/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.sling.servlets.resolver.internal.helper;
import java.util.Iterator;
import java.util.Set;
import org.apache.commons.lang.ArrayUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.request.RequestPathInfo;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.servlets.resolver.internal.ServletResolverConstants;
import org.apache.sling.servlets.resolver.internal.resource.ServletResourceProviderFactory;
/**
* The <code>ResourceCollector</code> class provides a single public method -
* {@link #getServlets(ResourceResolver)} - which is used to find an ordered
* collection of <code>Resource</code> instances which may be used to find a
* servlet or script to handle a request to the given resource.
*/
public class ResourceCollector extends AbstractResourceCollector {
/**
* The special value returned by
* {@link #calculatePrefixMethodWeight(Resource, String, boolean)} if the
* resource is not suitable to handle the request according to the location
* prefix, request selectors and request extension (value is
* <code>Integer.MIN_VALUE</code>).
*/
protected static final int WEIGHT_NO_MATCH = Integer.MIN_VALUE;
// the request method name used to indicate the script name
private final String methodName;
// the request selectors as a string converted to a realtive path or
// null if the request has no selectors
private final String[] requestSelectors;
// the number of request selectors of the request or 0 if none
private final int numRequestSelectors;
// request is GET or HEAD
private final boolean isGet;
// request is GET or HEAD and extension is html
private final boolean isDefaultExtension;
private final String suffExt;
private final String suffMethod;
private final String suffExtMethod;
/**
* Creates a <code>ResourceCollector</code> for the given
* <code>request</code>. If the request is a GET or HEAD request, a
* specialized instance is returned which also takes the request selectors
* and request extension into account for finding servlet resources.
* Otherwise an instance of this class itself is returned which just takes
* the resource type and request method name into account.
*
* @param request The <code>SlingHttpServletRequest</code> for which to
* return a <code>ResourceCollector</code>.
* @return The <code>ResourceCollector</code> to find servlets and scripts
* suitable for handling the <code>request</code>.
*/
public static ResourceCollector create(
final SlingHttpServletRequest request,
final String[] executionPaths, final String[] defaultExtensions) {
final RequestPathInfo requestPathInfo = request.getRequestPathInfo();
final boolean isDefaultExtension = ArrayUtils.contains(defaultExtensions, requestPathInfo.getExtension());
return new ResourceCollector(request.getResource(), requestPathInfo.getExtension(), executionPaths, isDefaultExtension,
request.getMethod(), requestPathInfo.getSelectors());
}
public static ResourceCollector create(final Resource resource,
final String extension,
final String[] executionPaths, final String[] defaultExtensions,
final String methodName, final String[] selectors
) {
boolean isDefaultExtension = ArrayUtils.contains(defaultExtensions, extension);
return new ResourceCollector(resource, extension, executionPaths, isDefaultExtension, methodName, selectors);
}
/**
* Creates a <code>ResourceCollector</code> finding servlets and scripts for
* the given <code>methodName</code>.
*
* @param methodName The <code>methodName</code> used to find scripts for.
* This must not be <code>null</code>.
* @param baseResourceType The basic resource type to use as a final
* resource super type. If this is <code>null</code> the default
* value
* {@link org.apache.sling.servlets.resolver.internal.ServletResolverConstants#DEFAULT_SERVLET_NAME}
* is assumed.
* @param resource the resource to invoke, the resource type and resource
* super type are taken from this resource.
*/
public ResourceCollector(final String methodName,
final String baseResourceType, final Resource resource,
final String[] executionPaths) {
super((baseResourceType != null
? baseResourceType
: ServletResolverConstants.DEFAULT_SERVLET_NAME),
resource.getResourceType(), resource.getResourceSuperType(),
null, executionPaths);
this.methodName = methodName;
this.requestSelectors = new String[0];
this.numRequestSelectors = 0;
this.isGet = false;
this.isDefaultExtension = false;
this.suffExt = "." + extension;
this.suffMethod = "." + methodName;
this.suffExtMethod = suffExt + suffMethod;
// create the hash code once
final String key = methodName + ':' + baseResourceType + ':'
+ extension + "::"
+ (this.resourceType == null ? "" : this.resourceType) + ':'
+ (this.resourceSuperType == null ? "" : this.resourceSuperType);
this.hashCode = key.hashCode();
}
/**
* Creates a <code>ResourceCollector</code> finding servlets and scripts for
* the given <code>resource</code>.
*
* @param methodName The <code>methodName</code> used to find scripts for.
* This must not be <code>null</code>.
* @param baseResourceType The basic resource type to use as a final
* resource super type. If this is <code>null</code> the default
* value
* {@link org.apache.sling.servlets.resolver.internal.ServletResolverConstants#DEFAULT_SERVLET_NAME}
* is assumed.
