com.yahoo.sql4d.query.select.SelectQueryMeta.java Source code

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Here is the source code for com.yahoo.sql4d.query.select.SelectQueryMeta.java

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/**
 * Copyright 2014 Yahoo! Inc. 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. 
 * See accompanying LICENSE file.
 */
package com.yahoo.sql4d.query.select;

import com.yahoo.sql4d.query.PlainDimQueryMeta;
import com.yahoo.sql4d.query.QueryMeta;
import com.yahoo.sql4d.query.RequestType;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import org.json.JSONArray;
import org.json.JSONObject;
import scala.Tuple2;

/**
 * {
"queryType": "select",
"dataSource": {
  "type": "table",
  "name": "SomeTable"
},
"dimensions": [],
"metrics": [],
"granularity": "all",
"intervals": [
  "2014-07-01/2014-07-02"
],
"pagingSpec": {
  "pagingIdentifiers": {},
  "threshold": 5
}
  }
    
 * @author srikalyan
 */
public class SelectQueryMeta extends PlainDimQueryMeta {

    public final PagingSpec pagingSpec = new PagingSpec(null, 5);
    public List<String> fetchMetrics = new ArrayList<>();

    private static final JSONObject EMPTY_JSON = new JSONObject();

    public SelectQueryMeta() {
        queryType = RequestType.SELECT;
    }

    public SelectQueryMeta(QueryMeta q) {
        super(q);
        queryType = RequestType.SELECT;
    }

    @Override
    public String toString() {
        return getJson().toString(2);
    }

    @Override
    public JSONObject getJson() {
        return new JSONObject(getJsonMap());
    }

    @Override
    public Map<String, Object> getJsonMap() {
        Map<String, Object> map = super.getJsonMap();
        Map<String, Object> pagingSpecMap = new LinkedHashMap<>();
        if (pagingSpec != null) {
            if (pagingSpec.pagingIdentifiers == null) {
                pagingSpecMap.put("pagingIdentifiers", EMPTY_JSON);
            } else {
                pagingSpecMap.put("pagingIdentifiers", pagingSpec.pagingIdentifiers);
            }
            pagingSpecMap.put("threshold", pagingSpec.threshold);
        }
        map.put("pagingSpec", pagingSpecMap);
        if (fetchMetrics != null) {
            map.put("metrics", new JSONArray(fetchMetrics));
        }
        return map;
    }

    /**
     * This method must be called prior to calling {@link SelectQueryMeta#getJsonMap() }.
     * Essentially splits columns into Dimensions and Metrics.
     * @param <T>
     * @param anyContext
     */
    @Override
    public <T> void postProcess(T anyContext) {
        Tuple2<List<String>, List<String>> dimsAndMetrics = (Tuple2<List<String>, List<String>>) anyContext;
        List<String> dims = dimsAndMetrics._1();
        List<String> metrics = dimsAndMetrics._2();
        Iterator<Map.Entry<String, String>> colIter = fetchDimensions.entrySet().iterator();
        while (colIter.hasNext()) {
            Map.Entry<String, String> entry = colIter.next();
            if (dims.contains(entry.getKey())) {
                //No action.
            } else if (metrics.contains(entry.getKey())) {
                fetchMetrics.add(entry.getKey());
                colIter.remove();
            } else {//TODO: Handle error

            }
        }
    }

    public static SelectQueryMeta promote(QueryMeta qMeta) {
        return new SelectQueryMeta(qMeta);
    }

}