watchdog/src/main/java/cz/senslog/watchdog/provider/ws/WebServiceDataProvider.java

package cz.senslog.watchdog.provider.ws;

import com.google.gson.reflect.TypeToken;
import cz.senslog.watchdog.config.WebServiceConfig;
import cz.senslog.watchdog.provider.DataProvider;
import cz.senslog.watchdog.provider.ObservationInfo;
import cz.senslog.watchdog.provider.Record;
import cz.senslog.watchdog.util.http.HttpClient;
import cz.senslog.watchdog.util.http.HttpRequest;
import cz.senslog.watchdog.util.http.HttpResponse;
import cz.senslog.watchdog.util.http.URLBuilder;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import java.lang.reflect.Type;
import java.time.OffsetDateTime;
import java.time.format.DateTimeFormatter;
import java.util.*;

import static cz.senslog.watchdog.util.json.BasicJson.jsonToObject;
import static java.time.format.DateTimeFormatter.ofPattern;

public class WebServiceDataProvider implements DataProvider {

    private static final Logger logger = LogManager.getLogger(WebServiceDataProvider.class);

    private static final DateTimeFormatter PATTERN = ofPattern("yyyy-MM-dd HH:mm:ssX");

    private final HttpClient httpClient = HttpClient.newHttpClient();
    private final WebServiceConfig config;

    public WebServiceDataProvider(WebServiceConfig config) {
        this.config = config;
    }

    @Override
    public List<Record> getLastRecords() {

        HttpRequest request = HttpRequest.newBuilder().GET()
                .url(URLBuilder.newBuilder(config.getUrl(), "/SensorService")
                        .addParam("Operation", "GetLastObservations")
                        .addParam("group", config.getGroup())
                        .addParam("user", config.getUser())
                        .build()
                ).build();

        HttpResponse response = httpClient.send(request);

        if (response.isOk()) {
            String jsonBody = response.getBody();
            Type lastObsType = new TypeToken<Collection<Map<String, Object>>>() {}.getType();
            List<Map<String, Object>> lastObservations = jsonToObject(jsonBody, lastObsType);
            List<Record> observations = new ArrayList<>(lastObservations.size());
            for (Map<String, Object> observationMap : lastObservations) {
                long unitId = ((Double)observationMap.get("unitId")).longValue();
                long sensorId = ((Double)observationMap.get("sensorId")).longValue();
                String timestampStr = observationMap.get("timeStamp").toString();
                OffsetDateTime timestamp = OffsetDateTime.parse(timestampStr, PATTERN);
                observations.add(new ObservationInfo(unitId, sensorId, timestamp));
            }
            return observations;
        } else {
            logger.error("code: {}, message: {}", response.getStatus(), response.getBody());
        }

        return Collections.emptyList();
    }

}