content: package com.alibaba.datax.plugin.writer.doriswriter;
  
  import com.alibaba.fastjson2.JSON;
  import org.apache.commons.codec.binary.Base64;
  import org.apache.http.HttpEntity;
  import org.apache.http.HttpHeaders;
  import org.apache.http.client.config.RequestConfig;
  import org.apache.http.client.methods.CloseableHttpResponse;
  import org.apache.http.client.methods.HttpGet;
  import org.apache.http.client.methods.HttpPut;
  import org.apache.http.entity.ByteArrayEntity;
  import org.apache.http.impl.client.CloseableHttpClient;
  import org.apache.http.impl.client.DefaultRedirectStrategy;
  import org.apache.http.impl.client.HttpClientBuilder;
  import org.apache.http.impl.client.HttpClients;
  import org.apache.http.util.EntityUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  import java.net.HttpURLConnection;
  import java.net.URL;
  import java.nio.ByteBuffer;
  import java.nio.charset.StandardCharsets;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.TimeUnit;
  import java.util.stream.Collectors;
  
  public class DorisStreamLoadObserver {
      private static final Logger LOG = LoggerFactory.getLogger(DorisStreamLoadObserver.class);
  
      private Keys options;
  
      private long pos;
      private static final String RESULT_FAILED = "Fail";
      private static final String RESULT_LABEL_EXISTED = "Label Already Exists";
      private static final String LAEBL_STATE_VISIBLE = "VISIBLE";
      private static final String LAEBL_STATE_COMMITTED = "COMMITTED";
      private static final String RESULT_LABEL_PREPARE = "PREPARE";
      private static final String RESULT_LABEL_ABORTED = "ABORTED";
      private static final String RESULT_LABEL_UNKNOWN = "UNKNOWN";
  
  
      public DorisStreamLoadObserver ( Keys options){
          this.options = options;
      }
  
      public void streamLoad(WriterTuple data) throws Exception {
          String host = getLoadHost();
          if(host == null){
              throw new IOException ("load_url cannot be empty, or the host cannot connect.Please check your configuration.");
          }
          String loadUrl = new StringBuilder(host)
                  .append("/api/")
                  .append(options.getDatabase())
                  .append("/")
                  .append(options.getTable())
                  .append("/_stream_load")
                  .toString();
          LOG.info("Start to join batch data: rows[{}] bytes[{}] label[{}].", data.getRows().size(), data.getBytes(), data.getLabel());
          Map<String, Object> loadResult = put(loadUrl, data.getLabel(), addRows(data.getRows(), data.getBytes().intValue()));
          LOG.info("StreamLoad response :{}",JSON.toJSONString(loadResult));
          final String keyStatus = "Status";
          if (null == loadResult || !loadResult.containsKey(keyStatus)) {
              throw new IOException("Unable to flush data to Doris: unknown result status.");
          }
          LOG.debug("StreamLoad response:{}",JSON.toJSONString(loadResult));
          if (RESULT_FAILED.equals(loadResult.get(keyStatus))) {
              throw new IOException(
                      new StringBuilder("Failed to flush data to Doris.\n").append(JSON.toJSONString(loadResult)).toString()
              );
          } else if (RESULT_LABEL_EXISTED.equals(loadResult.get(keyStatus))) {
              LOG.debug("StreamLoad response:{}",JSON.toJSONString(loadResult));
              checkStreamLoadState(host, data.getLabel());
          }
      }
  
      private void checkStreamLoadState(String host, String label) throws IOException {
          int idx = 0;
          while(true) {
              try {
                  TimeUnit.SECONDS.sleep(Math.min(++idx, 5));
              } catch (InterruptedException ex) {
                  break;
              }
              try (CloseableHttpClient httpclient = HttpClients.createDefault()) {
                  HttpGet httpGet = new HttpGet(new StringBuilder(host).append("/api/").append(options.getDatabase()).append("/get_load_state?label=").append(label).toString());
                  httpGet.setHeader("Authorization", getBasicAuthHeader(options.getUsername(), options.getPassword()));
                  httpGet.setHeader("Connection", "close");
  
                  try (CloseableHttpResponse resp = httpclient.execute(httpGet)) {
                      HttpEntity respEntity = getHttpEntity(resp);
                      if (respEntity == null) {
                          throw new IOException(String.format("Failed to flush data to Doris, Error " +
                                  "could not get the final state of label[%s].\n", label), null);
                      }
                      Map<String, Object> result = (Map<String, Object>)JSON.parse(EntityUtils.toString(respEntity));
                      String labelState = (String)result.get("data");
                      if (null == labelState) {
                          throw new IOException(String.format("Failed to flush data to Doris, Error " +
                                  "could not get the final state of label[%s]. response[%s]\n", label, EntityUtils.toString(respEntity)), null);
                      }
                      LOG.info(String.format("Checking label[%s] state[%s]\n", label, labelState));
                      switch(labelState) {
                          case LAEBL_STATE_VISIBLE:
                          case LAEBL_STATE_COMMITTED:
                              return;
                          case RESULT_LABEL_PREPARE:
                              continue;
                          case RESULT_LABEL_ABORTED:
                              throw new DorisWriterExcetion (String.format("Failed to flush data to Doris, Error " +
                                      "label[%s] state[%s]\n", label, labelState), null, true);
                          case RESULT_LABEL_UNKNOWN:
                          default:
                              throw new IOException(String.format("Failed to flush data to Doris, Error " +
                                      "label[%s] state[%s]\n", label, labelState), null);
                      }
                  }
              }
          }
      }
  
