page/Page.java

   1 /*
   2  * shortener - Page.java - Copyright © 2010 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.sone.web.page;
  19
  20 import java.io.ByteArrayInputStream;
  21 import java.io.InputStream;
  22 import java.io.UnsupportedEncodingException;
  23 import java.net.URI;
  24 import java.util.HashMap;
  25 import java.util.Map;
  26
  27 import freenet.clients.http.ToadletContext;
  28 import freenet.support.api.HTTPRequest;
  29
  30 /**
  31  * A page is responsible for handling HTTP requests and creating appropriate
  32  * responses.
  33  *
  34  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  35  */
  36 public interface Page {
  37
  38         /**
  39          * Returns the path of this toadlet.
  40          *
  41          * @return The path of this toadlet
  42          */
  43         public String getPath();
  44
  45         /**
  46          * Handles a request.
  47          *
  48          * @param request
  49          *            The request to handle
  50          * @return The response
  51          */
  52         public Response handleRequest(Request request);
  53
  54         /**
  55          * Container for request data.
  56          *
  57          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  58          */
  59         public class Request {
  60
  61                 /**
  62                  * Enumeration for all possible HTTP request methods.
  63                  *
  64                  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’
  65                  *         Roden</a>
  66                  */
  67                 public enum Method {
  68
  69                         /** GET. */
  70                         GET,
  71
  72                         /** POST. */
  73                         POST,
  74
  75                         /** PUT. */
  76                         PUT,
  77
  78                         /** DELETE. */
  79                         DELETE,
  80
  81                         /** HEAD. */
  82                         HEAD,
  83
  84                         /** OPTIONS. */
  85                         OPTIONS,
  86
  87                         /** TRACE. */
  88                         TRACE,
  89
  90                 }
  91
  92                 /** The URI that was accessed. */
  93                 private final URI uri;
  94
  95                 /** The HTTP method that was used. */
  96                 private final Method method;
  97
  98                 /** The HTTP request. */
  99                 private final HTTPRequest httpRequest;
 100
 101                 /** The toadlet context. */
 102                 private final ToadletContext toadletContext;
 103
 104                 /**
 105                  * Creates a new request that holds the given data.
 106                  *
 107                  * @param uri
 108                  *            The URI of the request
 109                  * @param method
 110                  *            The HTTP method of the request
 111                  * @param httpRequest
 112                  *            The HTTP request
 113                  * @param toadletContext
 114                  *            The toadlet context of the request
 115                  */
 116                 public Request(URI uri, Method method, HTTPRequest httpRequest, ToadletContext toadletContext) {
 117                         this.uri = uri;
 118                         this.method = method;
 119                         this.httpRequest = httpRequest;
 120                         this.toadletContext = toadletContext;
 121                 }
 122
 123                 /**
 124                  * Returns the URI that was accessed.
 125                  *
 126                  * @return The accessed URI
 127                  */
 128                 public URI getUri() {
 129                         return uri;
 130                 }
 131
 132                 /**
 133                  * Returns the HTTP method that was used to access the page.
 134                  *
 135                  * @return The HTTP method
 136                  */
 137                 public Method getMethod() {
 138                         return method;
 139                 }
 140
 141                 /**
 142                  * Returns the HTTP request.
 143                  *
 144                  * @return The HTTP request
 145                  */
 146                 public HTTPRequest getHttpRequest() {
 147                         return httpRequest;
 148                 }
 149
 150                 /**
 151                  * Returns the toadlet context.
 152                  *
 153                  * @return The toadlet context
 154                  */
 155                 public ToadletContext getToadletContext() {
 156                         return toadletContext;
 157                 }
 158
 159         }
 160
 161         /**
 162          * Container for the HTTP response of a {@link Page}.
 163          *
 164          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 165          */
 166         public class Response {
 167
 168                 /** The HTTP status code of the response. */
 169                 private final int statusCode;
 170
 171                 /** The HTTP status text of the response. */
 172                 private final String statusText;
 173
 174                 /** The content type of the response. */
 175                 private final String contentType;
 176
 177                 /** The headers of the response. */
 178                 private final Map<String, String> headers;
 179
 180                 /** The content of the response body. */
 181                 private final InputStream content;
 182
 183                 /**
 184                  * Creates a new response.
 185                  *
 186                  * @param statusCode
 187                  *            The HTTP status code of the response
 188                  * @param statusText
 189                  *            The HTTP status text of the response
 190                  * @param contentType
 191                  *            The content type of the response
 192                  * @param text
 193                  *            The text in the response body
 194                  */
 195                 public Response(int statusCode, String statusText, String contentType, String text) {
 196                         this(statusCode, statusText, contentType, getBytes(text));
 197                 }
 198
 199                 /**
 200                  * Creates a new response.
 201                  *
 202                  * @param statusCode
 203                  *            The HTTP status code of the response
 204                  * @param statusText
 205                  *            The HTTP status text of the response
 206                  * @param contentType
 207                  *            The content type of the response
 208                  * @param content
 209                  *            The content of the reponse body
 210                  */
 211                 public Response(int statusCode, String statusText, String contentType, byte[] content) {
 212                         this(statusCode, statusText, contentType, new HashMap<String, String>(), content);
 213                 }
 214
 215                 /**
 216                  * Creates a new response.
