Class: Karafka::Pro::Routing::Features::Patterns::Pattern

Inherits:
Object
  • Object
show all
Defined in:
lib/karafka/pro/routing/features/patterns/pattern.rb

Overview

Karafka topic pattern object It represents a topic that is not yet materialized and that contains a name that is a regexp and not a “real” value. Underneath we define a dynamic topic, that is not active, that can be a subject to normal flow validations, etc.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, regexp, config) ⇒ Pattern 



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 42

def initialize(name, regexp, config)
  @regexp = regexp
  # This name is also used as the underlying matcher topic name
  #
  # It can be used provided by the user in case user wants to use exclusions of topics
  # or we can generate it if irrelevant.
  #
  # We generate it based on the regexp so within the same consumer group they are
  # always unique (checked by topic validations)
  #
  # This will not prevent users from creating a different regexps matching the same
  # topic but this minimizes simple mistakes
  #
  # This sub-part of sh1 should be unique enough and short-enough to use it here
  digest = Digest::SHA1.hexdigest(safe_regexp.source)[8..16]
  @name = name ? name.to_s : "karafka-pattern-#{digest}"
  @config = config
end

Instance Attribute Details

#config ⇒ Object (readonly)

Config for real-topic configuration during injection



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 36

def config
  @config
end

#name ⇒ Object (readonly)

Each pattern has its own “topic” that we use as a routing reference that we define with non-existing topic for the routing to correctly pick it up for operations Virtual topic name for initial subscription



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 30

def name
  @name
end

#regexp ⇒ Object

Pattern regexp



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 25

def regexp
  @regexp
end

#topic ⇒ Object

Associated created virtual topic reference



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 33

def topic
  @topic
end

Instance Method Details

#regexp_string ⇒ String 



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 64

def regexp_string
  "^#{safe_regexp.source}"
end

#to_h ⇒ Hash 



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# File 'lib/karafka/pro/routing/features/patterns/pattern.rb', line 69

def to_h
  {
    regexp: regexp,
    name: name,
    regexp_string: regexp_string
  }.freeze
end