/*
* 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.get;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.jcr.RepositoryException;
import javax.jcr.Value;
import javax.jcr.query.Query;
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.jcr.resource.JcrResourceUtil;
import org.apache.sling.servlets.get.helpers.JsonRendererServlet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A SlingSafeMethodsServlet that renders the search results as JSON data
*
* @scr.component immediate="true" metatype="no"
* @scr.service interface="javax.servlet.Servlet"
*
* @scr.property name="service.description" value="Default Query Servlet"
* @scr.property name="service.vendor" value="The Apache Software Foundation"
*
* Use this as the default query servlet for json get requests for Sling
* @scr.property name="sling.servlet.resourceTypes"
* value="sling/servlet/default"
* @scr.property name="sling.servlet.extensions" value="json"
* @scr.property name="sling.servlet.selectors" value="query"
*/
public class JsonQueryServlet extends SlingSafeMethodsServlet {
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()";
@Override
protected void doGet(SlingHttpServletRequest req,
SlingHttpServletResponse resp) throws IOException {
dumpResult(req, resp);
}
/**
* 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 statement = req.getParameter(STATEMENT);
String queryType = (req.getParameter(QUERY_TYPE) != null && req.getParameter(
QUERY_TYPE).equals(Query.SQL)) ? Query.SQL : Query.XPATH;
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(JsonRendererServlet.responseContentType);
resp.setCharacterEncoding("UTF-8");
final JSONWriter w = new JSONWriter(resp.getWriter());
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();
} else {
strValue = formatValue(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;
}
ResourceResolver resolver = nodeRes.getResourceResolver();
for (String property : properties) {
Resource prop = resolver.getResource(nodeRes, property);
if (prop != null) {
String strValue;
Value value = prop.adaptTo(Value.class);
if (value != null) {
strValue = formatValue(value);
} else {
strValue = prop.adaptTo(String.class);
if (strValue == null) {
strValue = "";
}
}
w.key(property);
w.value(strValue);
}
}
}
private String formatValue(Value value) {
try {
return formatValue(JcrResourceUtil.toJavaObject(value));
} catch (RepositoryException re) {
// might log
}
return "";
}
private String formatValue(Object value) {
String strValue;
if (value instanceof InputStream) {
// binary value comes as a LazyInputStream
strValue = "[binary]";
// just to be clean, close the stream
try {
((InputStream) value).close();
} catch (IOException ignore) {
}
} else if (value != null) {
strValue = value.toString();
} else {
strValue = "";
}
return strValue;
}
/**
* @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);
}
}