Stream Rails

stream-rails is a Ruby on Rails client for Stream.

You can sign up for a Stream account at https://getstream.io/get_started.

Note there is also a lower level Ruby - Stream integration library which is suitable for all Ruby applications.

💡 This is a library for the Feeds product. The Chat SDKs can be found here.

What you can build:

• Activity streams such as seen on Github
• A twitter style newsfeed
• A feed like instagram/ pinterest
• Facebook style newsfeeds
• A notification system

You can check out our example app built using this library on Github https://github.com/GetStream/Stream-Example-Rails

• Activity Streams & Newsfeeds
• Demo
• Table of Contents
• Gem installation
• Setup
• Supported ORMs
  • ActiveRecord
  • Sequel
• Model configuration
  • Activity fields
  • Activity extra data
  • Activity creation
• Feed manager
  • Feeds bundled with feed_manager
    • User feed:
    • News feeds:
    • Notification feed:
  • Follow a feed
• Showing the newsfeed
  • Activity enrichment
  • Templating
  • Pagination
• Disable model tracking
• Running specs
• Full documentation and Low level APIs access
• Copyright and License Information

You can install stream_rails as you would any other gem:

gem install stream_rails

or in your Gemfile:

gem 'stream_rails'

This library is tested against and fully supports the following Rails versions:

• 5.0
• 5.2
• 6.0
• 6.1

Login with Github on getstream.io and get your api_key and api_secret from your app configuration (Dashboard screen).

Then you can add the StreamRails configuration in config/initializers/stream_rails.rb

require 'stream_rails'

StreamRails.configure do |config|
  config.api_key      = "YOUR API KEY"
  config.api_secret   = "YOUR API SECRET"
  config.timeout      = 30                  # Optional, defaults to 3
  config.location     = 'us-east'           # Optional, defaults to 'us-east'
  config.api_hostname = 'stream-io-api.com' # Optional, defaults to 'stream-io-api.com'
  # If you use custom feed names, e.g.: timeline_flat, timeline_aggregated,
  # use this, otherwise omit:
  config.news_feeds = { flat: "timeline_flat", aggregated: "timeline_aggregated" }
  # Point to the notifications feed group providing the name, omit if you don't
  # have a notifications feed
  config.notification_feed = "notification"
end

The integration will look as follows:

class Pin < ActiveRecord::Base
  include StreamRails::Activity
  as_activity

  def activity_object
    self.item
  end
end

Please, use Sequel ~5.

The integration will look as follows:

class Pin < Sequel::Model
  include StreamRails::Activity
  as_activity

  def activity_object
    self.item
  end
end

Include StreamRails::Activity and add as_activity to the model you want to integrate with your feeds.

class Pin < ActiveRecord::Base
  belongs_to :user
  belongs_to :item

  validates :item, presence: true
  validates :user, presence: true

  include StreamRails::Activity
  as_activity

  def activity_object
    self.item
  end

end

Everytime a Pin is created it will be stored in the feed of the user that created it. When a Pin instance is deleted, the feed will be removed as well.

ActiveRecord models are stored in your feeds as activities; Activities are objects that tell the story of a person performing an action on or with an object, in its simplest form, an activity consists of an actor, a verb, and an object. In order for this to happen your models need to implement these methods:

#activity_object the object of the activity (eg. an AR model instance)

#activity_actor the actor performing the activity -- this value also provides the feed name and feed ID to which the activity will be added.

For example, let's say a Pin was a polymorphic class that could belong to either a user (e.g. User ID: 1) or a company (e.g. Company ID: 1). In that instance, the below code would post the pin either to the user:1 feed or the company:1 feed based on its owner.

class Pin < ActiveRecord::Base
  belongs_to :owner, :polymorphic => true
  belongs_to :item

  include StreamRails::Activity
  as_activity

  def activity_actor
    self.owner
  end

  def activity_object
    self.item
  end

end

The activity_actor defaults to self.user

#activity_verb the string representation of the verb (defaults to model class name)

Here's a more complete example of the Pin class:

class Pin < ActiveRecord::Base
  belongs_to :author
  belongs_to :item

  include StreamRails::Activity
  as_activity

  def activity_actor
    self.author
  end

  def activity_object
    self.item
  end

end

Often you'll want to store more data than just the basic fields. You achieve this by implementing #activity_extra_data in your model.

class Pin < ActiveRecord::Base
  belongs_to :author
  belongs_to :item

  include StreamRails::Activity
  as_activity

  def activity_extra_data
    {'is_retweet' => self.is_retweet}
  end

  def activity_object
    self.item
  end

end

If you want to control when to create an activity you should implement the #activity_should_sync? method in your model.

class Pin < ActiveRecord::Base
  belongs_to :author
  belongs_to :item

  include StreamRails::Activity
  as_activity

  def activity_should_sync?
    self.published
  end

  def activity_object
    self.item
  end

end

This will create an activity only when self.published is true.

stream_rails comes with a Feed Manager class that helps with all common feed operations. You can get an instance of the manager with StreamRails.feed_manager.

feed = StreamRails.feed_manager.get_user_feed(current_user.id)

To get you started the manager has 4 feeds pre-configured. You can add more feeds if your application requires it. Feeds are divided into three categories.

