| # Licensed to the Apache Software Foundation (ASF) under one or more |
| # contributor license agreements. See the NOTICE file distributed with |
| # this work for additional information regarding copyright ownership. |
| # The ASF licenses this file to You under the Apache License, Version 2.0 |
| # (the "License"); you may not use this file except in compliance with |
| # the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| module PredictionIO |
| |
| # This class handles multithreading and asynchronous requests transparently for the REST client. |
| class Connection |
| |
| # Number of pending asynchronous request and response packages. |
| attr_reader :packages |
| |
| # Number of connections active |
| attr_reader :connections |
| |
| # Timeout in seconds |
| attr_reader :timeout |
| |
| # Spawns a number of threads with persistent HTTP connection to the specified URI. |
| # Sets a default timeout of 60 seconds. |
| def initialize(uri, threads = 1, timeout = 60) |
| @packages = Queue.new |
| @counter_lock = Mutex.new |
| @connections = 0 |
| @timeout = timeout |
| threads.times do |
| Thread.new do |
| begin |
| Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == 'https') do |http| |
| @counter_lock.synchronize do |
| @connections += 1 |
| end |
| catch(:exit) do |
| http.read_timeout = @timeout |
| loop do |
| package = @packages.pop |
| request = package[:request] |
| response = package[:response] |
| case package[:method] |
| when 'get' |
| http_req = Net::HTTP::Get.new("#{uri.path}#{request.qpath}") |
| begin |
| response.set(http.request(http_req)) |
| rescue Exception => details |
| response.set(details) |
| end |
| when 'post' |
| if request.params.is_a?(Hash) |
| http_req = Net::HTTP::Post.new("#{uri.path}#{request.path}") |
| http_req.set_form_data(request.params) |
| else |
| http_req = Net::HTTP::Post.new("#{uri.path}#{request.path}", initheader = { 'Content-Type' => 'application/json; charset=utf-8' }) |
| http_req.body = request.params |
| end |
| begin |
| response.set(http.request(http_req)) |
| rescue Exception => details |
| response.set(details) |
| end |
| when 'delete' |
| http_req = Net::HTTP::Delete.new("#{uri.path}#{request.qpath}") |
| begin |
| response.set(http.request(http_req)) |
| rescue Exception => details |
| response.set(details) |
| end |
| when 'exit' |
| @counter_lock.synchronize do |
| @connections -= 1 |
| end |
| throw :exit |
| end |
| end |
| end |
| end |
| rescue Exception => detail |
| @counter_lock.synchronize do |
| if @connections == 0 then |
| # Use non-blocking pop to avoid dead-locking the current |
| # thread when there is no request, and give it a chance to re-connect. |
| begin |
| package = @packages.pop(true) |
| response = package[:response] |
| response.set(detail) |
| rescue Exception |
| end |
| end |
| end |
| sleep(1) |
| retry |
| end |
| end |
| end |
| end |
| |
| # Create an asynchronous request and response package, put it in the pending queue, and return the response object. |
| def request(method, request) |
| response = AsyncResponse.new(request) |
| @packages.push(method: method, request: request, response: response) |
| response |
| end |
| |
| # Shortcut to create an asynchronous GET request with the response object returned. |
| def aget(areq) |
| request('get', areq) |
| end |
| |
| # Shortcut to create an asynchronous POST request with the response object returned. |
| def apost(areq) |
| request('post', areq) |
| end |
| |
| # Shortcut to create an asynchronous DELETE request with the response object returned. |
| def adelete(areq) |
| request('delete', areq) |
| end |
| end |
| end |