binancej/src/main/java/com/sigmaflare/binancej/GeneralUtilities.java

package com.sigmaflare.binancej;

import com.sigmaflare.binancej.entities.ExchangeInfo;
import com.sigmaflare.binancej.entities.Ping;
import com.sigmaflare.binancej.entities.ServiceError;
import com.sigmaflare.binancej.entities.Time;
import com.sigmaflare.binancej.exceptions.BinanceServiceException;
import com.sigmaflare.binancej.exceptions.BinanceServiceUnreachableException;
import com.sigmaflare.binancej.exceptions.UnexpectedErrorException;
import lombok.Builder;
import org.apache.http.HttpEntity;
import org.apache.http.StatusLine;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.util.EntityUtils;

import java.io.IOException;

import static com.sigmaflare.binancej.Constant.NO_RESPONSE_TEXT_FORMATTED;
import static com.sigmaflare.binancej.HttpRequests.buildGetRequestFromEndpoint;

/**
 * GeneralUtilities is a container class for methods that interact with the infrastructure
 * on the Binance side. Methods like server health and exchange information are found here.
 */
public class GeneralUtilities extends BaseBinanceApi {
    private static final String PING_URL = "/api/v1/ping";
    private static final String TIME_URL = "/api/v1/time";
    private static final String EXCHANGE_INFO_URL = "/api/v1/exchangeInfo";

    @Builder
    public GeneralUtilities(String apiKey, String secretKey) {
        super(apiKey, secretKey);
    }

    GeneralUtilities(String apiKey, String secretKey, CloseableHttpClient closeableHttpClient) {
        super(apiKey, secretKey, closeableHttpClient);
    }


    /**
     * Hits the ping endpoint to check if the service is alive.
     *
     * @return Empty Ping object
     * @throws com.sigmaflare.binancej.exceptions.IpBannedException If the IP is banned
     * @throws com.sigmaflare.binancej.exceptions.RateLimitExceededException If the rate limit is exceeded
     * @throws com.sigmaflare.binancej.exceptions.MalformedRequestException If the user's request is malformed
     * @throws com.sigmaflare.binancej.exceptions.InternalServiceErrorException If the error occurs on Binance's side
     * @throws com.sigmaflare.binancej.exceptions.BinanceServiceUnreachableException If the service is unreachable
     * @throws UnexpectedErrorException If an unexpected exception occurs
     */
    public Ping ping() throws BinanceServiceException {
        final HttpGet request = buildGetRequestFromEndpoint(PING_URL, apiKey);

        try {
            try (CloseableHttpResponse closeableHttpResponse = closeableHttpClient.execute(request)) {
                StatusLine sl = closeableHttpResponse.getStatusLine();

                HttpEntity httpEntity = closeableHttpResponse.getEntity();

                if (httpEntity == null) {
                    throw new BinanceServiceUnreachableException(
                        String.format(NO_RESPONSE_TEXT_FORMATTED, request.getURI().toASCIIString()), null);
                }

                String response = EntityUtils.toString(httpEntity);

                if (!HttpRequests.statusCodeIsOk(sl.getStatusCode())) {
                    ServiceError error = mapper.readValue(response, ServiceError.class);
                    throw HttpRequests.buildHttpException(sl.getStatusCode(), error);
                }

                return new Ping();
            }
        } catch (IOException e) {
            throw new UnexpectedErrorException(e.getMessage(), e.getCause());
        }
    }

    /**
     * Gets the current server time on Binance's servers
     *
     * @return A Time object populated with the current server time
     * @throws com.sigmaflare.binancej.exceptions.IpBannedException If the IP is banned
     * @throws com.sigmaflare.binancej.exceptions.RateLimitExceededException If the rate limit is exceeded
     * @throws com.sigmaflare.binancej.exceptions.MalformedRequestException If the user's request is malformed
     * @throws com.sigmaflare.binancej.exceptions.InternalServiceErrorException If the error occurs on Binance's side
     * @throws com.sigmaflare.binancej.exceptions.BinanceServiceUnreachableException If the service is unreachable
     * @throws UnexpectedErrorException If an unexpected exception occurs
     */
    public Time getServerTime() throws BinanceServiceException {
        final HttpGet request = buildGetRequestFromEndpoint(TIME_URL, apiKey);

        try {
            try (CloseableHttpResponse closeableHttpResponse = closeableHttpClient.execute(request)) {
                StatusLine sl = closeableHttpResponse.getStatusLine();

                HttpEntity httpEntity = closeableHttpResponse.getEntity();

                if (httpEntity == null) {
                    throw new BinanceServiceUnreachableException(
                        String.format(NO_RESPONSE_TEXT_FORMATTED, request.getURI().toASCIIString()), null);
                }

                String response = EntityUtils.toString(httpEntity);

                if (!HttpRequests.statusCodeIsOk(sl.getStatusCode())) {
                    ServiceError error = mapper.readValue(response, ServiceError.class);
                    throw HttpRequests.buildHttpException(sl.getStatusCode(), error);
                }

                return mapper.readValue(response, Time.class);
            }
        } catch (IOException e) {
            throw new UnexpectedErrorException(e.getMessage(), e.getCause());
        }
    }

    /**
     * Retrieves exchange information
     *
     * @return An ExchangeInfo populated with exchange information
     * @throws com.sigmaflare.binancej.exceptions.IpBannedException If the IP is banned
     * @throws com.sigmaflare.binancej.exceptions.RateLimitExceededException If the rate limit is exceeded
     * @throws com.sigmaflare.binancej.exceptions.MalformedRequestException If the user's request is malformed
     * @throws com.sigmaflare.binancej.exceptions.InternalServiceErrorException If the error occurs on Binance's side
     * @throws com.sigmaflare.binancej.exceptions.BinanceServiceUnreachableException If the service is unreachable
     * @throws UnexpectedErrorException If an unexpected exception occurs
     */
    public ExchangeInfo getExchangeInfo() throws BinanceServiceException {
        final HttpGet request = buildGetRequestFromEndpoint(EXCHANGE_INFO_URL, apiKey);

        try {
            try (CloseableHttpResponse closeableHttpResponse = closeableHttpClient.execute(request)) {
                StatusLine sl = closeableHttpResponse.getStatusLine();

                HttpEntity httpEntity = closeableHttpResponse.getEntity();

                if (httpEntity == null) {
                    throw new BinanceServiceUnreachableException(
                        String.format(NO_RESPONSE_TEXT_FORMATTED, request.getURI().toASCIIString()), null);
                }

                String response = EntityUtils.toString(httpEntity);

                if (!HttpRequests.statusCodeIsOk(sl.getStatusCode())) {
                    ServiceError error = mapper.readValue(response, ServiceError.class);
                    throw HttpRequests.buildHttpException(sl.getStatusCode(), error);
                }

                return mapper.readValue(response, ExchangeInfo.class);
            }
        } catch (IOException e) {
            throw new UnexpectedErrorException(e.getMessage(), e.getCause());
        }
    }


}