Contents

# frozen_string_literal: true

require 'digest/md5'

module PgEventstore
  class Stream
    SYSTEM_STREAM_PREFIX = '$'
    NON_EXISTING_STREAM_REVISION = -1

    class << self
      # Produces "all" stream instance. "all" stream does not represent any specific stream. Instead, it indicates that
      # a specific command should be performed over any kind of streams if possible
      # @return [PgEventstore::Stream]
      def all_stream
        allocate.tap do |stream|
          stream.instance_variable_set(:@all_stream, true)
        end
      end
    end

    attr_reader :context, :stream_name, :stream_id

    # @param context [String]
    # @param stream_name [String]
    # @param stream_id [String]
    def initialize(context:, stream_name:, stream_id:)
      @context = context
      @stream_name = stream_name
      @stream_id = stream_id
    end

    # @return [Boolean]
    def all_stream?
      !!@all_stream
    end

    # Determine whether a stream is reserved by `pg_eventstore`. You can't append events to such streams.
    # @return [Boolean]
    def system?
      all_stream? || context.start_with?(SYSTEM_STREAM_PREFIX)
    end

    # @return [Array]
    def deconstruct
      [context, stream_name, stream_id]
    end
    alias to_a deconstruct

    # @param keys [Array<Symbol>, nil]
    def deconstruct_keys(keys)
      hash = { context: context, stream_name: stream_name, stream_id: stream_id }
      return hash unless keys

      hash.slice(*keys)
    end

    # @return [Hash]
    def to_hash
      deconstruct_keys(nil)
    end

    # @return [Integer]
    def hash
      to_hash.hash
    end

    # @param another [Object]
    # @return [Boolean]
    def eql?(another)
      return false unless another.is_a?(Stream)

      hash == another.hash
    end

    def ==(other_stream)
      return false unless other_stream.is_a?(Stream)

      to_hash == other_stream.to_hash
    end
  end
end

Version data entries

5 entries across 5 versions & 1 rubygems

Version	Path
pg_eventstore-1.0.4	lib/pg_eventstore/stream.rb
pg_eventstore-1.0.0.rc2	lib/pg_eventstore/stream.rb
pg_eventstore-1.0.0.rc1	lib/pg_eventstore/stream.rb
pg_eventstore-0.10.2	lib/pg_eventstore/stream.rb
pg_eventstore-0.10.1	lib/pg_eventstore/stream.rb