Class: Karafka::Routing::TopicMapper

Inherits:
Object
  • Object
show all
Defined in:
lib/karafka/routing/topic_mapper.rb

Overview

Default topic mapper that does not remap things Mapper can be used for Kafka providers that require namespaced topic names. Instead of being provider dependent, we can then define mapper and use internally “pure” topic names in routes and responders

Examples:

Mapper for mapping prefixed topics

class MyMapper
  PREFIX = "my_user_name."

  def incoming(topic)
    topic.to_s.gsub(PREFIX, '')
  end

  def outgoing(topic)
    "#{PREFIX}#{topic}"
  end
end

Mapper for replacing “.” with “_” in topic names

class MyMapper
  PREFIX = "my_user_name."

  def incoming(topic)
    topic.to_s.gsub('.', '_')
  end

  def outgoing(topic)
    topic.to_s.gsub('_', '.')
  end
end

Instance Method Summary collapse

Instance Method Details

#incoming(topic) ⇒ String, Symbol

Returns same topic as on input.

Examples:

incoming('topic_name') #=> 'topic_name'

Parameters:

  • topic (String, Symbol) —

    topic

Returns:

  • (String, Symbol) —

    same topic as on input



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# File 'lib/karafka/routing/topic_mapper.rb', line 40

def incoming(topic)
  topic
end

#outgoing(topic) ⇒ String, Symbol

Returns same topic as on input.

Examples:

outgoing('topic_name') #=> 'topic_name'

Parameters:

  • topic (String, Symbol) —

    topic

Returns:

  • (String, Symbol) —

    same topic as on input



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# File 'lib/karafka/routing/topic_mapper.rb', line 48

def outgoing(topic)
  topic
end