/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. 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. For additional information regarding
* copyright in this work, please see the NOTICE file in the top level
* directory of this distribution.
*/
package org.apache.abdera2.common.protocol;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.abdera2.common.misc.MoreFunctions;
import com.google.common.base.Function;
import com.google.common.collect.Iterables;
import com.google.common.collect.LinkedHashMultimap;
import com.google.common.collect.Multimap;
import static org.apache.abdera2.common.misc.MorePredicates.*;
/**
*
* Provides a utility class helpful for determining which type of resource the client is requesting. Each resource type
* (e.g. service doc, collection, entry, edit uri, media resource, etc) is assigned a regex pattern. Given the request
* URI (path and querystring), this will determine which resource was selected and return an appropriate TargetMatcher.
* TargetMatcher is essentially just a simplified version of the java.util.regex.Matcher that also specifies the
* Resource Type.
*
*
*
* RequestContext request = ...
* RegexTargetResolver tr = new RegexTargetResolver();
* tr.setPattern("/atom",ResourceType.INTROSPECTION)
* .setPattern("/atom/([^/#?]+)",ResourceType.COLLECTION)
* .setPattern("/atom/([^/#?]+)/([^/#?]+)",ResourceType.ENTRY)
* .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?edit",ResourceType.ENTRY_EDIT)
* .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?media",ResourceType.MEDIA)
* .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?edit-media",ResourceType.MEDIA_EDIT);
*
* Target target = tr.resolve(request);
* System.out.println(target.getType());
* System.out.println(targer.getParameter("foo"));
*
*/
public class RegexTargetResolver
implements Function {
protected final Map patterns;
protected final Multimap fields =
LinkedHashMultimap.create();
public RegexTargetResolver() {
this.patterns = new HashMap();
}
public RegexTargetResolver(Map patterns) {
this.patterns = new HashMap();
for (Map.Entry entry : patterns.entrySet())
setPattern(entry.getKey(), entry.getValue());
}
public RegexTargetResolver setPattern(String pattern, TargetType type) {
return setPattern(pattern, type, new String[0]);
}
public RegexTargetResolver setPattern(String pattern, TargetType type, String... fields) {
Pattern p = Pattern.compile(pattern);
this.patterns.put(p, type);
this.fields.putAll(p,Arrays.asList(fields));
return this;
}
public Target apply(R request) {
String uri = request.getTargetPath();
for (Pattern pattern : patterns.keySet()) {
Matcher matcher = pattern.matcher(uri);
if (matcher.matches())
return getTarget(
this.patterns.get(pattern),
request,
matcher,
this.fields.get(pattern));
}
return null;
}
protected Target getTarget(
TargetType type,
RequestContext request,
Matcher matcher,
Iterable fields) {
return new RegexTarget(type, request, matcher, fields);
}
public String toString() {
StringBuilder buf = new StringBuilder();
buf.append("Regex Target Resolver:\n");
for (Pattern pattern : patterns.keySet())
buf.append(
String.format(
"%s, Type: %s, Fields: %s",
pattern,
this.patterns.get(pattern),
this.fields.get(pattern)));
return buf.toString();
}
public int hashCode() {
return MoreFunctions.genHashCode(1, fields,patterns);
}
@SuppressWarnings("unchecked")
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
final RegexTargetResolver other = (RegexTargetResolver)obj;
if (fields == null) {
if (other.fields != null)
return false;
} else if (!fields.equals(other.fields))
return false;
if (patterns == null) {
if (other.patterns != null)
return false;
} else if (!patterns.equals(other.patterns))
return false;
return true;
}
public static class RegexTarget
extends SimpleTarget
implements Target {
private static final long serialVersionUID = 165211244926064449L;
protected Matcher matcher;
protected Iterable fields;
public RegexTarget(
TargetType type,
RequestContext context,
Matcher matcher,
Iterable fields) {
super(type, context);
this.matcher = matcher;
this.fields = fields;
}
public String getParameter(String name) {
if (fields == null)
return super.getParameter(name);
int idx = Iterables.indexOf(fields, equalsIgnoreCase(name));
return idx > -1 && idx <= matcher.groupCount()-1 ?
matcher.group(idx+1) : super.getParameter(name);
}
public Iterable getParameterNames() {
Iterable names = super.getParameterNames();
Set list = new HashSet();
for (String name : names)
list.add(name);
if (fields != null)
Iterables.addAll(list, fields);
return list;
}
@SuppressWarnings("unchecked")
@Override
public T getMatcher() {
return (T)matcher.pattern();
}
@Override
public int hashCode() {
String m = matcher.group(0);
String p = matcher.pattern().pattern();
return MoreFunctions.genHashCode(1, m,p,type);
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
final RegexTarget other = (RegexTarget)obj;
String m = matcher.group(0);
String p = matcher.pattern().pattern();
String m2 = other.matcher.group(0);
String p2 = other.matcher.pattern().pattern();
if (!super.equals(obj))
return false;
if (m == null) {
if (m2 != null)
return false;
} else if (!m.equals(m2))
return false;
if (p == null) {
if (p2 != null)
return false;
} else if (!p.equals(p2))
return false;
if (type == null) {
if (other.type != null)
return false;
} else if (!type.equals(other.type))
return false;
return true;
}
public String toString() {
String m = matcher.group(0);
String p = matcher.pattern().pattern();
StringBuilder buf = new StringBuilder();
buf.append("RegexTarget[").append(p).append(" ==> ").append(m).append("] = ").append(type.toString())
.append("\n");
for (String param : getParameterNames()) {
buf.append(" ").append(param).append(" = ").append(getParameter(param)).append("\n");
}
return buf.toString();
}
public String getIdentity() {
return context.getUri().toString();
}
}
}