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/*
* TemplateHandler.java
*
* Brazil project web application toolkit,
* export version: 2.3
* Copyright (c) 1998-2007 Sun Microsystems, Inc.
*
* Sun Public License Notice
*
* The contents of this file are subject to the Sun Public License Version
* 1.0 (the "License"). You may not use this file except in compliance with
* the License. A copy of the License is included as the file "license.terms",
* and also available at http://www.sun.com/
*
* The Original Code is from:
* Brazil project web application toolkit release 2.3.
* The Initial Developer of the Original Code is: suhler.
* Portions created by suhler are Copyright (C) Sun Microsystems, Inc.
* All Rights Reserved.
*
* Contributor(s): cstevens, drach, suhler.
*
* Version: 2.8
* Created by suhler on 98/09/14
* Last modified by suhler on 07/01/08 15:15:18
*
* Version Histories:
*
* 2.8 07/01/08-15:15:18 (suhler)
* set the last-modified property
*
* 2.7 06/11/13-15:00:12 (suhler)
* move MatchString from handler -> util
*
* 2.6 06/04/25-14:16:39 (suhler)
* use consolidated mime type handling in FileHandler
*
* 2.5 04/12/30-12:38:25 (suhler)
* javadoc fixes
*
* 2.4 04/10/24-17:21:47 (suhler)
* bug fix. change "FileName" to "fileName"
*
* 2.3 03/08/01-16:19:06 (suhler)
* fixes for javadoc
*
* 2.2 03/07/14-09:57:42 (suhler)
* added tagPrefix option docs
*
* 2.1 02/10/01-16:36:47 (suhler)
* version change
*
* 1.42 02/08/21-15:33:51 (suhler)
* add "outputEncoding" support
*
* 1.41 02/06/27-18:38:11 (suhler)
* add encoding option
*
* 1.40 02/06/24-15:40:14 (suhler)
* Don't install the template handler is one of the templates fails
*
* 1.39 02/05/24-16:58:22 (suhler)
* add "modified" option to output last-modified times
*
* 1.38 02/04/24-13:36:11 (suhler)
* check for text mime type before processing
*
* 1.37 02/04/24-12:53:00 (suhler)
* check for (and reject) non-text mime types
*
* 1.36 01/12/07-14:26:28 (suhler)
* 'twas quite broken:
* - use MatchString instead of old prefix/suffix matching
* - fixed redirects and suffix checking, so that this handler may be
* - used by itself.
*
* 1.35 01/08/14-16:39:09 (suhler)
* any status code changes were being inadvertantly reset
*
* 1.34 01/05/02-15:32:06 (drach)
* Add template tokens.
*
* 1.33 01/03/06-09:07:53 (suhler)
* make sure specified suffix maps to a valid mime type
*
* 1.32 00/12/11-13:30:04 (suhler)
* add class=props for automatic property extraction
*
* 1.31 00/11/28-10:09:34 (suhler)
* changed log level
*
* 1.30 00/10/25-20:16:45 (suhler)
* Session handling was broken: was not finding session id properly
* .
*
* 1.29 00/10/20-15:42:31 (suhler)
* api change due to race condition in TemplateRunner
*
* 1.28 00/07/05-14:11:11 (cstevens)
* Server object is in RewriteContext used by templates, so templates (such as
* the TclServerTemplate) can be initialized with the server and prefix, similar
* to how Handlers are initialized.
*
* 1.27 00/05/31-13:50:06 (suhler)
* use standard "null" session
*
* 1.26 00/05/22-14:06:02 (suhler)
* add redirects and default handling ala the file handler
*
* 1.25 00/05/15-10:13:51 (suhler)
* added diags
*
* 1.24 00/05/12-10:58:01 (suhler)
* - removed all cookie header processing:
* use a session handler instead
* - Only filte system templates are supported. Removed uncocumented
* "handler" option
* - fixed documentation
*
* 1.23 00/04/17-14:25:23 (cstevens)
* TemplateHandler.java, TemplateFilter.java:
* 1. configuration property "templateClass" -> "templates"
*
* 1.22 00/03/29-16:15:53 (cstevens)
* clean TemplateHandler.
*
* 1.21 00/02/01-19:01:27 (suhler)
* missing close()
*
* 1.20 00/01/03-13:37:26 (suhler)
* fixes
*
* 1.19 00/01/03-13:29:06 (suhler)
* redo removing use of file handler
*
* 1.18 99/12/09-10:42:36 (suhler)
* re-added old fileHandler hack
*
* 1.17 99/11/16-19:07:59 (cstevens)
* wildcard imports
*
* 1.16 99/10/28-17:23:02 (cstevens)
* ChangedTemplate
*
* 1.15 99/10/25-15:36:41 (cstevens)
* propsPrefix to pref
*
* 1.14 99/10/21-18:14:10 (cstevens)
* TemplateHandler now takes a list of Templates, rather than just one. When
* parsing an HTML file, it will now dispatch to the union of all the tag
* methods defined in the list of Templates. In that way, the user can
* compose things like the BSLTemplate to iterate over request properties with
* the PropsTemplate to substitute in their values. Otherwise, it would have
* required N separate passes (via N separate TemplateHandlers) over the HTML
* file, one for each Template and/or level of recursion in the BSLTemplate.