 217                  *
 218                  * @param statusCode
 219                  *            The HTTP status code of the response
 220                  * @param statusText
 221                  *            The HTTP status text of the response
 222                  * @param contentType
 223                  *            The content type of the response
 224                  * @param headers
 225                  *            The headers of the response
 226                  */
 227                 public Response(int statusCode, String statusText, String contentType, Map<String, String> headers) {
 228                         this(statusCode, statusText, contentType, headers, (InputStream) null);
 229                 }
 230
 231                 /**
 232                  * Creates a new response.
 233                  *
 234                  * @param statusCode
 235                  *            The HTTP status code of the response
 236                  * @param statusText
 237                  *            The HTTP status text of the response
 238                  * @param contentType
 239                  *            The content type of the response
 240                  * @param headers
 241                  *            The headers of the response
 242                  * @param content
 243                  *            The content of the reponse body
 244                  */
 245                 public Response(int statusCode, String statusText, String contentType, Map<String, String> headers, byte[] content) {
 246                         this(statusCode, statusText, contentType, headers, new ByteArrayInputStream(content));
 247                 }
 248
 249                 /**
 250                  * Creates a new response.
 251                  *
 252                  * @param statusCode
 253                  *            The HTTP status code of the response
 254                  * @param statusText
 255                  *            The HTTP status text of the response
 256                  * @param contentType
 257                  *            The content type of the response
 258                  * @param headers
 259                  *            The headers of the response
 260                  * @param content
 261                  *            The content of the reponse body
 262                  */
 263                 public Response(int statusCode, String statusText, String contentType, Map<String, String> headers, InputStream content) {
 264                         this.statusCode = statusCode;
 265                         this.statusText = statusText;
 266                         this.contentType = contentType;
 267                         this.headers = headers;
 268                         this.content = content;
 269                 }
 270
 271                 /**
 272                  * Returns the HTTP status code of the response.
 273                  *
 274                  * @return The HTTP status code
 275                  */
 276                 public int getStatusCode() {
 277                         return statusCode;
 278                 }
 279
 280                 /**
 281                  * Returns the HTTP status text.
 282                  *
 283                  * @return The HTTP status text
 284                  */
 285                 public String getStatusText() {
 286                         return statusText;
 287                 }
 288
 289                 /**
 290                  * Returns the content type of the response.
 291                  *
 292                  * @return The content type of the reponse
 293                  */
 294                 public String getContentType() {
 295                         return contentType;
 296                 }
 297
 298                 /**
 299                  * Returns HTTP headers of the response. May be {@code null} if no
 300                  * headers are returned.
 301                  *
 302                  * @return The response headers, or {@code null} if there are no
 303                  *         response headers
 304                  */
 305                 public Map<String, String> getHeaders() {
 306                         return headers;
 307                 }
 308
 309                 /**
 310                  * Sets the HTTP header with the given name to the given value. Multiple
 311                  * headers with the same name are not implemented so that latest call to
 312                  * {@link #setHeader(String, String)} determines what is sent to the
 313                  * browser.
 314                  *
 315                  * @param name
 316                  *            The name of the header
 317                  * @param value
 318                  *            The value of the header
 319                  */
 320                 public void setHeader(String name, String value) {
 321                         headers.put(name, value);
 322                 }
 323
 324                 /**
 325                  * Returns the content of the response body. May be {@code null} if the
 326                  * response does not have a body.
 327                  *
 328                  * @return The content of the response body
 329                  */
 330                 public InputStream getContent() {
 331                         return content;
 332                 }
 333
 334                 //
 335                 // PRIVATE METHODS
 336                 //
 337
 338                 /**
 339                  * Returns the UTF-8 representation of the given text.
 340                  *
 341                  * @param text
 342                  *            The text to encode
 343                  * @return The encoded text
 344                  */
 345                 private static byte[] getBytes(String text) {
 346                         try {
 347                                 return text.getBytes("UTF-8");
 348                         } catch (UnsupportedEncodingException uee1) {
 349                                 /* every JVM needs to support UTF-8. */
 350                         }
 351                         return null;
 352                 }
 353
 354                 /**
 355                  * Creates a header map containing a single header.
 356                  *
 357                  * @param name
 358                  *            The name of the header
 359                  * @param value
 360                  *            The value of the header
 361                  * @return The map containing the single header
 362                  */
 363                 protected static Map<String, String> createHeader(String name, String value) {
 364                         Map<String, String> headers = new HashMap<String, String>();
 365                         headers.put(name, value);
 366                         return headers;
 367                 }
 368
 369         }
 370
 371         /**
 372          * {@link Response} implementation that performs an HTTP redirect.
 373          *
 374          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 375          */
 376         public class RedirectResponse extends Response {
 377
 378                 /**
 379                  * Creates a new redirect response to the new location.
 380                  *
 381                  * @param newLocation
 382                  *            The new location
 383                  */
 384                 public RedirectResponse(String newLocation) {
 385                         this(newLocation, true);
 386                 }
 387
 388                 /**
 389                  * Creates a new redirect response to the new location.
 390                  *
 391                  * @param newLocation
 392                  *            The new location
 393                  * @param permanent
 394                  *            Whether the redirect should be marked as permanent
 395                  */
 396                 public RedirectResponse(String newLocation, boolean permanent) {
 397                         super(permanent ? 302 : 307, "Redirected", null, createHeader("Location", newLocation));
 398                 }
 399
 400         }
 401
 402 }