D-Net

package eu.dnetlib.repo.manager.utils;

import com.google.gson.JsonElement;

import com.google.gson.JsonObject;

import com.google.gson.JsonParser;

import org.apache.commons.codec.binary.Base64;

import org.apache.log4j.Logger;

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

import org.springframework.http.*;

import org.springframework.stereotype.Component;

import org.springframework.web.client.RestTemplate;

import java.nio.charset.Charset;

import java.util.Map;

@Component

public class HttpUtils {

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

    @Value("${aai.registry.url}")

    private String registryUrl;

    @Value("${aai.registry.authentication.username}")

    private String user;

    @Value("${aai.registry.authentication.password}")

    private String password;

    public JsonElement post(String path, JsonObject body) {

        RestTemplate restTemplate = new RestTemplate();

        HttpHeaders headers = createHeaders(user, password);

        headers.setContentType(MediaType.APPLICATION_JSON);

        HttpEntity<String> request = new HttpEntity<>(body.toString(), headers);

        ResponseEntity<String> responseEntity = restTemplate.exchange(registryUrl + path, HttpMethod.POST, request, String.class);

        return getResponseEntityAsJsonElement(responseEntity);

    }

    public JsonElement put(String path, JsonObject body) {

        RestTemplate restTemplate = new RestTemplate();

        HttpHeaders headers = createHeaders(user, password);

        headers.setContentType(MediaType.APPLICATION_JSON);

        HttpEntity<String> request = new HttpEntity<>(body.toString(), headers);

        ResponseEntity<String> responseEntity = restTemplate.exchange(registryUrl + path, HttpMethod.PUT, request, String.class);

        return getResponseEntityAsJsonElement(responseEntity);

    }

    public JsonElement get(String path, Map<String, String> params) {

        RestTemplate restTemplate = new RestTemplate();

        String url = registryUrl + path + ((params != null) ? createParams(params) : null);

        ResponseEntity<String> responseEntity = restTemplate.exchange

                (url, HttpMethod.GET, new HttpEntity<>(createHeaders(user, password)), String.class);

        return getResponseEntityAsJsonElement(responseEntity);

    }

    public JsonElement delete(String path) {

        RestTemplate restTemplate = new RestTemplate();

        String url = registryUrl + path;

        ResponseEntity<String> responseEntity = restTemplate.exchange

                (url, HttpMethod.DELETE, new HttpEntity<>(createHeaders(user, password)), String.class);

        return getResponseEntityAsJsonElement(responseEntity);

    }

    private String createParams(Map<String, String> params) {

        StringBuilder ret = new StringBuilder("?");

        int count = 0;

        for (Map.Entry<String, String> param : params.entrySet()) {

            ret.append(param.getKey()).append("=").append(param.getValue());

            count++;

            if (count != params.entrySet().size()) {

                ret.append("&");

            }

        }

        return ret.toString();

    }

    private HttpHeaders createHeaders(String username, String password) {

        return new HttpHeaders() {{

            String auth = username + ":" + password;

            byte[] encodedAuth = Base64.encodeBase64(

                    auth.getBytes(Charset.forName("US-ASCII")));

            String authHeader = "Basic " + new String(encodedAuth);

            set("Authorization", authHeader);

        }};

    }

    private JsonElement getResponseEntityAsJsonElement(ResponseEntity<String> responseEntity) {

        if (responseEntity != null && responseEntity.getBody() != null) {

            logger.info(responseEntity.getBody());

            try {

                return new JsonParser().parse(responseEntity.getBody());

            } catch (Exception e) {

                logger.warn("Could not parse response body", e);

            }

        }

        return null;

    }

}