war/src/main/java/pnews/servlet/Pnews.java

   1 package pnews.servlet;
   2
   3 import java.io.IOException;
   4 import java.io.InputStream;
   5 import java.io.InputStreamReader;
   6 import java.io.Reader;
   7 import java.io.UnsupportedEncodingException;
   8 import java.io.Writer;
   9 import java.net.URLDecoder;
  10 import java.util.ArrayList;
  11 import java.util.List;
  12 import java.util.logging.Level;
  13 import java.util.logging.Logger;
  14
  15 import javax.servlet.ServletConfig;
  16 import javax.servlet.ServletException;
  17 import javax.servlet.http.HttpServlet;
  18 import javax.servlet.http.HttpServletRequest;
  19 import javax.servlet.http.HttpServletResponse;
  20
  21 import com.rometools.rome.io.FeedException;
  22
  23 import pnews.Article;
  24 import pnews.Category;
  25 import pnews.Language;
  26
  27 public class Pnews extends HttpServlet {
  28         private static final String CLASS_NAME = Pnews.class.getName();
  29         private static final Logger LOG = Logger.getLogger(Pnews.class.getName());
  30         private static final long serialVersionUID = 1L;
  31         private ArticleProvider provider;
  32         private Config config;
  33
  34         private static String getQueryParameter(HttpServletRequest rq, String key)
  35                         throws UnsupportedEncodingException {
  36                 final String METHOD_NAME="getQueryParameter";
  37                 String[] params;
  38                 int idx;
  39                 String q;
  40
  41
  42                 LOG.entering(CLASS_NAME, METHOD_NAME, new Object[] { rq, key} );
  43
  44                 q = rq.getQueryString();
  45
  46                 if (q == null)
  47                         return null;
  48
  49                 params = q.split("&");
  50
  51                 for (String p: params) {
  52                         idx = p.indexOf('=');
  53
  54                         if (idx > 1 && p.substring(0, idx).equals(key))
  55                                 return URLDecoder.decode(p.substring(idx + 1), "UTF-8");
  56                 }
  57
  58                 return null;
  59         }
  60
  61         private static void redirect(HttpServletRequest rq, HttpServletResponse rp) {
  62                 String redirectURL;
  63                 Article a;
  64
  65                 LOG.entering(Pnews.class.getName(), "redirect", new Object[] { rq, rp });
  66
  67                 try {
  68                         redirectURL = getQueryParameter(rq, "url");
  69
  70                         LOG.info("Request redirection to " + redirectURL);
  71
  72                         if (redirectURL != null) {
  73                                 a = ArticleStore.singleton.get(redirectURL);
  74                                 if (a != null)
  75                                         a.readCount.incrementAndGet();
  76                                 else
  77                                         LOG.severe("Cannot find the article " + redirectURL);
  78
  79                                 rp.setHeader("Location", redirectURL);
  80                                 rp.setStatus(HttpServletResponse.SC_TEMPORARY_REDIRECT);
  81                         } else {
  82                                 LOG.severe("No redirection URL");
  83                                 rp.setStatus(HttpServletResponse.SC_NOT_FOUND);
  84                         }
  85
  86                 } catch (UnsupportedEncodingException e) {
  87                         e.printStackTrace();
  88                         LOG.log(Level.SEVERE, "redirect failure", e);
  89                         rp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
  90                 }
  91
  92                 LOG.exiting(Pnews.class.getName(), "redirect");
  93         }
  94
  95         private static void doTemporaryRedirect(String newURL, HttpServletResponse rp) {
  96                 rp.setHeader("Location", newURL);
  97                 rp.setStatus(HttpServletResponse.SC_TEMPORARY_REDIRECT);
  98         }
  99
 100         private void writeStats(HttpServletResponse rp) throws IOException {
 101                 rp.setContentType("application/json;charset=utf-8");
 102                 rp.setCharacterEncoding("utf-8");
 103
 104                 rp.getWriter().write(JSON.getStats(provider, config));
 105         }
 106
 107
 108         private void writeArticles(Category cat, String entity, HttpServletResponse rp) {
 109                 String html;
 110                 List<Article> articles;
 111
 112                 try {
 113                         articles = provider.getArticles(cat, entity);
 114                         if (articles != null) {
 115                                 html = HTML.toHTML(articles, cat, entity, config, provider);
 116                                 rp.setContentType("text/html;charset=utf-8");
