Module: Funes

Defined in:
lib/funes.rb,
lib/funes/engine.rb,
lib/funes/version.rb,
lib/funes/inspection.rb,
app/models/funes/event.rb,
lib/funes/associations.rb,
lib/funes/configuration.rb,
lib/funes/unknown_event.rb,
app/models/funes/event_entry.rb,
app/jobs/funes/application_job.rb,
app/projections/funes/projection.rb,
app/models/funes/application_record.rb,
app/event_streams/funes/event_stream.rb,
app/helpers/funes/application_helper.rb,
app/mailers/funes/application_mailer.rb,
app/jobs/funes/persist_projection_job.rb,
lib/generators/funes/install_generator.rb,
lib/funes/conflicting_actual_time_error.rb,
lib/funes/event_metainformation_builder.rb,
lib/funes/invalid_event_metainformation.rb,
lib/funes/invalid_materialization_state.rb,
lib/funes/unknown_materialization_model.rb,
app/helpers/funes/projection_test_helper.rb,
lib/generators/funes/initializer_generator.rb,
app/controllers/funes/application_controller.rb,
app/serializers/funes/event_stream_serializer.rb,
lib/funes/missing_actual_time_attribute_error.rb,
lib/generators/funes/materialization_table_generator.rb

Overview

Funes is an event sourcing framework for Ruby on Rails.

Instead of updating state in place, Funes stores immutable events as the source of truth, then derives current state by replaying them through projections. This provides complete audit trails, temporal queries, and the ability to create multiple read models from the same event stream.

Core Concepts

  • Events (Event): Immutable facts representing something that happened
  • Event Streams (EventStream): Append-only sequences of events for a specific entity
  • Projections (Projection): Transform events into read models (state)

Getting Started

  1. Install the gem and run migrations:

    $ bin/rails generate funes:install
$ bin/rails db:migrate

  2. Define your events:

    class Order::Placed < Funes::Event
  attribute :total, :decimal
  attribute :customer_id, :string
  validates :total, presence: true
end

  3. Define a projection:

    class OrderProjection < Funes::Projection
  materialization_model OrderSnapshot

  interpretation_for Order::Placed do |state, event, _at|
    state.assign_attributes(total: event.total)
    state
  end
end

  4. Create an event stream:

    class OrderEventStream < Funes::EventStream
  add_transactional_projection OrderProjection
end

  5. Append events:

    stream = OrderEventStream.for("order-123")
event = stream.append(Order::Placed.new(total: 99.99, customer_id: "cust-1"))

Three-Tier Consistency Model

Funes provides fine-grained control over projection execution:

  • Consistency Projection: Validates business rules before persisting events
  • Transactional Projections: Execute synchronously in the same database transaction
  • Async Projections: Execute asynchronously via ActiveJob

Bitemporal History

Funes supports two independent temporal dimensions:

  • Record history (as_of / created_at): When the system learned about an event
  • Actual history (at / occurred_at): When the event actually occurred in the real world

This enables queries like "what did the system know at time T?" (as_of) and "what had actually happened by time T?" (at), as well as full bitemporal queries combining both dimensions.

See Also:

Defined Under Namespace

Modules: ApplicationHelper, Associations, Generators, Inspection, ProjectionTestHelper Classes: ApplicationController, ApplicationJob, ApplicationMailer, ApplicationRecord, Configuration, ConflictingActualTimeError, Engine, Event, EventEntry, EventMetainformation, EventMetainformationBuilder, EventStream, EventStreamSerializer, InvalidEventMetainformation, InvalidMaterializationState, MissingActualTimeAttributeError, PersistProjectionJob, Projection, UnknownEvent, UnknownMaterializationModel

Constant Summary collapse

VERSION = 
"0.3.0"

Class Method Summary collapse

Class Method Details

.configuration ⇒ Object 



92
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94
 
# File 'lib/funes.rb', line 92

def configuration
  @configuration ||= Configuration.new
end

.configure {|configuration| ... } ⇒ Object

Yields:



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# File 'lib/funes.rb', line 96

def configure
  yield(configuration)
end