caching_handler.cr

class CachingHandler < Kemal::Handler

	property cache : Hash(String, Bytes)

	def initialize
		@cache = Hash(String, Bytes).new
	end

	def call(context)
		puts "Caching"
		puts "Key: #{ context.request.resource }"
		if output = @cache[context.request.resource]?
			puts "Cache: true"
			# IO.copy output, context.response.output
			context.response.write output
		else
			puts "Cache: false"
			puts "Cache: building"
			memBuffer = IO::Memory.new
			context.response.output = IO::MultiWriter.new context.response.output, memBuffer

			# continue
			puts "Cache: continue"
			ret = call_next context

			puts "Cache: Response: #{ context.response.inspect }"
			puts "Cache: memBuffer: #{ memBuffer.inspect }"

			buffer = memBuffer.to_slice
			# return
			context.response.write(@cache[context.request.resource] = buffer)
			context.response.flush
			context.response.close
			context.response.output.flush
			context.response.output.close
			ret
		end
	end
end