Class: Maxwell::Agent::Middleware::Chain

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/maxwell/agent/middleware/chain.rb

Defined Under Namespace

Classes: Entry

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize {|_self| ... } ⇒ Chain

Returns a new instance of Chain.

Yields:

  • (_self)

Yield Parameters:



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# File 'lib/maxwell/agent/middleware/chain.rb', line 8

def initialize
  @entries = []
  yield self if block_given?
end

Instance Attribute Details

#entries ⇒ Object (readonly)

Returns the value of attribute entries.



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# File 'lib/maxwell/agent/middleware/chain.rb', line 6

def entries
  @entries
end

Instance Method Details

#add(klass, *args) ⇒ Object 



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# File 'lib/maxwell/agent/middleware/chain.rb', line 17

def add(klass, *args)
  new_entry = Entry.new(klass, *args)
  if count > 0
    add_at(count + 1, new_entry)
  else
    add_at(count, new_entry)
  end
end

#each(&block) ⇒ Object 



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# File 'lib/maxwell/agent/middleware/chain.rb', line 13

def each(&block)
  entries.each(&block)
end

#insert_after(existing_klass, new_klass, *args) ⇒ Object 



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# File 'lib/maxwell/agent/middleware/chain.rb', line 36

def insert_after(existing_klass, new_klass, *args)
  new_entry = Entry.new(new_klass, *args)
  i = get_index(existing_klass) || count - 1
  add_at(i + 1, new_entry)
end

#insert_before(existing_klass, new_klass, *args) ⇒ Object 



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# File 'lib/maxwell/agent/middleware/chain.rb', line 30

def insert_before(existing_klass, new_klass, *args)
  new_entry = Entry.new(new_klass, *args)
  i = get_index(existing_klass) || 0
  add_at(i, new_entry)
end

#invoke(*args, &final_action) ⇒ Object 



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# File 'lib/maxwell/agent/middleware/chain.rb', line 42

def invoke(*args, &final_action)
  chain = retrieve.dup

  traverse_chain = -> do
    if chain.empty?
      final_action.call if final_action
    else
      chain.shift.call(*args, &traverse_chain)
    end
  end
  traverse_chain.call
end

#remove(entry) ⇒ Object 



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# File 'lib/maxwell/agent/middleware/chain.rb', line 26

def remove(entry)
  entries.delete_if {|e| e }
end