Class: Philiprehberger::Middleware::FrozenStack

Inherits:
Object
  • Object
show all
Defined in:
lib/philiprehberger/middleware/stack.rb

Overview

An immutable snapshot of a middleware stack that can execute but not be modified.

Instance Method Summary collapse

Constructor Details

#initialize(entries, groups, disabled_groups, before_hooks, after_hooks, around_hooks) ⇒ FrozenStack

Returns a new instance of FrozenStack.



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# File 'lib/philiprehberger/middleware/stack.rb', line 525

def initialize(entries, groups, disabled_groups, before_hooks, after_hooks, around_hooks)
  @entries = entries.freeze
  @groups = groups.freeze
  @disabled_groups = disabled_groups.freeze
  @before_hooks = before_hooks.freeze
  @after_hooks = after_hooks.freeze
  @around_hooks = around_hooks.freeze
end

Instance Method Details

#[](target_name) ⇒ #call?

Look up an entry by name.

Parameters:

  • target_name (String, Symbol) —

    name of the entry

Returns:

  • (#call, nil) —

    the middleware callable, or nil if not found



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# File 'lib/philiprehberger/middleware/stack.rb', line 564

def [](target_name)
  entry = @entries.find { |e| e.name == target_name }
  entry&.middleware
end

#call(env) ⇒ Object

Execute the frozen middleware stack with the given environment.

Parameters:

  • env (Object) —

    the environment/context passed through the stack

Returns:

  • (Object) —

    the final environment after all middleware have run



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# File 'lib/philiprehberger/middleware/stack.rb', line 538

def call(env)
  disabled = disabled_middleware_names
  terminal = ->(e) { e }
  chain = @entries.reverse.reduce(terminal) do |next_mw, entry|
    if entry.name && disabled.include?(entry.name)
      next_mw
    else
      build_frozen_step(entry, next_mw)
    end
  end
  chain.call(env)
rescue Philiprehberger::Middleware::Halt
  env
end

#to_a ⇒ Array<String, Symbol, nil>

Return the list of middleware names.

Returns:

  • (Array<String, Symbol, nil>) —

    names of middleware in order



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# File 'lib/philiprehberger/middleware/stack.rb', line 556

def to_a
  @entries.map(&:name)
end