*/
private ResourceCollector(final Resource resource,
final String extension,
final String[] executionPaths,
final boolean isDefaultExtension,
final String methodName,
final String[] selectors) {
super(ServletResolverConstants.DEFAULT_SERVLET_NAME,
resource.getResourceType(),
resource.getResourceSuperType(),
extension, executionPaths);
this.methodName = methodName;
this.suffExt = "." + extension;
this.suffMethod = "." + methodName;
this.suffExtMethod = suffExt + suffMethod;
this.requestSelectors = selectors;
this.numRequestSelectors = requestSelectors.length;
this.isGet = "GET".equals(methodName) || "HEAD".equals(methodName);
this.isDefaultExtension = isDefaultExtension;
// create the hash code once
final String key = methodName + ':' + baseResourceType + ':'
+ extension + ':' + StringUtils.join(requestSelectors, '.') + ':'
+ (this.resourceType == null ? "" : this.resourceType) + ':'
+ (this.resourceSuperType == null ? "" : this.resourceSuperType);
this.hashCode = key.hashCode();
}
@Override
protected void getWeightedResources(final Set<Resource> resources,
final Resource location) {
final ResourceResolver resolver = location.getResourceResolver();
Resource current = location;
String parentName = current.getName();
int selIdx = 0;
String selector;
do {
selector = (selIdx < numRequestSelectors)
? requestSelectors[selIdx]
: null;
Iterator<Resource> children = resolver.listChildren(current);
while (children.hasNext()) {
Resource child = children.next();
if (!this.isPathAllowed(child.getPath())) {
continue;
}
String scriptName = child.getName();
int lastDot = scriptName.lastIndexOf('.');
if (lastDot < 0) {
// no extension in the name, this is not a script
continue;
}
scriptName = scriptName.substring(0, lastDot);
if (isGet
&& checkScriptName(scriptName, selector, parentName,
suffExt, null, resources, child, selIdx)) {
continue;
}
if (checkScriptName(scriptName, selector, parentName,
suffExtMethod, suffMethod, resources, child, selIdx)) {
continue;
}
// SLING-754: Not technically really correct because
// the request extension is only optional in the script
// name for HTML methods, but we keep this for backwards
// compatibility.
if (selector != null
&& matches(scriptName, selector, suffMethod)) {
addWeightedResource(resources, child, selIdx + 1,
WeightedResource.WEIGHT_NONE);
continue;
}
if (scriptName.equals(methodName)) {
addWeightedResource(resources, child, selIdx,
WeightedResource.WEIGHT_NONE);
continue;
}
}
if (selector != null) {
current = resolver.getResource(current, selector);
parentName = selector;
selIdx++;
}
} while (selector != null && current != null);
// special treatment for servlets registered with neither a method
// name nor extensions and selectors
addLocationServlet(resources, location);
}
/**
* Checks whether the <code>scriptName</code> matches a certain number of
* combinations of <code>selector</code>, <code>parentName</code>,
* <code>suffix</code> and <code>htmlSuffix</code>. If a match is found the
* {@link #addWeightedResource(Set, Resource, int, int)} method is called to
* register the found script resource with appropriate selection weight.
*
* @param scriptName The name of the script (without the script extension)
* to check for compliance.
* @param selector The current selector to check for in the script name; may
* be <code>null</code>.
* @param parentName The name of the parent folder; must not be
* <code>null</code>.
* @param suffix Expected second part of the script name (besides either the
* selector or the parent name); must not be <code>null</code>;
* applicable for any request method.
* @param htmlSuffix Expected second part of the script name (besides either
* the selector or the parent name); may be <code>null</code>;
* applicable for GET or HEAD methods only.
* @param resources The set of weighted resource to which the new weighted
* resource is added if a match is found.
* @param child The resource representing the script
* @param selIdx The selector weight value
* @return <code>true</code> if a match has been found and a weighted
* resource has been added to the <code>resources</code> set.
*/
private boolean checkScriptName(final String scriptName,
final String selector, final String parentName,
final String suffix, final String htmlSuffix,
final Set<Resource> resources, final Resource child,
final int selIdx) {
if (selector != null && matches(scriptName, selector, suffix)) {
addWeightedResource(resources, child, selIdx + 1,
WeightedResource.WEIGHT_EXTENSION);
return true;
}
if (matches(scriptName, parentName, suffix)) {
addWeightedResource(resources, child, selIdx,
WeightedResource.WEIGHT_EXTENSION
+ WeightedResource.WEIGHT_PREFIX);
return true;
}
if (scriptName.equals(suffix.substring(1))) {
addWeightedResource(resources, child, selIdx,
WeightedResource.WEIGHT_EXTENSION);
return true;
}
if (isDefaultExtension) {
if (selector != null && matches(scriptName, selector, htmlSuffix)) {
addWeightedResource(resources, child, selIdx + 1,
WeightedResource.WEIGHT_NONE);
return true;
}
if (matches(scriptName, parentName, htmlSuffix)) {
addWeightedResource(resources, child, selIdx,
WeightedResource.WEIGHT_PREFIX);
return true;
}
}
return false;
}
private boolean matches(final String scriptName, final String name,
String suffix) {
if (suffix == null) {
return scriptName.equals(name);
}
final int lenScriptName = scriptName.length();
final int lenName = name.length();
final int lenSuffix = suffix.length();
return scriptName.regionMatches(0, name, 0, lenName)
&& scriptName.regionMatches(lenName, suffix, 0, lenSuffix)
&& lenScriptName == (lenName + lenSuffix);
}
private void addLocationServlet(final Set<Resource> resources,
final Resource location) {
final String path = location.getPath()
+ ServletResourceProviderFactory.SERVLET_PATH_EXTENSION;
if (this.isPathAllowed(path)) {
final Resource servlet = location.getResourceResolver().getResource(
path);
if (servlet != null) {
addWeightedResource(resources, servlet, 0,
WeightedResource.WEIGHT_LAST_RESSORT);
}
}
}
@Override
public boolean equals(Object obj) {
if (!(obj instanceof ResourceCollector)) {
return false;
}
if (obj == this) {
return true;
}
if (super.equals(obj)) {
final ResourceCollector o = (ResourceCollector) obj;
if (isGet == o.isGet && isDefaultExtension == o.isDefaultExtension
&& numRequestSelectors == o.numRequestSelectors
&& stringEquals(methodName, o.methodName)) {
// now compare selectors
for (int i = 0; i < numRequestSelectors; i++) {
if (!stringEquals(requestSelectors[i],
o.requestSelectors[i])) {
return false;
}
}
return true;
}
}
return false;
}
}