Java tutorial
/* * Bosch SI Example Code License * Version 1.0, January 2016 * * Copyright 2017 Bosch Software Innovations GmbH ("Bosch SI"). All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the * following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following * disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the * following disclaimer in the documentation and/or other materials provided with the distribution. * * BOSCH SI PROVIDES THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO * THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF * ALL NECESSARY SERVICING, REPAIR OR CORRECTION. THIS SHALL NOT APPLY TO MATERIAL DEFECTS AND DEFECTS OF TITLE WHICH * BOSCH SI HAS FRAUDULENTLY CONCEALED. APART FROM THE CASES STIPULATED ABOVE, BOSCH SI SHALL BE LIABLE WITHOUT * LIMITATION FOR INTENT OR GROSS NEGLIGENCE, FOR INJURIES TO LIFE, BODY OR HEALTH AND ACCORDING TO THE PROVISIONS OF * THE GERMAN PRODUCT LIABILITY ACT (PRODUKTHAFTUNGSGESETZ). THE SCOPE OF A GUARANTEE GRANTED BY BOSCH SI SHALL REMAIN * UNAFFECTED BY LIMITATIONS OF LIABILITY. IN ALL OTHER CASES, LIABILITY OF BOSCH SI IS EXCLUDED. THESE LIMITATIONS OF * LIABILITY ALSO APPLY IN REGARD TO THE FAULT OF VICARIOUS AGENTS OF BOSCH SI AND THE PERSONAL LIABILITY OF BOSCH SI'S * EMPLOYEES, REPRESENTATIVES AND ORGANS. */ package com.bosch.iot.things.tutorial.ui; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.io.InputStream; import java.util.Base64; import java.util.Properties; import javax.servlet.ServletConfig; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.http.HttpHost; import org.apache.http.auth.AuthScope; import org.apache.http.auth.AuthenticationException; import org.apache.http.auth.UsernamePasswordCredentials; import org.apache.http.client.CredentialsProvider; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.impl.auth.BasicScheme; import org.apache.http.impl.client.BasicCredentialsProvider; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClientBuilder; import org.apache.http.message.BasicHttpRequest; /** * ProxyServlet to forward all requests to target service required as replacement for for cross domain requests. */ @WebServlet(ProxyServlet.URL_PATTERN) public class ProxyServlet extends HttpServlet { private static final String URL_PREFIX = "/api"; static final String URL_PATTERN = URL_PREFIX + "/*"; private HttpHost targetHost; private CloseableHttpClient httpClient; private Properties props; @Override public void init(ServletConfig config) throws ServletException { super.init(config); props = new Properties(System.getProperties()); if (new File("config.properties").exists()) { try (FileReader reader = new FileReader("config.properties")) { props.load(reader); } catch (IOException e) { throw new RuntimeException(e); } } else { try (InputStream is = Thread.currentThread().getContextClassLoader() .getResourceAsStream("config.properties")) { props.load(is); } catch (IOException e) { throw new RuntimeException(e); } } System.out.println("Config: " + props); targetHost = HttpHost.create( props.getProperty("thingsServiceEndpointUrl", "https://things.s-apps.de1.bosch-iot-cloud.com")); } @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { String auth = req.getHeader("Authorization"); if (auth == null) { resp.setHeader("WWW-Authenticate", "BASIC realm=\"Proxy for Bosch IoT Things\""); resp.sendError(HttpServletResponse.SC_UNAUTHORIZED); return; } try { long time = System.currentTimeMillis(); CloseableHttpClient c = getHttpClient(); String targetUrl = URL_PREFIX + req.getPathInfo() + (req.getQueryString() != null ? ("?" + req.getQueryString()) : ""); BasicHttpRequest targetReq = new BasicHttpRequest(req.getMethod(), targetUrl); String user = ""; if (auth.toUpperCase().startsWith("BASIC ")) { String userpassDecoded = new String(Base64.getDecoder().decode(auth.substring("BASIC ".length()))); user = userpassDecoded.substring(0, userpassDecoded.indexOf(':')); String pass = userpassDecoded.substring(userpassDecoded.indexOf(':') + 1); UsernamePasswordCredentials creds = new UsernamePasswordCredentials(user, pass); targetReq.addHeader(new BasicScheme().authenticate(creds, targetReq, null)); } targetReq.addHeader("x-cr-api-token", req.getHeader("x-cr-api-token")); CloseableHttpResponse targetResp = c.execute(targetHost, targetReq); System.out.println("Request: " + targetHost + targetUrl + ", user " + user + " -> " + (System.currentTimeMillis() - time) + " msec: " + targetResp.getStatusLine()); resp.setStatus(targetResp.getStatusLine().getStatusCode()); targetResp.getEntity().writeTo(resp.getOutputStream()); } catch (IOException | AuthenticationException ex) { throw new RuntimeException(ex); } } /** * Create http client */ private synchronized CloseableHttpClient getHttpClient() { if (httpClient == null) { HttpClientBuilder httpClientBuilder = HttpClientBuilder.create(); if (props.getProperty("proxyHost") != null) { httpClientBuilder.setProxy(new HttpHost(props.getProperty("proxyHost"), Integer.parseInt(props.getProperty("proxyPort")))); } if (props.getProperty("proxyUser") != null) { CredentialsProvider credsProvider = new BasicCredentialsProvider(); credsProvider.setCredentials(new AuthScope(targetHost), new UsernamePasswordCredentials( props.getProperty("proxyUser"), props.getProperty("proxyPwd"))); httpClientBuilder.setDefaultCredentialsProvider(credsProvider); } httpClient = httpClientBuilder.build(); } return httpClient; } }