 117                                 rp.getWriter().write(html);
 118                                 rp.setCharacterEncoding("utf-8");
 119                         } else {
 120                                 LOG.severe("writeArticles cannot retrieve any articles");
 121                                 html = HTML.toHTML(new ArrayList<Article>(), cat, entity, config, provider);
 122                                 rp.setContentType("text/html");
 123                                 rp.getWriter().write(html);
 124                         }
 125                 } catch (IOException | IllegalArgumentException | FeedException e) {
 126                         LOG.log(Level.SEVERE, "writeArticles failure", e);
 127                         rp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
 128                 }
 129         }
 130
 131         private void copy(InputStream in, Writer writer) throws IOException {
 132                 Reader r;
 133                 char[] buf;
 134                 int n;
 135
 136                 buf = new char[1024];
 137                 r = new InputStreamReader(in);
 138                 while ( (n = r.read(buf, 0, buf.length)) != -1)
 139                         writer.write(buf, 0, n);
 140         }
 141
 142         @Override
 143         protected void doGet(HttpServletRequest req, HttpServletResponse resp) {
 144                 final String METHOD_NAME = "doGet";
 145                 String path;
 146                 InputStream in;
 147
 148                 RequesterLog.singleton.writeRequest(req);
 149
 150                 LOG.info("doGet " + req.getRemoteAddr().toString() + " " + req.getRequestURI() + " " + req.getQueryString());
 151
 152                 LOG.info(METHOD_NAME + " queryString=" + req.getQueryString());
 153
 154                 path = req.getPathInfo();
 155
 156                 if (path.equals("/redirect")) {
 157                         redirect(req, resp);
 158                         return ;
 159                 }
 160
 161                 if (path.equals("/style.css")) {
 162                         try {
 163                                 in = HTML.class.getClassLoader().getResourceAsStream("style.css");
 164                                 copy(in, resp.getWriter());
 165                                 resp.setContentType("text/css");
 166
 167                                 return ;
 168                         } catch (IOException e) {
 169                                 LOG.log(Level.SEVERE, "doGet failure", e);
 170                                 resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
 171
 172                                 return ;
 173                         }
 174                 }
 175
 176                 if (path.equals("/")) {
 177                         doTemporaryRedirect(config.getDefaultLanguage().toURL(), resp);
 178                         return ;
 179                 }
 180
 181                 try {
 182                         if (path.equals("/stats")) {
 183                                 writeStats(resp);
 184                                 return ;
 185                         }
 186
 187                         for (Category cat: config.getCategories()) {
 188                                 if (path.equals(cat.getURL())) {
 189                                         writeArticles(cat, getQueryParameter(req, "entity"), resp);
 190                                         return ;
 191                                 }
 192                         }
 193
 194                         for (Language l: config.getLanguages()) {
 195                                 if (path.equals(l.toURL())) {
 196                                         doTemporaryRedirect(config.getDefaultCategory(l).getURL(), resp);
 197                                         return ;
 198                                 }
 199                         }
 200
 201                         resp.getWriter().write("Not found " + req.getPathInfo());
 202                         resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
 203                 } catch (IOException | RuntimeException e) {
 204                         LOG.log(Level.SEVERE, "doGet failure", e);
 205                         resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
 206                 }
 207         }
 208
 209         @Override
 210         public void init(ServletConfig cfg) throws ServletException {
 211                 LOG.info("Pnews servlet init " + cfg.getServletContext().getContextPath());
 212
 213                 config = new Config();
 214                 try {
 215                         config.loadConfig();
 216                 } catch (UnsupportedEncodingException e) {
 217                         throw new ServletException(e);
 218                 }
 219
 220                 provider = new ArticleProvider(config);
 221         }
 222 }