type
self.store(auth_session, user)
  • auth_session (ShopifyAPI::Auth::Session)
  • user (ShopifyAPI::Auth::AssociatedUser)
    		•  -
    self.retrieve(id) id (String) ShopifyAPI::Auth::Session
    self.retrieve_by_shopify_user_id(user_id) user_id (String) ShopifyAPI::Auth::Session
    self.destroy_by_shopify_user_id(user_id) user_id (String) -

    These methods are already implemented as a part of the User and Shop models generated from this gem's generator.

    Available ActiveSupport::Concerns that contains implementation of the above methods

    Simply include these concerns if you want to use the implementation, and overwrite methods for custom implementation

    Loading Sessions

    By using the appropriate controller concern, sessions are loaded for you.

    Getting Sessions with Controller Concerns

    ⚠️ Note: These controller concerns cannot both be included in the same controller.

    Shop Sessions - EnsureInstalled
    • EnsureInstalled controller concern will load a shop session with the installed_shop_session helper. If a shop session is not found, meaning the app wasn't installed for this shop, the request will be redirected to be installed.
    • This controller concern should NOT be used if you don't need your app to make calls on behalf of a user.
    • Example
    class MyController < ApplicationController
  include ShopifyApp::EnsureInstalled

  def method
    current_session = installed_shop_session # `installed_shop_session` is a helper from `EnsureInstalled`

    client = ShopifyAPI::Clients::Graphql::Admin.new(session: current_session)
    client.query(
      # ...
    )
  end
end
    User Sessions - EnsureHasSession
    • EnsureHasSession controller concern will load a user session via current_shopify_session. As part of loading this session, this concern will also ensure that the user session has the appropriate scopes needed for the application and that it is not expired (when check_session_expiry_date is enabled). If the user isn't found or has fewer permitted scopes than are required, they will be prompted to authorize the application.
    • This controller concern should be used if you don't need your app to make calls on behalf of a user. With that in mind, there are a few other embedded concerns that are mixed in to ensure that embedding, CSRF, localization, and billing allow the action for the user.
    • Example
    class MyController < ApplicationController
  include ShopifyApp::EnsureHasSession

  def method
    current_session = current_shopify_session # `current_shopify_session` is a helper from `EnsureHasSession`

    client = ShopifyAPI::Clients::Graphql::Admin.new(session: current_session)
    client.query(
      # ...
    )
  end
end

    Getting sessions from a Shop or User model record - 'with_shopify_session'

    The ShopifyApp::SessionStorage#with_shopify_session helper allows you to make API calls within the context of a user or shop, by using that record's access token.

    This mixin is already included in ActiveSupport concerns from this gem. If you're using a custom implementation of session storage, you can include the ShopifyApp::SessionStorage concern.

    All calls made within the block passed into this helper will be made in that context:

    # To use shop context for "my_shopify_domain.myshopify.com"
shopify_domain = "my_shopify_domain.myshopify.com"
shop = Shop.find_by(shopify_domain: shopify_domain)
shop.with_shopify_session do
  ShopifyAPI::Product.find(id: product_id)
  # This will call the Shopify API with my_shopify_domain's access token
end

# To use user context for user ID "my_user_id"
user = User.find_by(shopify_user_id: "my_user_id")
user.with_shopify_session do
  ShopifyAPI::Product.find(id: product_id)
  # This will call the Shopify API with my_user_id's access token
end

    Re-fetching an access token when API returns Unauthorized

    When using ShopifyApp::EnsureHasSession and the new_embedded_auth_strategy configuration, any unhandled Unauthorized ShopifyAPI::Errors::HttpResponseError will cause the app to perform token exchange to fetch a new access token from Shopify and the action to be executed again. This will update and store the new access token to the current session instance.

    class MyController < ApplicationController
  include ShopifyApp::EnsureHasSession

  def index
    client = ShopifyAPI::Clients::Graphql::Admin.new(session: current_shopify_session)

    # If this call raises an Unauthorized error from Shopify, EnsureHasSession
    # will execute the action again after performing token exchange.
    # It will store and use the newly retrieved access token for this and any subsequent calls.
    client.query(options)
  end
end

    If the error is being rescued in the action, it's still possible to make use of with_token_refetch provided by EnsureHasSession so that a new access token is fetched and the code is executed again with it. This will also update the session parameter with the new attributes. This block should be used to wrap the code that makes API queries, so your business logic won't be retried.