The user feed stores all activities for a user. Think of it as your personal Facebook page. You can easily get this feed from the manager.

feed = StreamRails.feed_manager.get_user_feed(current_user.id)

News feeds store activities from the people you follow. There is both a flat newsfeed (similar to twitter) and an aggregated newsfeed (like facebook).

feed = StreamRails.feed_manager.get_news_feeds(current_user.id)[:flat]
aggregated_feed = StreamRails.feed_manager.get_news_feeds(current_user.id)[:aggregated]

The notification feed can be used to build notification functionality.

Below we show an example of how you can read the notification feed.

notification_feed = StreamRails.feed_manager.get_notification_feed(current_user.id)

By default the notification feed will be empty. You can specify which users to notify when your model gets created. In the case of a retweet you probably want to notify the user of the parent tweet.

class Pin < ActiveRecord::Base
  belongs_to :author
  belongs_to :item

  include StreamRails::Activity
  as_activity

  def activity_notify
    if self.is_retweet
      [StreamRails.feed_manager.get_notification_feed(self.parent.user_id)]
    end
  end

  def activity_object
    self.item
  end

end

Another example would be following a user. You would commonly want to notify the user which is being followed.

class Follow < ActiveRecord::Base
  belongs_to :user
  belongs_to :target

  validates :target_id, presence: true
  validates :user, presence: true

  include StreamRails::Activity
  as_activity

  def activity_notify
    [StreamRails.feed_manager.get_notification_feed(self.target_id)]
  end

  def activity_object
    self.target
  end

end

In order to populate newsfeeds, you need to notify the system about follow relationships.

The current user's flat and aggregated feeds will follow the target_user's user feed, with the following code:

StreamRails.feed_manager.follow_user(user_id, target_id)

When you read data from feeds, a pin activity will look like this:

{ "actor": "User:1", "verb": "like", "object": "Item:42" }

This is far from ready for usage in your template. We call the process of loading the references from the database "enrichment." An example is shown below:

enricher = StreamRails::Enrich.new

feed = StreamRails.feed_manager.get_news_feeds(current_user.id)[:flat]
results = feed.get()['results']
activities = enricher.enrich_activities(results)

A similar method called enrich_aggregated_activities is available for aggregated feeds.

enricher = StreamRails::Enrich.new

feed = StreamRails.feed_manager.get_news_feeds(current_user.id)[:aggregated]
results = feed.get()['results']
activities = enricher.enrich_aggregated_activities(results)

If you have additional metadata in your activity (by overriding activity_extra_data in the class where you add the Stream Activity mixin), you can also enrich that field's data by doing the following:

Step One: override the activity_extra_data method from our mixin:

class Pin < ActiveRecord::Base
  include StreamRails::Activity
  as_activity

  attr_accessor :extra_data

  def activity_object
    self.item
  end

  # override this method to add metadata to your activity
  def activity_extra_data
    @extra_data
  end
end

Now we'll create a 'pin' object which has a location metadata field. In this example, we will also have a location table and model, and we set up our metadata in the extra_data field. It is important that the symbol of the metadata as well as the value of the meta data match this pattern. The left half of the string:string metadata value when split on : must also match the name of the model.

We must also tell the enricher to also fetch locations when looking through our activities

boulder = Location.new
boulder.name = "Boulder, CO"
boulder.save!

# tell the enricher to also do a lookup on the `location` model
enricher.add_fields([:location])

pin = Pin.new
pin.user = @tom
pin.extra_data = {:location => "location:#{boulder.id}"}

When we retrieve the activity later, the enrichment process will include our location model as well, giving us access to attributes and methods of the location model:

place = activity[:location].name
# Boulder, CO

Now that you've enriched the activities you can render them in a view. For convenience we include a basic view:

<div class="container">
    <div class="container-pins">
        <% for activity in @activities %>
            <%= render_activity activity %>
        <% end %>
    </div>
</div>

The render_activity view helper will render the activity by picking the partial activity/_pin for a pin activity, aggregated_activity/_follow for an aggregated activity with verb follow.

The helper will automatically send activity to the local scope of the partial; additional parameters can be sent as well as use different layouts, and prefix the name

e.g. renders the activity partial using the small_activity layout:

<%= render_activity activity, :layout => "small_activity" %>

e.g. prefixes the name of the template with "notification_":

<%= render_activity activity, :prefix => "notification_" %>

e.g. adds the extra_var to the partial scope:

<%= render_activity activity, :locals => {:extra_var => 42} %>

e.g. renders the activity partial using the notifications partial root, which will render the partial with the path notifications/#{ACTIVITY_VERB}

<%= render_activity activity, :partial_root => "notifications" %>

For simple pagination you can use the stream-ruby API, as follows in your controller:

  StreamRails.feed_manager.get_news_feeds(current_user.id)[:flat] # Returns a Stream::Feed object
  results = feed.get(limit: 5, offset: 5)['results']

You can disable model tracking (eg. when you run tests) via StreamRails.configure

require 'stream_rails'

StreamRails.enabled = false

From the project root directory:

./bin/run_tests.sh

When needed you can also use the low level Ruby API directly. Documentation is available at the Stream website.

Copyright (c) 2014-2021 Stream.io Inc, and individual contributors. All rights reserved.

See the file "LICENSE" for information on the history of this software, terms & conditions for usage, and a DISCLAIMER OF ALL WARRANTIES.