Module: Datadog::AIGuard::Contrib::Rails::Patcher

Defined in:
lib/datadog/ai_guard/contrib/rails/patcher.rb

Overview

Patcher for AI Guard on Rails. Inserts the AI Guard Rack middleware right after the Tracing Rack middleware so the request span is already active when AI Guard tags the client IP.

Constant Summary collapse

BEFORE_INITIALIZE_ONLY_ONCE_PER_APP = 
Hash.new { |h, key| h[key] = Datadog::Core::Utils::OnlyOnce.new }

Class Method Summary collapse

Class Method Details

.add_middleware(app) ⇒ Object 



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 47

def add_middleware(app)
  if include_middleware?(Datadog::Tracing::Contrib::Rack::TraceMiddleware, app)
    app.middleware.insert_after(
      Datadog::Tracing::Contrib::Rack::TraceMiddleware,
      Datadog::AIGuard::Contrib::Rack::RequestMiddleware
    )
  else
    app.middleware.insert_before(0, Datadog::AIGuard::Contrib::Rack::RequestMiddleware)
  end
end

.before_initialize(app) ⇒ Object 



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 39

def before_initialize(app)
  BEFORE_INITIALIZE_ONLY_ONCE_PER_APP[app].run do
    # Middleware must be added before the application is initialized.
    # Otherwise the middleware stack will be frozen.
    add_middleware(app) if Datadog.configuration.tracing[:rails][:middleware]
  end
end

.include_middleware?(middleware, app) ⇒ Boolean

Returns:



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 58

def include_middleware?(middleware, app)
  found = false

  # find tracer middleware reference in Rails::Configuration::MiddlewareStackProxy
  app.middleware.instance_variable_get(:@operations).each do |operation|
    args = case operation
    when Array
      # rails 5.2
      _op, args = operation
      args
    when Proc
      if operation.binding.local_variables.include?(:args)
        # rails 6.0, 6.1
        operation.binding.local_variable_get(:args)
      else
        # rails 7.0 uses ... to pass args
        # steep:ignore:start
        args_getter = Class.new do
          def method_missing(_op, *args) # standard:disable Style/MissingRespondToMissing
            args
          end
        end.new
        # steep:ignore:end
        operation.call(args_getter)
      end
    else
      # unknown, pass through
      []
    end

    found = true if args.include?(middleware)
  end

  found
end

.patch ⇒ Object 



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 28

def patch
  patch_before_initialize
  Patcher.instance_variable_set(:@patched, true)
end

.patch_before_initialize ⇒ Object 



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 33

def patch_before_initialize
  ::ActiveSupport.on_load(:before_initialize) do
    Datadog::AIGuard::Contrib::Rails::Patcher.before_initialize(self)
  end
end

.patched? ⇒ Boolean

Returns:



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 20

def patched?
  !!Patcher.instance_variable_get(:@patched)
end

.target_version ⇒ Object 



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# File 'lib/datadog/ai_guard/contrib/rails/patcher.rb', line 24

def target_version
  Integration.version
end