/*
* 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.compat.impl;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Properties;
import org.apache.felix.scr.annotations.Property;
import org.apache.felix.scr.annotations.Service;
import org.apache.sling.api.SlingException;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.SlingHttpServletResponse;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.api.resource.ResourceUtil;
import org.apache.sling.api.servlets.SlingSafeMethodsServlet;
import org.apache.sling.commons.json.JSONException;
import org.apache.sling.commons.json.io.JSONWriter;
import org.apache.sling.servlets.get.impl.helpers.JsonResourceWriter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A SlingSafeMethodsServlet that renders the search results as JSON data
*
* Use this as the default query servlet for json get requests for Sling
*/
@Component
@Service(value=javax.servlet.Servlet.class)
@Properties({
@Property(name="service.description", value="Default Query Servlet"),
@Property(name="service.vendor",value="The Apache Software Foundation"),
@Property(name="sling.servlet.resourceTypes", value="sling/servlet/default"),
@Property(name="sling.servlet.extensions", value="json"),
@Property(name="sling.servlet.selectors", value="query"),
@Property(name="sling.servlet.prefix", intValue=-1)
})
public class JsonQueryServlet extends SlingSafeMethodsServlet {
private static final long serialVersionUID = 1L;
private final Logger log = LoggerFactory.getLogger(JsonQueryServlet.class);
/** Search clause */
public static final String STATEMENT = "statement";
/** Query type */
public static final String QUERY_TYPE = "queryType";
/** Result set offset */
public static final String OFFSET = "offset";
/** Number of rows requested */
public static final String ROWS = "rows";
/** property to append to the result */
public static final String PROPERTY = "property";
/** exerpt lookup path */
public static final String EXCERPT_PATH = "excerptPath";
/** rep:exerpt */
private static final String REP_EXCERPT = "rep:excerpt()";
public static final String TIDY = "tidy";
private final JsonResourceWriter itemWriter;
public JsonQueryServlet() {
itemWriter = new JsonResourceWriter(null);
}
/** True if our request wants the "tidy" pretty-printed format */
protected boolean isTidy(SlingHttpServletRequest req) {
for(String selector : req.getRequestPathInfo().getSelectors()) {
if(TIDY.equals(selector)) {
return true;
}
}
return false;
}
@Override
protected void doGet(SlingHttpServletRequest req,
SlingHttpServletResponse resp) throws IOException {
dumpResult(req, resp);
}
/**
* Retrieve the query type from the request.
*
* @param req request
* @return the query type.
*
*/
protected String getQueryType(SlingHttpServletRequest req) {
return req.getParameter(QUERY_TYPE);
}
/**
* Retrieve the query statement from the request.
*
* @param req request
* @param queryType the query type, as previously determined
* @return the query statement.
*
*/
protected String getStatement(SlingHttpServletRequest req, String queryType) {
return req.getParameter(STATEMENT);
}
/**
* Dumps the result as JSON object.
*
* @param req request
* @param resp response
* @throws IOException in case the search will unexpectedly fail
*/
private void dumpResult(SlingHttpServletRequest req,
SlingHttpServletResponse resp) throws IOException {
try {
ResourceResolver resolver = req.getResourceResolver();
String queryType = getQueryType(req);
String statement = getStatement(req, queryType);
Iterator<Map<String, Object>> result = resolver.queryResources(
statement, queryType);
if (req.getParameter(OFFSET) != null) {
long skip = Long.parseLong(req.getParameter(OFFSET));
while (skip > 0 && result.hasNext()) {
result.next();
skip--;
}
}
resp.setContentType(req.getResponseContentType());
resp.setCharacterEncoding("UTF-8");
final JSONWriter w = new JSONWriter(resp.getWriter());
w.setTidy(isTidy(req));
w.array();
long count = -1;
if (req.getParameter(ROWS) != null) {
count = Long.parseLong(req.getParameter(ROWS));
}
List<String> properties = new ArrayList<String>();
if (req.getParameterValues(PROPERTY) != null) {
for (String property : req.getParameterValues(PROPERTY)) {
properties.add(property);
}
}
String exerptPath = "";
if (req.getParameter(EXCERPT_PATH) != null) {
exerptPath = req.getParameter(EXCERPT_PATH);
}
// iterate through the result set and build the "json result"
while (result.hasNext() && count != 0) {
Map<String, Object> row = result.next();
w.object();
String path = row.get("jcr:path").toString();
w.key("name");
w.value(ResourceUtil.getName(path));
// dump columns
for (String colName : row.keySet()) {
w.key(colName);
String strValue = "";
if (colName.equals(REP_EXCERPT)) {
Object ev = row.get("rep:excerpt(" + exerptPath + ")");
strValue = (ev == null) ? "" : ev.toString();
w.value(strValue);
} else {
//strValue = formatValue(row.get(colName));
itemWriter.dumpValue(w, row.get(colName));
}
//w.value(strValue);
}
// load properties and add it to the result set
if (!properties.isEmpty()) {
Resource nodeRes = resolver.getResource(path);
dumpProperties(w, nodeRes, properties);
}
w.endObject();
count--;
}
w.endArray();
} catch (JSONException je) {
throw wrapException(je);
}
}
private void dumpProperties(JSONWriter w, Resource nodeRes,
List<String> properties) throws JSONException {
// nothing to do if there is no resource
if (nodeRes == null) {
return;
}
itemWriter.dumpProperties(nodeRes, w, properties);
}
/**
* @param e
* @throws org.apache.sling.api.SlingException wrapping the given exception
*/
private SlingException wrapException(Exception e) {
log.warn("Error in QueryServlet: " + e.toString(), e);
return new SlingException(e.toString(), e);
}
}