      private byte[] addRows(List<byte[]> rows, int totalBytes) {
          if (Keys.StreamLoadFormat.CSV.equals(options.getStreamLoadFormat())) {
              Map<String, Object> props = (options.getLoadProps() == null ? new HashMap<> () : options.getLoadProps());
              byte[] lineDelimiter = DelimiterParser.parse((String)props.get("line_delimiter"), "\n").getBytes(StandardCharsets.UTF_8);
              ByteBuffer bos = ByteBuffer.allocate(totalBytes + rows.size() * lineDelimiter.length);
              for (byte[] row : rows) {
                  bos.put(row);
                  bos.put(lineDelimiter);
              }
              return bos.array();
          }
  
          if (Keys.StreamLoadFormat.JSON.equals(options.getStreamLoadFormat())) {
              ByteBuffer bos = ByteBuffer.allocate(totalBytes + (rows.isEmpty() ? 2 : rows.size() + 1));
              bos.put("[".getBytes(StandardCharsets.UTF_8));
              byte[] jsonDelimiter = ",".getBytes(StandardCharsets.UTF_8);
              boolean isFirstElement = true;
              for (byte[] row : rows) {
                  if (!isFirstElement) {
                      bos.put(jsonDelimiter);
                  }
                  bos.put(row);
                  isFirstElement = false;
              }
              bos.put("]".getBytes(StandardCharsets.UTF_8));
              return bos.array();
          }
          throw new RuntimeException("Failed to join rows data, unsupported `format` from stream load properties:");
      }
      private Map<String, Object> put(String loadUrl, String label, byte[] data) throws IOException {
          LOG.info(String.format("Executing stream load to: '%s', size: '%s'", loadUrl, data.length));
          final HttpClientBuilder httpClientBuilder = HttpClients.custom()
                  .setRedirectStrategy(new DefaultRedirectStrategy () {
                      @Override
                      protected boolean isRedirectable(String method) {
                          return true;
                      }
                  });
          try ( CloseableHttpClient httpclient = httpClientBuilder.build()) {
              HttpPut httpPut = new HttpPut(loadUrl);
              httpPut.removeHeaders(HttpHeaders.CONTENT_LENGTH);
              httpPut.removeHeaders(HttpHeaders.TRANSFER_ENCODING);
              List<String> cols = options.getColumns();
              if (null != cols && !cols.isEmpty() && Keys.StreamLoadFormat.CSV.equals(options.getStreamLoadFormat())) {
                  httpPut.setHeader("columns", String.join(",", cols.stream().map(f -> String.format("`%s`", f)).collect(Collectors.toList())));
              }
              if (null != options.getLoadProps()) {
                  for (Map.Entry<String, Object> entry : options.getLoadProps().entrySet()) {
                      httpPut.setHeader(entry.getKey(), String.valueOf(entry.getValue()));
                  }
              }
              httpPut.setHeader("Expect", "100-continue");
              httpPut.setHeader("label", label);
              httpPut.setHeader("two_phase_commit", "false");
              httpPut.setHeader("Authorization", getBasicAuthHeader(options.getUsername(), options.getPassword()));
              httpPut.setEntity(new ByteArrayEntity(data));
              httpPut.setConfig(RequestConfig.custom().setRedirectsEnabled(true).build());
              try ( CloseableHttpResponse resp = httpclient.execute(httpPut)) {
                  HttpEntity respEntity = getHttpEntity(resp);
                  if (respEntity == null)
                      return null;
                  return (Map<String, Object>)JSON.parse(EntityUtils.toString(respEntity));
              }
          }
      }
  
      private String getBasicAuthHeader(String username, String password) {
          String auth = username + ":" + password;
          byte[] encodedAuth = Base64.encodeBase64(auth.getBytes(StandardCharsets.UTF_8));
          return new StringBuilder("Basic ").append(new String(encodedAuth)).toString();
      }
  
      private HttpEntity getHttpEntity(CloseableHttpResponse resp) {
          int code = resp.getStatusLine().getStatusCode();
          if (200 != code) {
              LOG.warn("Request failed with code:{}", code);
              return null;
          }
          HttpEntity respEntity = resp.getEntity();
          if (null == respEntity) {
              LOG.warn("Request failed with empty response.");
              return null;
          }
          return respEntity;
      }
  
      private String getLoadHost() {
          List<String> hostList = options.getLoadUrlList();
          Collections.shuffle(hostList);
          String host = new StringBuilder("http://").append(hostList.get((0))).toString();
          if (checkConnection(host)){
              return host;
          }
          return null;
      }
  
      private boolean checkConnection(String host) {
          try {
              URL url = new URL(host);
              HttpURLConnection co =  (HttpURLConnection) url.openConnection();
              co.setConnectTimeout(5000);
              co.connect();
              co.disconnect();
              return true;
          } catch (Exception e1) {
              e1.printStackTrace();
              return false;
          }
      }
  }
  