    class MyController < ApplicationController
  include ShopifyApp::EnsureHasSession

  def index
    # Your app's business logic
    with_token_refetch(current_shopify_session, shopify_id_token) do
      # Unauthorized errors raised within this block will initiate token exchange.
      # `with_token_refetch` will store the new access token and use it
      # to execute this block again.
      # Any subsequent calls using the same session instance will have the new token.
      client = ShopifyAPI::Clients::Graphql::Admin.new(session: current_shopify_session)
      client.query(options)
    end
    # Your app's business logic continues
  rescue => error
    # app's specific error handling
  end
end

    It's also possible to use with_token_refetch on classes other than the controller by including the ShopifyApp::AdminAPI::WithTokenRefetch module and passing in the session along with the current request's shopify_id_token, which is provided by ShopifyApp::EnsureHasSession. This will also update the session parameter with the new attributes.

    # my_controller.rb
class MyController < ApplicationController
  include ShopifyApp::EnsureHasSession

  def index
    # shopify_id_token is a method provided by EnsureHasSession
    MyClass.new.do_things(current_shopify_session, shopify_id_token)
  end
end

# my_class.rb
class MyClass
  include ShopifyApp::AdminAPI::WithTokenRefetch

  def do_things(session, shopify_id_token)
    with_token_refetch(session, shopify_id_token) do
      # Unauthorized errors raised within this block will initiate token exchange.
      # `with_token_refetch` will store the new access token and use it
      # to execute this block again.
      # Any subsequent calls using the same session instance will have the new token.
      client = ShopifyAPI::Clients::Graphql::Admin.new(session: session)
      client.query(options)
    end
  rescue => error
    # app's specific error handling
  end
end

    If the retried block raises an Unauthorized error again, with_token_refetch will delete the current session from the database and raise the error again.

    class MyController < ApplicationController
  include ShopifyApp::EnsureHasSession

  def index
    client = ShopifyAPI::Clients::Graphql::Admin.new(session: current_shopify_session)
    with_token_refetch(current_shopify_session, shopify_id_token) do
      # When this call raises Unauthorized a second time during retry,
      # the `session` will be deleted from the database and the error raised
      client.query(options)
    end
  rescue => error
    # The Unauthorized error will reach this rescue
  end
end

    Access scopes

    If you want to customize how access scopes are stored for shops and users, you can implement the access_scopes getters and setters in the models that include ShopifyApp::ShopSessionStorageWithScopes and ShopifyApp::UserSessionStorageWithScopes as shown:

    ShopifyApp::ShopSessionStorageWithScopes

    class Shop < ActiveRecord::Base
  include ShopifyApp::ShopSessionStorageWithScopes

  def access_scopes=(scopes)
    # Store access scopes
  end
  def access_scopes
    # Find access scopes
  end
end

    ShopifyApp::UserSessionStorageWithScopes

    class User < ActiveRecord::Base
  include ShopifyApp::UserSessionStorageWithScopes

  def access_scopes=(scopes)
    # Store access scopes
  end
  def access_scopes
    # Find access scopes
  end
end

    Expiry date

    When the configuration flag check_session_expiry_date is set to true, the user session expiry date will be checked to trigger a re-auth and get a fresh user token when it is expired. This requires the ShopifyAPI::Auth::Session expires attribute to be stored. When the User model includes the UserSessionStorageWithScopes concern, a DB migration can be generated with rails generate shopify_app:user_model --skip to add the expires_at attribute to the model.

    Migrating from shop-based to user-based token strategy

    1. Run the user_model generator as mentioned above.
    • The generator will ask whether you want to migrate the User model to include access_scopes and expires_at columns. expires_at field is useful for detecting when the user session has expired and trigger a re-auth before an operation. It can reduce API failures for invalid access tokens. Configure the expiry date check to complete this feature.
    1. Ensure that both your Shop model and User model includes the necessary concerns
    2. Update the configuration file to use the new session storage.
    # config/initializers/shopify_app.rb

config.shop_session_repository = {YOUR_SHOP_MODEL_CLASS}
config.user_session_repository = {YOUR_USER_MODEL_CLASS}

    Migrating from ShopifyApi::Auth::SessionStorage to ShopifyApp::SessionStorage