등락률 API 가공

package com.example.investment.home.fluctuation.controller.dto.response;

public record FluctuationDTO(
        String stockName, //HTS 한글 종목명
        int rank, //데이터(등락률) 순위
        int currentPrice, //현재가
        int prevChangePrice, //전일 대비
        String prevSign, //전일 대비 부호
        Double prevChangeRate //전일 대비율
) {
}

package com.example.investment.home.fluctuation.controller;

import com.example.investment.home.fluctuation.controller.dto.response.FluctuationDTO;
import com.example.investment.home.fluctuation.service.FluctuationService;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.io.IOException;
import java.util.List;

@RestController
@RequestMapping("home/fluctuation")
public class FluctuationController {

    private final FluctuationService fluctuationService;

    public FluctuationController(FluctuationService fluctuationService) {
        this.fluctuationService = fluctuationService;
    }

    @GetMapping
    public List<FluctuationDTO> getFluctuation() throws IOException {
        return fluctuationService.getFluctuation();
    }
}

package com.example.investment.home.fluctuation.infrastructor;

import com.example.investment.home.fluctuation.controller.dto.response.FluctuationDTO;

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

import org.springframework.stereotype.Component;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

@Component
public class FluctuationParser {

    private final ObjectMapper objectMapper;

    public FluctuationParser(final ObjectMapper objectMapper) {
        this.objectMapper = objectMapper;
    }

    public List<FluctuationDTO> getFluctuation(String responseBody) throws IOException {

        JsonNode rootNode = objectMapper.readTree(responseBody);
        JsonNode items = rootNode.path("output");

        List<FluctuationDTO> fluctuationDTOList = new ArrayList<>();
        Iterator<JsonNode> elements = items.elements();
        int count = 0;

        while (elements.hasNext() && count < 5) {

            JsonNode fluctuationItem = elements.next();

            String stockName = fluctuationItem.path("hts_kor_isnm").asText();

            int rank = Integer.parseInt(fluctuationItem.path("data_rank").asText());
            int currentPrice = Integer.parseInt(fluctuationItem.path("stck_prpr").asText());
            int prevChangePrice = Integer.parseInt(fluctuationItem.path("prdy_vrss").asText());

            String prevSign = fluctuationItem.path("prdy_vrss_sign").asText();
            Double prevChangeRate = Double.valueOf(fluctuationItem.path("prdy_ctrt").asText());

            fluctuationDTOList.add(new FluctuationDTO(stockName, rank, currentPrice, prevChangePrice, prevSign, prevChangeRate));
            count++;
        }

        return fluctuationDTOList;
    }

}

package com.example.investment.home.fluctuation.service.client;

import org.springframework.beans.factory.annotation.Value;

import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;

import org.springframework.stereotype.Component;

import org.springframework.web.client.RestTemplate;

@Component
public class FluctuationDataFetcher {

    private RestTemplate restTemplate;

    @Value("${api.app_key}")
    private String appKey;

    @Value("${api.app_secret}")
    private String appSecret;

    @Value("${fluctuation.tr_id}")
    private String trId;

    @Value("${api.access_token}")
    private String accessToken;

    public FluctuationDataFetcher(RestTemplate restTemplate) {
        this.restTemplate = restTemplate;
    }

    public ResponseEntity<String> fluctuationData() {
        String url = "https://openapi.koreainvestment.com:9443/uapi/domestic-stock/v1/ranking/fluctuation?"
                + "fid_cond_mrkt_div_code=J&"
                + "fid_cond_scr_div_code=20170&"
                + "fid_input_iscd=0000&"
                + "fid_rank_sort_cls_code=0&"
                + "fid_input_cnt_1=0&"
                + "fid_prc_cls_code=0&"
                + "fid_input_price_1=&"
                + "fid_input_price_2=&"
                + "fid_vol_cnt=&"
                + "fid_trgt_cls_code=0&"
                + "fid_trgt_exls_cls_code=0&"
                + "fid_div_cls_code=0&"
                + "fid_rsfl_rate1=&"
                + "fid_rsfl_rate2=";

        HttpHeaders headers = new HttpHeaders();

        headers.set("tr_id", trId);
        headers.set("appsecret", appSecret);
        headers.set("appkey", appKey);
        headers.set("Authorization", "Bearer " + accessToken);
        headers.set("Content-Type", "application/json");

        HttpEntity<String> entity = new HttpEntity<>(headers);

        return restTemplate.exchange(url, HttpMethod.GET, entity, String.class);
    }
}

package com.example.investment.home.fluctuation.service;


import com.example.investment.home.fluctuation.controller.dto.response.FluctuationDTO;
import com.example.investment.home.fluctuation.infrastructor.FluctuationParser;
import com.example.investment.home.fluctuation.service.client.FluctuationDataFetcher;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.io.IOException;
import java.util.List;

@Service
@Transactional
public class FluctuationService {

    private final FluctuationDataFetcher fluctuationDataFetcher;

    private final FluctuationParser fluctuationParser;

    @Autowired
    public FluctuationService(FluctuationDataFetcher fluctuationDataFetcher, FluctuationParser fluctuationParser) {
        this.fluctuationDataFetcher = fluctuationDataFetcher;
        this.fluctuationParser=fluctuationParser;
    }

    public List<FluctuationDTO> getFluctuation() throws IOException {
        ResponseEntity<String> response = fluctuationDataFetcher.fluctuationData();
        return fluctuationParser.getFluctuation(response.getBody());
    }
}