com.francelabs.datafari.servlets.GetFieldsInfo.java Source code

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Here is the source code for com.francelabs.datafari.servlets.GetFieldsInfo.java

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/*******************************************************************************
 *  * Copyright 2015 France Labs
 *  *
 *  * Licensed 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 com.francelabs.datafari.servlets;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;
import org.apache.log4j.Logger;
import org.json.JSONArray;
import org.json.JSONObject;

import com.francelabs.datafari.utils.AdvancedSearchConfiguration;

/**
 * Servlet implementation class GetFieldsInfo
 *
 *
 * Has two return behaviors: - No fieldName param provided : return the list of
 * fields found in the schema.xml of Solr with their attributes (type, indexed,
 * etc) - fieldName param provided : return the field with his attributes if
 * found in the schema.xml
 *
 * The return format is a json containing the return code and the expected
 * result
 *
 */
@WebServlet("/GetFieldsInfo")
public class GetFieldsInfo extends HttpServlet {
    private static final long serialVersionUID = 1L;
    private static final Logger logger = Logger.getLogger(GetFieldsInfo.class.getName());

    /**
     * @see HttpServlet#HttpServlet()
     */
    public GetFieldsInfo() {

    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
     *      response)
     */
    @Override
    protected void doGet(final HttpServletRequest request, final HttpServletResponse response)
            throws ServletException, IOException {
        request.setCharacterEncoding("utf8");
        response.setContentType("application/json");
        final PrintWriter out = response.getWriter();

        try {
            // Define the Solr hostname, port and protocol
            final String solrserver = "localhost";
            final String solrport = "8983";
            final String protocol = "http";

            // Use Solr Schema REST API to get the list of fields
            final HttpClient httpClient = HttpClientBuilder.create().build();
            final HttpHost httpHost = new HttpHost(solrserver, Integer.parseInt(solrport), protocol);
            final HttpGet httpGet = new HttpGet("/solr/FileShare/schema/fields");
            final HttpResponse httpResponse = httpClient.execute(httpHost, httpGet);

            // Construct the jsonResponse
            final JSONObject jsonResponse = new JSONObject();
            if (httpResponse.getStatusLine().getStatusCode() == 200) {
                // Status of the API response is OK
                final JSONObject json = new JSONObject(EntityUtils.toString(httpResponse.getEntity()));
                final JSONArray fieldsJson = json.getJSONArray("fields");

                // Load the list of denied fields
                final String strDeniedFieldsList = AdvancedSearchConfiguration.getInstance()
                        .getProperty(AdvancedSearchConfiguration.DENIED_FIELD_LIST);
                final Set<String> deniedFieldsSet = new HashSet<>(Arrays.asList(strDeniedFieldsList.split(",")));

                for (int i = 0; i < fieldsJson.length(); i++) {
                    final JSONObject field = (JSONObject) fieldsJson.get(i);
                    // If a fieldname has been provided, it means that this
                    // servlet
                    // only
                    // needs to return infos on this specific field
                    if (request.getParameter("fieldName") != null) {
                        final String fieldName = request.getParameter("fieldName");
                        if (field.getString("name").equals(fieldName)) {
                            jsonResponse.append("field", field);
                            break;
                        }
                    } else {
                        if (!deniedFieldsSet.contains(field.getString("name"))
                                && (!field.has("indexed") || field.getBoolean("indexed"))
                                && !field.getString("name").startsWith("allow_")
                                && !field.getString("name").startsWith("deny_")
                                && !field.getString("name").startsWith("_")) {
                            jsonResponse.append("field", field);
                        }
                    }
                }

                out.print(jsonResponse);
            } else {
                // Status of the API response is an error
                logger.error("Error while retrieving the fields from the Schema API of Solr: "
                        + httpResponse.getStatusLine().toString());
                out.append(
                        "Error while retrieving the fields from the Schema API of Solr, please retry, if the problem persists contact your system administrator. Error Code : 69026");
            }
            out.close();
        } catch (final IOException e) {
            logger.error("Error while retrieving the fields from the Schema API of Solr", e);
            out.append(
                    "Error while retrieving the fields from the Schema API of Solr, please retry, if the problem persists contact your system administrator. Error Code : 69026");
            out.close();
        }

    }

}