org.springframework.cloud.stream.app.yahoo.quotes.source.YahooQuotesClientImpl.java Source code

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Here is the source code for org.springframework.cloud.stream.app.yahoo.quotes.source.YahooQuotesClientImpl.java

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/*
 *  Copyright 2016 original author or authors.
 *
 *  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 org.springframework.cloud.stream.app.yahoo.quotes.source;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.springframework.http.ResponseEntity;
import org.springframework.util.StringUtils;
import org.springframework.web.client.RestTemplate;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

/**
 * @author Vinicius Carvalho
 */
public class YahooQuotesClientImpl implements YahooQuotesClient {

    private final String endpoint = "https://query.yahooapis.com/v1/public/yql?q={query}&format=json&env={env}&callback=";

    private final String queryTemplate = "select %s from yahoo.finance.quotes(%d) where symbol in (%s)";

    private RestTemplate client;

    private ObjectMapper mapper = new ObjectMapper();

    final DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssX");

    public YahooQuotesClientImpl(RestTemplate client) {
        this.client = client;
    }

    @Override
    public List<Map<String, Object>> fetchQuotes(List<String> symbols, String filter) {
        String fields = (StringUtils.isEmpty(filter)) ? "*" : filter;
        String query = String.format(queryTemplate, fields, symbols.size(), wouldbeSimplerWithLambdas(symbols));
        Map<String, String> vars = new HashMap<>();
        vars.put("query", query);
        vars.put("env", "store://datatables.org/alltableswithkeys");
        ResponseEntity<JsonNode> response = client.getForEntity(endpoint, JsonNode.class, vars);
        return processResponse(response);
    }

    private List<Map<String, Object>> processResponse(ResponseEntity<JsonNode> response) {
        if (!response.getStatusCode().is2xxSuccessful())
            return Collections.emptyList();
        String timestamp = df.format(new Date());
        JsonNode node = response.getBody();
        JsonNode resultsNode = node.get("query").get("results").get("quote");
        List<Map<String, Object>> results = new LinkedList<>();
        if (resultsNode.isArray()) {
            for (JsonNode child : resultsNode) {
                ((ObjectNode) child).put("timestamp", timestamp);
                results.add(mapper.convertValue(child, Map.class));
            }
        } else {
            ((ObjectNode) resultsNode).put("timestamp", timestamp);
            results.add(mapper.convertValue(resultsNode, Map.class));
        }
        return results;
    }

    private String wouldbeSimplerWithLambdas(List<String> symbols) {
        for (int i = 0; i < symbols.size(); i++) {
            if (!symbols.get(i).startsWith("'") && !symbols.get(i).startsWith("\\"))
                symbols.set(i, StringUtils.quote(symbols.get(i)));
        }
        return StringUtils.collectionToCommaDelimitedString(symbols);
    }
}