*
* 1.13 99/10/01-11:26:46 (cstevens)
* Change logging to show prefix of Handler generating the log message.
*
* 1.12 99/09/29-16:05:54 (cstevens)
* New HtmlRewriter object, that allows arbitrary rewriting of the HTML (by
* templates and others), instead of forcing the templates to return a string
* that contained all of the new HTML content in one big string.
*
* 1.11 99/06/28-10:50:07 (suhler)
* ???
*
* 1.10 99/05/24-18:24:46 (suhler)
* fixed wildcard imports
*
* 1.9 99/05/24-17:38:07 (suhler)
* rewritten to use new template class
* (the timing is unfortunate)
*
* 1.8 99/05/13-09:22:28 (suhler)
* modified to use new no-dilimeter option of HtmlMunge
*
* 1.7 99/03/30-09:30:59 (suhler)
* documentation update
*
* 1.6 99/02/19-15:44:47 (suhler)
* If the cookie name "none" is supplied as a property, then no cookies are
* used, and every client gets the same object.
*
* 1.5 98/11/30-15:47:07 (suhler)
* Rearranged code to permit subclassing for server-side xml processing
*
* 1.4 98/10/13-08:09:41 (suhler)
* don't import self
*
* 1.3 98/09/21-14:55:04 (suhler)
* changed the package names
*
* 1.2 98/09/20-15:38:14 (suhler)
* removed *'s imports
*
* 1.2 98/09/14-18:03:12 (Codemgr)
* SunPro Code Manager data about conflicts, renames, etc...
* Name history : 3 2 handlers/templates/TemplateHandler.java
* Name history : 2 1 handlers/TemplateHandler.java
* Name history : 1 0 TemplateHandler.java
*
* 1.1 98/09/14-18:03:11 (suhler)
* date and time created 98/09/14 18:03:11 by suhler
*
*/
package sunlabs.brazil.template;
import sunlabs.brazil.util.MatchString;
import sunlabs.brazil.server.FileHandler;
import sunlabs.brazil.server.Handler;
import sunlabs.brazil.server.Request;
import sunlabs.brazil.server.Server;
import sunlabs.brazil.util.http.HttpUtil;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Properties;
/**
* The TemplateHandler reads a template file from
* the document root, based on the URL, and passes the content through
* one or more template filters.
*
* The following configuration parameters are used to initialize this
* Handler:
* - prefix, suffix, glob, match
*
- Specify the URL that triggers this handler.
* By default, all URL's are considered.
* Only documents that are mime sub-types of
text
* are processed. See {@link sunlabs.brazil.server.FileHandler} for a
* description of how to set mime types for url suffixes.
* (See {@link MatchString}).
* -
templates
* - A list of template names. For each name in the list, the property
*
name.class is examined to determine which class to
* use for each template. Then name is used as the prefix
* for other template specific properties if any. If
* name.class does not exist, then name
* is assumed to be the class name, and there are no template specific
* properties for the template. Methods in the template classes will be
* invoked to process the XML/HTML tags present in the content.
* -
session
* - The name of the request property that the Session ID will be found
* in, used to identify the proper template instance.
* The default value is "SessionID". Typically, a sessionHandler,
* such as {@link sunlabs.brazil.handler.CookieSessionHandler} is used
* upstream to create the sessionID. If no id is found, then the
* session named "common" is used instead. Exactly one instance of
* each template class is created for each session.
*
-
default
* - The default file in the directory to use as a template if
* a directory name is specified. Defaults to index[suffix],
* or "index.html" if no suffix is provided.
*
-
encoding
* - The character encoding to use to interpret the template.
* If no encoding is specified, the default encoding is used.
* The template is read from the filesystem, and converted into a
* String using this encoding. All template processing is done
* using the String representation.
*
-
outputEncoding
* - The character encoding to use to interpret the template results.
* If no "outputEncoding" is specified, then "encoding" is used.
* Once template processing is complete, the results are converted
* into a byte stream for transmission to the client using the
* "outputEncoding", if specified. If not specified then the HTTP
* default (8-bit ASCII) encoding is used.
*
-
modified
* - if present (e.g. set to any value) an HTTP
* last-modified header is added to the response with the
* current time.
* -
debug
* if set to "true", template debugging is enabled: templates will emit
* their pre-processed markup as an HTML comment. This parameter only takes effect
* if the debug option is not specified for an individual template.
* -
*
-
tagPrefix
* - If specified, all tag names defined for each template class
* are prefixed with tagPrefix.
* This parameter only takes effect
* if the
tagPrefix option is not specified for an individual template.
* -
*
* The request properties DirectoryName,
* fileName and lastModified may be
* set as a convenience for downstream handlers.
