/*
* Copyright (C) 2009-2010, Google Inc.
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
* available at http://www.eclipse.org/org/documents/edl-v10.php
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - 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.
*
* - Neither the name of the Eclipse Foundation, Inc. nor the
* names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
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*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
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* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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package org.eclipse.jgit.http.server.glue;
import static javax.servlet.http.HttpServletResponse.SC_NOT_FOUND;
import static org.eclipse.jgit.http.server.glue.MetaFilter.REGEX_GROUPS;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.servlet.Filter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Selects requests by matching the URI against a regular expression.
* <p>
* The pattern is bound and matched against the path info of the servlet
* request, as this class assumes it is invoked by {@link MetaServlet}.
* <p>
* If there are capture groups in the regular expression, the matched ranges of
* the capture groups are stored as an array of modified HttpServetRequests,
* into the request attribute {@link MetaFilter#REGEX_GROUPS}. Using a capture
* group that may not capture, e.g. {@code "(/foo)?"}, will cause an error at
* request handling time.
* <p>
* Each servlet request has been altered to have its {@code getServletPath()}
* method return the original path info up to the beginning of the corresponding
* capture group, and its {@code getPathInfo()} method return the matched text.
* A {@link RegexGroupFilter} can be applied in the pipeline to switch the
* current HttpServletRequest to reference a different capture group before
* running additional filters, or the final servlet.
* <p>
* Note that for {@code getPathInfo()} to start with a leading "/" as described
* in the servlet documentation, capture groups must actually capture the
* leading "/".
* <p>
* This class dispatches the remainder of the pipeline using the first capture
* group as the current request, making {@code RegexGroupFilter} required only
* to access capture groups beyond the first.
*/
class RegexPipeline extends UrlPipeline {
static class Binder extends ServletBinderImpl {
private final Pattern pattern;
Binder(final String p) {
pattern = Pattern.compile(p);
}
Binder(final Pattern p) {
pattern = p;
}
UrlPipeline create() {
return new RegexPipeline(pattern, getFilters(), getServlet());
}
}
private final Pattern pattern;
RegexPipeline(final Pattern pattern, final Filter[] filters,
final HttpServlet servlet) {
super(filters, servlet);
this.pattern = pattern;
}
boolean match(final HttpServletRequest req) {
final String pathInfo = req.getPathInfo();
return pathInfo != null && pattern.matcher(pathInfo).matches();
}
@Override
void service(HttpServletRequest req, HttpServletResponse rsp)
throws ServletException, IOException {
final String reqInfo = req.getPathInfo();
if (reqInfo == null) {
rsp.sendError(SC_NOT_FOUND);
return;
}
final Matcher cur = pattern.matcher(reqInfo);
if (!cur.matches()) {
rsp.sendError(SC_NOT_FOUND);
return;
}
final String reqPath = req.getServletPath();
final Object old = req.getAttribute(REGEX_GROUPS);
try {
if (1 <= cur.groupCount()) {
// If there are groups extract every capture group and
// build a request for them so RegexGroupFilter can pick
// a different capture group later. Continue using the
// first capture group as the path info.
WrappedRequest groups[] = new WrappedRequest[cur.groupCount()];
for (int groupId = 1; groupId <= cur.groupCount(); groupId++) {
final int s = cur.start(groupId);
final String path, info;
path = reqPath + reqInfo.substring(0, s);
info = cur.group(groupId);
groups[groupId - 1] = new WrappedRequest(req, path, info);
}
req.setAttribute(REGEX_GROUPS, groups);
super.service(groups[0], rsp);
} else {
// No capture groups were present, service the whole request.
final String path = reqPath + reqInfo;
final String info = null;
super.service(new WrappedRequest(req, path, info), rsp);
}
} finally {
if (old != null)
req.setAttribute(REGEX_GROUPS, old);
else
req.removeAttribute(REGEX_GROUPS);
}
}
@Override
public String toString() {
return "Pipeline[regex: " + pattern + " ]";
}
}