*
* This handler duplicates some of the functionality of the
* {@link sunlabs.brazil.handler.DefaultFileHandler template filter},
* so that it may be used by itself in simple configurations. As such,
* if issues re-directs if directories are given without a trailing "/",
* and uses an "index" file (see default above) if a directory
* name is specified.
*
* To filter content other than from the file system, use the
* {@link sunlabs.brazil.filter.TemplateFilter template filter} instead.
*
* @author Stephen Uhler ([email protected])
* @author Colin Stevens ([email protected])
* @version 2.8 07/01/08
*/
public class TemplateHandler implements Handler {
static final String HANDLER = "handler";
static final String TEMPLATES = "templates"; // the class to process these templates
static final String SESSION = "session";
static final String ENCODING = "encoding";
static final String DEFAULT = "default"; // property for default document, given directory
String propsPrefix; // our perfix in the config file
String sessionProperty; // where to find the session name
MatchString isMine; // check for matching url
boolean modified; // if set, emit last-modified header
String encoding; // the page character encoding
Handler handler;
TemplateRunner runner; // The template object for our class
public boolean
init(Server server, String propsPrefix) {
this.propsPrefix = propsPrefix;
isMine = new MatchString(propsPrefix, server.props);
Properties props = server.props;
sessionProperty = props.getProperty(propsPrefix + SESSION, "SessionID");
encoding = props.getProperty(propsPrefix + ENCODING);
modified = (props.getProperty(propsPrefix + "modified") != null);
/*
* Gather the templates.
*/
String str;
str = server.props.getProperty(propsPrefix + TEMPLATES);
if (str == null) {
server.log(Server.LOG_ERROR, propsPrefix,
"no " + TEMPLATES + " property specified");
return false;
}
try {
runner = new TemplateRunner(server, propsPrefix, str);
} catch (ClassCastException e) {
server.log(Server.LOG_ERROR, e.getMessage(), "not a Template");
return false;
} catch (ClassNotFoundException e) {
server.log(Server.LOG_ERROR, e.getMessage(), "unknown class");
return false;
}
return true;
}
/**
* Process an html template file, using the supplied template
* processing classes.
*/
public boolean
respond(Request request) throws IOException {
if (!isMine.match(request.url)) {
return false;
}
Properties props = request.props;
String root = props.getProperty(propsPrefix + FileHandler.ROOT,
props.getProperty(FileHandler.ROOT, "."));
String name = FileHandler.urlToPath(request.url);
File file = new File(root + name);
String path = file.getPath();
String outputEncoding = props.getProperty(propsPrefix +
"outputEncoding", encoding);
/*
* XXX This doesn't belong here. The DefaultFileHandler should
* be used instead. This allows "simple" configurations using only
* this handler.
*/
if (file.isDirectory()) {
if (request.url.endsWith("/") == false) {
request.redirect(request.url + "/", null);
return true;
}
props.put("DirectoryName", path);
String index = props.getProperty(propsPrefix+DEFAULT, "index.html");
file = new File(file, index);
path = file.getPath();
}
props.put("fileName", path);
request.log(Server.LOG_DIAGNOSTIC, propsPrefix,
"Looking for template file: " + path);
int index = path.lastIndexOf('.');
if (index < 0) {
request.log(Server.LOG_INFORMATIONAL, propsPrefix,
"no file suffix for: " + path);
return false;
}
String type = FileHandler.getMimeType(path, props, propsPrefix);
if (type == null) {
request.log(Server.LOG_INFORMATIONAL, propsPrefix,
"unknown file suffix for: " + path);
return false;
}
// make sure this is a text file!
if (!type.toLowerCase().startsWith("text/")) {
request.log(Server.LOG_INFORMATIONAL, propsPrefix,
"Not a text file: " + type);
return false;
}
// OK, now we can read in the file!
String content;
try {
content = getContent(request, file, encoding);
} catch (IOException e) {
request.log(Server.LOG_WARNING, propsPrefix, e.getMessage());
return false;
}
String session = props.getProperty(sessionProperty, "common");
request.log(Server.LOG_DIAGNOSTIC, propsPrefix,
"Using session (" + session + ")");
String result = runner.process(request, content, session);
if (result != null) {
if (modified) {
request.addHeader("Last-Modified", HttpUtil.formatTime());
}
FileHandler.setModified(request.props,file.lastModified());
if (outputEncoding == null) {
request.sendResponse(result, type);
} else {
request.sendResponse(result.getBytes(outputEncoding),
type + "; charset=" + outputEncoding);
}
return true;
} else {
request.log(Server.LOG_INFORMATIONAL,propsPrefix,runner.getError());
return false;
}
}
/**
* get the content associated with this template.
* This version reads it from a file.
*
* @param request The standard request object
* @param file The file object to get the template from
* @return The content of the template to be processed
*/
public String
getContent(Request request, File file, String encoding) throws IOException {
FileInputStream in = new FileInputStream(file);
byte[] buf = new byte[in.available()];
in.read(buf);
in.close();
String result;
if (encoding != null) {
result = new String(buf, encoding);
} else {
result = new String(buf);
}
return result;
}
}